CMP Journal 2025-07-09
Statistics
Nature: 26
Nature Physics: 2
Physical Review Letters: 33
Physical Review X: 2
Review of Modern Physics: 1
arXiv: 71
Nature
Replay and representation dynamics in the hippocampus of freely flying bats
Original Paper | Learning and memory | 2025-07-08 20:00 EDT
Angelo Forli, Wudi Fan, Kevin K. Qi, Michael M. Yartsev
Cognitive functions for navigation and memory rely on emergent properties of neural ensembles in the hippocampus, such as activity replay1-5 and theta sequences6-9. Yet, whether and how these phenomena generalize across species with distinct navigational demands and neurophysiological properties remain unclear. Here, we wirelessly recorded neural activity from large populations of cells and local field potentials (LFPs) from the hippocampus of freely flying bats engaged in free, spontaneous foraging behavior. During rest, we identified time-compressed forward and reverse replay of multiple flight trajectories coinciding with sharp-wave ripples (SWRs). Yet, replays occurred predominantly at locations that were both spatially and temporally distant from the replayed behavior, and their speed scaled with trajectory length, challenging existing models of replay mechanisms. During flight, neural ensembles exhibited fast representational sweeps, where the decoded location cyclically moved ahead of the bat’s position. In contrast to reports in rodents, sweeps occurred in the absence of theta oscillations and were instead phase-locked to a prominent motor behavioral rhythm - the bat’s wingbeat cycle. This suggests that behaviorally-relevant sensorimotor rhythms can interact with hippocampal ensemble dynamics in a highly structured manner. Combined, our findings challenge existing models of ensemble dynamics in the mammalian hippocampus and highlight the importance of comparative studies under ethologically relevant conditions for elucidating brain function.
Learning and memory, Neural circuits
Feline infectious peritonitis epizootic caused by a recombinant coronavirus
Original Paper | Viral epidemiology | 2025-07-08 20:00 EDT
Charalampos Attipa, Amanda S. Warr, Demetris Epaminondas, Marie O’Shea, Andrew J. Hanton, Sarah Fletcher, Alexandra Malbon, Maria Lyraki, Rachael Hammond, Alexandros Hardas, Antria Zanti, Stavroula Loukaidou, Michaela Gentil, Danielle Gunn-Moore, Samantha J. Lycett, Stella Mazeri, Christine Tait-Burkard
Cross-species transmission of coronaviruses (CoVs) poses a serious threat to both animal and human health1-3. Whilst the large RNA genome of CoVs shows relatively low mutation rates, recombination within genera is frequently observed4-7. Companion animals are often overlooked in the transmission cycle of viral diseases; however, the close relationship of feline (FCoV) and canine CoV (CCoV) to human hCoV-229E5,8, as well as their susceptibility to SARS-CoV-29 highlight their importance in potential transmission cycles. Whilst recombination between CCoV and FCoV of a large fragment spanning orf1b to M has been previously described5,10, here we report the emergence of a novel, highly pathogenic FCoV-CCoV recombinant responsible for a rapidly spreading outbreak of feline infectious peritonitis (FIP), originating in Cyprus11. The minor recombinant region, spanning spike (S), shows 96.5% sequence identity to the pantropic canine coronavirus NA/09. Infection has rapidly spread, infecting cats of all ages. Development of FIP appears very frequent and sequence identities of samples from cats in different districts of the island is strongly supportive of direct transmission. A near cat-specific deletion in the domain 0 of S is present in >90% of FIP cats. It is unclear as yet whether this deletion is directly associated with disease development and may be linked to a biotype switch12. The domain 0 deletion and several amino acid changes in S, particularly the receptor binding domain, indicate potential changes to receptor binding and cell tropism.
Viral epidemiology, Viral transmission, Virus structures
A single-cell multi-omics atlas of rice
Original Paper | Computational biology and bioinformatics | 2025-07-08 20:00 EDT
Xiangyu Wang, Huanwei Huang, Sanjie Jiang, Jingmin Kang, Dongwei Li, Kailai Wang, Shang Xie, Cheng Tong, Chaofan Liu, Guihua Hu, Haoqian Li, Cong Li, Liwen Yang, Yike Ding, Shang-Tong Li, Faming Wang, Jan U. Lohmann, Zhe Liang, Xiaofeng Gu
Cell functions across eukaryotes are driven by specific gene expression programs, which are dependent on chromatin structure1,2,3. Here we report a single-cell multi-omics atlas of rice, one of the world’s major crops. By simultaneously profiling chromatin accessibility and RNA expression in 116,564 cells from eight organs, we identified cell-type-specific gene regulatory networks and described novel cell states, such as a ‘transitional state’ in floral meristems. On the basis of our network analyses, we uncovered the function of the cell-type-specific regulatory hubs RSR1, F3H and LTPL120 during rice development. Our analysis revealed correlations between cell type and agronomic traits, as well as conserved and divergent cell-type functions during evolution. In summary, this study not only offers a unique single-cell multi-omics resource for a major crop but also advances our understanding of cell-type functions and the underlying molecular programs in rice.
Computational biology and bioinformatics, Plant molecular biology, RNA sequencing
The spatiotemporal distribution of human pathogens in ancient Eurasia
Original Paper | Apoptosis | 2025-07-08 20:00 EDT
Martin Sikora, Elisabetta Canteri, Antonio Fernandez-Guerra, Nikolay Oskolkov, Rasmus Ågren, Lena Hansson, Evan K. Irving-Pease, Barbara Mühlemann, Sofie Holtsmark Nielsen, Gabriele Scorrano, Morten E. Allentoft, Frederik Valeur Seersholm, Hannes Schroeder, Charleen Gaunitz, Jesper Stenderup, Lasse Vinner, Terry C. Jones, Björn Nystedt, Karl-Göran Sjögren, Julian Parkhill, Lars Fugger, Fernando Racimo, Kristian Kristiansen, Astrid K. N. Iversen, Eske Willerslev
Infectious diseases have had devastating effects on human populations throughout history, but important questions about their origins and past dynamics remain1. To create an archaeogenetic-based spatiotemporal map of human pathogens, we screened shotgun-sequencing data from 1,313 ancient humans covering 37,000 years of Eurasian history. We demonstrate the widespread presence of ancient bacterial, viral and parasite DNA, identifying 5,486 individual hits against 492 species from 136 genera. Among those hits, 3,384 involve known human pathogens2, many of which had not previously been identified in ancient human remains. Grouping the ancient microbial species according to their likely reservoir and type of transmission, we find that most groups are identified throughout the entire sampling period. Zoonotic pathogens are only detected from around 6,500 years ago, peaking roughly 5,000 years ago, coinciding with the widespread domestication of livestock3. Our findings provide direct evidence that this lifestyle change resulted in an increased infectious disease burden. They also indicate that the spread of these pathogens increased substantially during subsequent millennia, coinciding with the pastoralist migrations from the Eurasian Steppe4,5.
Apoptosis, Biochemistry, Biological anthropology, Evolutionary genetics, Infectious diseases, Microbial genetics, Population genetics
How short peptides disassemble tau fibrils in Alzheimer’s disease
Original Paper | Alzheimer’s disease | 2025-07-08 20:00 EDT
Ke Hou, Peng Ge, Michael R. Sawaya, Liisa Lutter, Joshua L. Dolinsky, Yuan Yang, Yi Xiao Jiang, David R. Boyer, Xinyi Cheng, Justin Pi, Jeffrey Zhang, Jiahui Lu, Romany Abskharon, Shixin Yang, Zhiheng Yu, Juli Feigon, David S. Eisenberg
Reducing fibrous aggregates of the protein tau is a possible strategy for halting the progression of Alzheimer’s disease (AD)1. Previously, we found that in vitro, the d-enantiomeric peptide (D-peptide) D-TLKIVWC disassembles ultra-stable tau fibrils extracted from the autopsied brains of individuals with AD (hereafter, these tau fibrils are referred to as AD-tau) into benign segments, with no energy source other than ambient thermal agitation2. To consider D-peptide-mediated disassembly as a potential route to therapeutics for AD, it is essential to understand the mechanism and energy source of the disassembly action. Here, we show that the assembly of D-peptides into amyloid-like (‘mock-amyloid’) fibrils is essential for AD-tau disassembly. These mock-amyloid fibrils have a right-handed twist but are constrained to adopt a left-handed twist when templated in complex with AD-tau. The release of strain that accompanies the conversion of left-twisted to right-twisted, relaxed mock-amyloid produces a torque that is sufficient to break the local hydrogen bonding between tau molecules, and leads to the fragmentation of AD-tau. This strain-relief mechanism seems to operate in other examples of amyloid fibril disassembly, and could inform the development of first-in-class therapeutics for amyloid diseases.
Alzheimer’s disease, Cryoelectron microscopy
Decadal changes in atmospheric circulation detected in cloud motion vectors
Original Paper | Atmospheric dynamics | 2025-07-08 20:00 EDT
Larry Di Girolamo, Guangyu Zhao, Gan Zhang, Zhuo Wang, Jesse Loveridge, Arka Mitra
Changing atmospheric circulations shift global weather patterns and their extremes, profoundly affecting human societies and ecosystems. Studies using atmospheric reanalysis and climate model data1,2,3,4,5,6,7,8,9 indicate diverse circulation changes in recent decades but show discrepancies in magnitude and even direction, underscoring the urgent need for validation with independent, climate-quality measurements3. Here we show statistically significant changes in tropospheric circulation over the past two decades using satellite-observed, height-resolved cloud motion vectors from the Multi-angle Imaging SpectroRadiometer (MISR)10,11. Upper tropospheric cloud motion speeds in the mid-latitudes have increased by up to about 4 m s-1 decade-1. This acceleration is primarily because of the strengthening of meridional flow, potentially indicating more poleward storm tracks or intensified extratropical cyclones. The Northern and Southern Hemisphere tropics shifted poleward at rates of 0.42 ± 0.22 and 0.02 ± 0.14° latitude decade-1 (95% confidence interval), respectively, whereas the corresponding polar fronts shifted at rates of 0.37 ± 0.31 and 0.31 ± 0.21° latitude decade-1. We also show that the widely used ERA5 (ref. 12) reanalysis winds subsampled to the MISR are in good agreement with the climatological values and trends of the MISR but indicate probable ERA5 biases in the upper troposphere. These MISR-based observations provide critical benchmarks for refining reanalysis and climate models to advance our understanding of climate change impacts on cloud and atmospheric circulations.
Atmospheric dynamics, Climate-change impacts
A haplotype-resolved pangenome of the barley wild relative Hordeum bulbosum
Original Paper | Agricultural genetics | 2025-07-08 20:00 EDT
Jia-Wu Feng, Hélène Pidon, Maria Cuacos, Thomas Lux, Axel Himmelbach, Reza Haghi, Jörg Fuchs, Georg Haberer, Yi-Tzu Kuo, Yu Guo, Murukarthick Jayakodi, Helena Toegelová, Dörte Harpke, Manuela Knauft, Anne Fiebig, Maren Maruschewski, Moshe Ronen, Amir Sharon, Hana Šimková, Klaus F. X. Mayer, Manuel Spannagl, Jochen Kumlehn, Stefan Heckmann, Andreas Houben, Frank R. Blattner, Nils Stein, Martin Mascher
Wild plants can contribute valuable genes to their domesticated relatives1. Fertility barriers and a lack of genomic resources have hindered the effective use of crop-wild introgressions. Decades of research into barley’s closest wild relative, Hordeum bulbosum, a grass native to the Mediterranean basin and Western Asia, have yet to manifest themselves in the release of a cultivar bearing alien genes2. Here we construct a pangenome of bulbous barley comprising 10 phased genome sequence assemblies amounting to 32 distinct haplotypes. Autotetraploid cytotypes, among which the donors of resistance-conferring introgressions are found, arose at least twice, and are connected among each other and to diploid forms through gene flow. The differential amplification of transposable elements after barley and H. bulbosum diverged from each other is responsible for genome size differences between them. We illustrate the translational value of our resource by mapping non-host resistance to a viral pathogen to a structurally diverse multigene cluster that has been implicated in diverse immune responses in wheat and barley.
Agricultural genetics, Evolutionary genetics, Genomics, Plant evolution, Structural variation
Metalasers with arbitrarily shaped wavefront
Original Paper | Nanophotonics and plasmonics | 2025-07-08 20:00 EDT
Yixuan Zeng, Xinbo Sha, Chi Zhang, Yao Zhang, Huachun Deng, Haipeng Lu, Geyang Qu, Shumin Xiao, Shaohua Yu, Yuri Kivshar, Qinghai Song
Integrated nanolasers have been explored for decades owing to their important role in many applications, ranging from optical information processing and communications to medical treatments1,2,3,4,5,6. Although polarization, orbital angular momentum and directivity of nanolasers have been successfully manipulated7,8,9, neither their laser wavefront nor radiation characteristics can be customized at will. More optical elements are often required to further modify the laser characteristics, making the lasing system bulky and restricted by inevitable speckle noise. Here we suggest and realize a new type of laser, a metalaser, by using the interplay between local and nonlocal responses of dielectric resonant metasurfaces. The lasing mode is confined by nonlocal interaction between meta-atoms of a planar structure and the beam wavefront is precisely shaped by locally varying dipole momenta. Consequently, the metalaser emission can directly have any desired profile, including focal spots, focal lines, vector beams, vortex beams and even holograms. Notably, the scattered waves of the metalaser do not undergo resonant amplification like laser modes, being orders of magnitude weaker. As a consequence, the speckle noise becomes negligibly small in our metalaser holograms, providing a viable solution to the speckle noise problem of conventional laser holograms. This finding enriches our understanding of lasers and promotes their performance for various optical and photonic applications.
Nanophotonics and plasmonics, Solid-state lasers
Nutrients activate distinct patterns of small-intestinal enteric neurons
Original Paper | Neurophysiology | 2025-07-08 20:00 EDT
Candice Fung, Tom Venneman, Amy M. Holland, Tobie Martens, Milvia I. Alata, Marlene M. Hao, Ceyhun Alar, Yuuki Obata, Jan Tack, Alejandro Sifrim, Vassilis Pachnis, Werend Boesmans, Pieter Vanden Berghe
The ability to detect and respond appropriately to ingested nutrients is essential for an organism’s survival and to ensure its metabolic demands are met. Nutrient signals from the gut lumen trigger local intestinal reflexes in the enteric nervous system (ENS) to facilitate digestion and absorption1,2,3,4, but the precise cellular pathways that are involved in the initial neuronal sensory process remain unclear. The extent to which the ENS is capable of discerning different luminal chemicals is also unknown. Here we use calcium imaging to identify specific enteric pathways that are activated in response to luminal nutrients applied to mouse jejunum. Notably, we show that different nutrients activate neurochemically defined ensembles of myenteric and submucosal neurons. Furthermore, we find that enteric neurons are not directly sensitive to nutrients but detect different luminal chemicals through the epithelium, mainly via a serotonin signalling pathway. Finally, our data reveal a spatial distribution of luminal information along the radial axis of the intestine, whereby some signals that originate from the villus epithelium are transmitted first to the myenteric plexus, and then back to the submucosal plexus, which is closer to the lumen.
Neurophysiology, Peripheral nervous system
Bowhead whale faeces link increasing algal toxins in the Arctic to ocean warming
Original Paper | Climate-change ecology | 2025-07-08 20:00 EDT
Kathi A. Lefebvre, Patrick Charapata, Raphaela Stimmelmayr, Peigen Lin, Robert S. Pickart, Katherine A. Hubbard, Brian D. Bill, Gay Sheffield, Emily K. Bowers, Donald M. Anderson, Evangeline Fachon, Rick Thoman
Over the last two decades, ocean warming and rapid loss of sea ice have dramatically changed the Pacific Arctic marine environment1,2,3. These changes are predicted to increase harmful algal bloom prevalence and toxicity, as rising temperatures and larger open water areas are more favourable for growth of some toxic algal species4. It is well known that algal toxins are transferred through food webs during blooms and can have negative impacts on wildlife and human health5,6,7. Yet, there are no long-term quantitative reports on algal toxin presence in Arctic food webs to evaluate increasing exposure risks. In the present study, algal toxins were quantified in bowel samples collected from 205 bowhead whales harvested for subsistence purposes over 19 years. These filter-feeding whales served as integrated food web samplers for algal toxin presence in the Beaufort Sea as it relates to changing environmental conditions over two decades. Algal toxin prevalences and concentrations were significantly correlated with ocean heat flux, open water area, wind velocity and atmospheric pressure. These results provide confirmative oceanic, atmospheric and biological evidence for increasing algal toxin concentrations in Arctic food webs due to warming ocean conditions. This approach elucidates breakthrough mechanistic connections between warming oceans and increasing algal toxin exposure risks to Arctic wildlife, which threatens food security for Native Alaskan communities that have been reliant on marine resources for subsistence for 5,000 years (ref. 8).
Climate-change ecology, Marine biology, Marine mammals, Physical oceanography
Ultra-depleted mantle source of basalts from the South Pole-Aitken basin
Original Paper | Geochemistry | 2025-07-08 20:00 EDT
Qin Zhou, Wei Yang, Zhuyin Chu, Honggang Zhu, Saihong Yang, Xingguo Zeng, Ding-Shuai Xue, Li-Hui Jia, Guangliang Zhang, Hongbo Zhang, Yanhao Lin, Huijuan Zhang, Heng-Ci Tian, Peng Peng, Dan-Ping Zhang, Lixin Gu, Chunlai Li, Fu-Yuan Wu
Lunar mare basalts illuminate the nature of the Moon’s mantle, the lunar compositional asymmetry and the early lunar magma ocean (LMO)1,2,3. However, the characteristics of the mantle beneath the vast South Pole-Aitken (SPA) basin on the lunar farside remain a mystery. Here we present the petrology and geochemistry of basalt fragments from Chang’e-6 (CE6), the first returned lunar farside samples from the SPA basin4,5,6,7. These 2.8-billion-year-old CE6 basalts8 share similar major element compositions with the most evolved Apollo 12 ilmenite basalts. They exhibit extreme Sr-Nd depletion, with initial 87Sr/86Sr ratios of 0.699237 to 0.699329 and εNd(t) values (a measure of the neodymium isotopic composition) of 15.80 to 16.13. These characteristics indicate an ultra-depleted mantle, resulting from LMO crystallization and/or later depletion by melt extraction. The former scenario implies that the nearside and farside may possess an isotopically analogous depleted mantle endmember. The latter is probably related to the SPA impact, indicating that post-accretion massive impacts could have potentially triggered large-scale melt extraction of the underlying mantle. Either way, originating during the LMO or later melt extraction, the ultra-depleted mantle beneath the SPA basin offers a deep observational window into early lunar crust-mantle differentiation.
Geochemistry, Petrology
Loss of FCoV-23 spike domain 0 enhances fusogenicity and entry kinetics
Original Paper | Antibodies | 2025-07-08 20:00 EDT
M. Alejandra Tortorici, Annette Choi, Cecily A. Gibson, Jimin Lee, Jack T. Brown, Cameron Stewart, Anshu Joshi, Sheri Harari, Isabelle Willoughby, Catherine Treichel, Elizabeth M. Leaf, Jesse D. Bloom, Neil P. King, Christine Tait-Burkard, Gary R. Whittaker, David Veesler
The ability of coronaviruses to recombine and cross species barriers affects human and animal health globally and is a pandemic threat1,2. FCoV-23 is a recently emerged, highly pathogenic recombinant coronavirus responsible for a widespread outbreak of feline infectious peritonitis. Here we report cryogenic electron microscopy structures of two FCoV-23 spike isoforms that correspond to the in-host loss of domain 0 observed in clinical samples. The loss of domain 0 markedly enhances the fusogenicity and kinetics of entry into cells and possibly enables biotype switching and lethality. We show that FCoV-23 can use several aminopeptidase N orthologues as receptors and reveal the molecular determinants of receptor species tropism, including a glycan that modulates human receptor engagement. We define antigenic relationships among alphacoronaviruses that infect humans and other mammalian species and identify a cross-reactive alphacoronavirus monoclonal antibody that inhibits FCoV-23 entry. Our results pave the way for the development of vaccines and therapeutics that target this highly pathogenic virus.
Antibodies, Cryoelectron microscopy, Virus-host interactions
Selective remodelling of the adipose niche in obesity and weight loss
Original Paper | Cellular signalling networks | 2025-07-08 20:00 EDT
Antonio M. A. Miranda, Liam McAllan, Guianfranco Mazzei, Ivan Andrew, Iona Davies, Meryem Ertugrul, Julia Kenkre, Hiromi Kudo, Joana Carrelha, Bhavik Patel, Sophie Newton, Weihua Zhang, Alice Pollard, Amy Cross, Oliver McCallion, Mikyung Jang, Ka Lok Choi, Scarlett Brown, Yasmin Rasool, Marco Adamo, Mohamed Elkalaawy, Andrew Jenkinson, Borzoueh Mohammadi, Majid Hashemi, Robert Goldin, Laurence Game, Joanna Hester, Fadi Issa, Dylan G. Ryan, Patricia Ortega, Ahmed R. Ahmed, Rachel L. Batterham, John C. Chambers, Jaspal S. Kooner, Damir Baranasic, Michela Noseda, Tricia Tan, William R. Scott
Weight loss significantly improves metabolic and cardiovascular health in people with obesity1,2,3. The remodelling of adipose tissue (AT) is central to these varied and important clinical effects4. However, surprisingly little is known about the underlying mechanisms, presenting a barrier to treatment advances. Here we report a spatially resolved single-nucleus atlas (comprising 171,247 cells from 70 people) investigating the cell types, molecular events and regulatory factors that reshape human AT, and thus metabolic health, in obesity and therapeutic weight loss. We discover selective vulnerability to senescence in metabolic, precursor and vascular cells and reveal that senescence is potently reversed by weight loss. We define gene regulatory mechanisms and tissue signals that may drive a degenerative cycle of senescence, tissue injury and metabolic dysfunction. We find that weight loss reduces adipocyte hypertrophy and biomechanical constraint pathways, activating global metabolic flux and bioenergetic substrate cycles that may mediate systemic improvements in metabolic health. In the immune compartment, we demonstrate that weight loss represses obesity-induced macrophage infiltration but does not completely reverse activation, leaving these cells primed to trigger potential weight regain and worsen metabolic dysfunction. Throughout, we map cells to tissue niches to understand the collective determinants of tissue injury and recovery. Overall, our complementary single-nucleus and spatial datasets offer unprecedented insights into the basis of obese AT dysfunction and its reversal by weight loss and are a key resource for mechanistic and therapeutic exploration.
Cellular signalling networks, Gene regulatory networks, Metabolic syndrome, Obesity, RNA sequencing
Control of toxicity of fine particulate matter emissions in China
Original Paper | Environmental impact | 2025-07-08 20:00 EDT
Haotian Zheng, Di Wu, Shuxiao Wang, Xiangdong Li, Ling N. Jin, Bin Zhao, Shengyue Li, Yisheng Sun, Zhaoxin Dong, Qingru Wu, Xiu Chen, Yuzhe Liu, Jianmin Chen, Hezhong Tian, Qian Liu, Jingkun Jiang, Haidong Kan, Kebin He, Hong He, Chuncheng Chen, Jincai Zhao, Scott Weichenthal, John S. Ji, Aaron J. Cohen, Jiming Hao, Qing Li
Fine particulate matter (particulate matter with a diameter of 2.5 μm or less; PM2.5) causes millions of premature deaths globally1, but not all particles are equally harmful2,3,4. Current air-pollution control strategies, prioritizing PM2.5 mass reduction, have provided considerable health benefits but further refinements based on differences in the toxicity of various emission sources may provide greater benefits5,6,7. Here we integrated field measurements with air-quality modelling to assess the unequal toxicities of PM2.5 from various anthropogenic sources. Our findings revealed that the toxicity per unit of PM2.5 mass differed substantially between major sources, differing by up to two orders of magnitude. PM2.5 from solid fuel combustion in residential stoves had the highest toxicity, followed by those from the metallurgy industry, brake wear, diesel vehicles, petrol vehicles, the cement industry and power plants. We further analysed the source contributions of toxicity-adjusted PM2.5 emissions and population exposures in China. From 2005 to 2021, both the PM2.5 mass and relative-potency-adjusted emissions substantially decreased. Although industrial sources contributed 57.5% to the reduction in PM2.5 mass emissions, the reduction in relative potency-adjusted emissions was driven by residential combustion (approximately 80%). Clean-air policies should consider the differing toxicities of PM2.5 when formulating source-specific emission control regulations. This study proposes a cellular toxicity-based framework for PM2.5 reduction that could address the specific health risks in diverse regions, but further epidemiological studies will be required to confirm their relevance to human health outcomes and their application to public policy.
Environmental impact, Sustainability
The role of metabolism in shaping enzyme structures over 400 million years
Original Paper | Biochemistry | 2025-07-08 20:00 EDT
Oliver Lemke, Benjamin Murray Heineike, Sandra Viknander, Nir Cohen, Feiran Li, Jacob Lucas Steenwyk, Leonard Spranger, Federica Agostini, Cory Thomas Lee, Simran Kaur Aulakh, Judith Berman, Antonis Rokas, Jens Nielsen, Toni Ingolf Gossmann, Aleksej Zelezniak, Markus Ralser
Advances in deep learning and AlphaFold2 have enabled the large-scale prediction of protein structures across species, opening avenues for studying protein function and evolution1. Here we analyse 11,269 predicted and experimentally determined enzyme structures that catalyse 361 metabolic reactions across 225 pathways to investigate metabolic evolution over 400 million years in the Saccharomycotina subphylum2. By linking sequence divergence in structurally conserved regions to a variety of metabolic properties of the enzymes, we reveal that metabolism shapes structural evolution across multiple scales, from species-wide metabolic specialization to network organization and the molecular properties of the enzymes. Although positively selected residues are distributed across various structural elements, enzyme evolution is constrained by reaction mechanisms, interactions with metal ions and inhibitors, metabolic flux variability and biosynthetic cost. Our findings uncover hierarchical patterns of structural evolution, in which structural context dictates amino acid substitution rates, with surface residues evolving most rapidly and small-molecule-binding sites evolving under selective constraints without cost optimization. By integrating structural biology with evolutionary genomics, we establish a model in which enzyme evolution is intrinsically governed by catalytic function and shaped by metabolic niche, network architecture, cost and molecular interactions.
Biochemistry, Molecular evolution, Structural biology, Systems biology
Cryptic variation fuels plant phenotypic change through hierarchical epistasis
Original Paper | Epistasis | 2025-07-08 20:00 EDT
Sophia G. Zebell, Carlos Martí-Gómez, Blaine Fitzgerald, Camila P. Cunha, Michael Lach, Brooke M. Seman, Anat Hendelman, Simon Sretenovic, Yiping Qi, Madelaine Bartlett, Yuval Eshed, David M. McCandlish, Zachary B. Lippman
Cryptic genetic variants exert minimal phenotypic effects alone but are hypothesized to form a vast reservoir of genetic diversity driving trait evolvability through epistatic interactions1,2,3. This classical theory has been reinvigorated by pan-genomics, which is revealing pervasive variation within gene families, cis-regulatory regions and regulatory networks4,5,6. Testing the ability of cryptic variation to fuel phenotypic diversification has been hindered by intractable genetics, limited allelic diversity and inadequate phenotypic resolution. Here, guided by natural and engineered cis-regulatory cryptic variants in a paralogous gene pair, we identified additional redundant trans regulators, establishing a regulatory network controlling tomato inflorescence architecture. By combining coding mutations with cis-regulatory alleles in populations segregating for all four network genes, we generated 216 genotypes spanning a wide spectrum of inflorescence complexity and quantified branching in over 35,000 inflorescences. Analysis of this high-resolution genotype-phenotype map using a hierarchical model of epistasis revealed a layer of dose-dependent interactions within paralogue pairs enhancing branching, culminating in strong, synergistic effects. However, we also identified a layer of antagonism between paralogue pairs, whereby accumulating mutations in one pair progressively diminished the effects of mutations in the other. Our results demonstrate how gene regulatory network architecture and complex dosage effects from paralogue diversification converge to shape phenotypic space, producing the potential for both strongly buffered phenotypes and sudden bursts of phenotypic change.
Epistasis, Natural variation in plants, Plant genetics, Plant physiology, Quantitative trait
Phylogenetically informative proteins from an Early Miocene rhinocerotid
Original Paper | Palaeontology | 2025-07-08 20:00 EDT
Ryan S. Paterson, Meaghan Mackie, Alessio Capobianco, Nicola S. Heckeberg, Danielle Fraser, Beatrice Demarchi, Fazeelah Munir, Ioannis Patramanis, Jazmín Ramos-Madrigal, Shanlin Liu, Abigail D. Ramsøe, Marc R. Dickinson, Chloë Baldreki, Marisa Gilbert, Raffaele Sardella, Luca Bellucci, Gabriele Scorrano, Michela Leonardi, Andrea Manica, Fernando Racimo, Eske Willerslev, Kirsty E. H. Penkman, Jesper V. Olsen, Ross D. E. MacPhee, Natalia Rybczynski, Sebastian Höhna, Enrico Cappellini
In the past decade, ancient protein sequences have emerged as a valuable source of data for deep-time phylogenetic inference1,2,3,4. Still, even though ancient proteins have been reported from the Middle-Late Miocene5,6, the recovery of protein sequences providing subordinal-level phylogenetic insights does not exceed 3.7 million years ago (Pliocene)1. Here, we push this boundary back to 21-24 million years ago (Early Miocene) by retrieving enamel protein sequences of a rhinocerotid (Epiaceratherium sp.; CMNFV59632) from Canada’s High Arctic. We recover partial sequences of seven enamel proteins and more than 1,000 peptide-spectrum matches, spanning at least 251 amino acids. Endogeneity is in line with thermal age estimates and is supported by indicators of protein damage, including several spontaneous and irreversible chemical modifications accumulated during prolonged diagenesis. Bayesian tip-dating places the divergence time of CMNFV59632 in the Middle Eocene-Oligocene, coinciding with a phase of high rhinocerotid diversification7. This analysis identifies a later Oligocene divergence for Elasmotheriinae, weakening alternative models suggesting a deep basal split between Elasmotheriinae and Rhinocerotinae8,9. The findings are consistent with hypotheses on the origin of the enigmatic fauna of the Haughton Crater, which, in spite of considerable endemism, has similarity to distant Eurasian faunas10,11. Our findings demonstrate the potential of palaeoproteomics in obtaining phylogenetic information from a specimen that is approximately ten times older than any sample from which endogenous DNA has been obtained so far.
Palaeontology, Phylogenetics, Proteomics
Mapping the chemical complexity of plastics
Original Paper | Chemistry | 2025-07-08 20:00 EDT
L. Monclús, H. P. H. Arp, K. J. Groh, A. Faltynkova, M. E. Løseth, J. Muncke, Z. Wang, R. Wolf, L. Zimmermann, M. Wagner
Plastic pollution is a pervasive and growing global problem1,2,3,4. Chemicals in plastics are often not sufficiently considered in the overall strategy to prevent and mitigate the impacts of plastics on human health, the environment and circular economy5,6,7. Here we present an inventory of 16,325 known plastic chemicals with a focus on their properties, presence in plastic and hazards. We find that diverse chemical structures serve a small set of functions, including 5,776 additives, 3,498 processing aids, 1,975 starting substances and 1,788 non-intentionally added substances. Using a hazard-based approach, we identify more than 4,200 chemicals of concern, which are persistent, bioaccumulative, mobile or toxic. We also determine 15 priority groups of chemicals, for which more than 40% of their members are of concern. Finally, we examine data gaps regarding the basic properties, hazards, uses and exposure potential of plastic chemicals. Our work maps the chemical landscape of plastics and contributes to setting the baseline for a transition towards safer and more sustainable materials and products. We propose that removing known chemicals of concern, disclosing the chemical composition and simplifying the formulation of plastics can provide pathways towards this goal.
Chemistry, Environmental sciences, Materials science
Eighteen million years of diverse enamel proteomes from the East African Rift
Original Paper | Biogeochemistry | 2025-07-08 20:00 EDT
Daniel R. Green, Kevin T. Uno, Ellen R. Miller, Craig S. Feibel, Eipa Emmanuel Aoron, Catherine C. Beck, Aryeh Grossman, Francis M. Kirera, Martin M. Kirinya, Louise N. Leakey, Cynthia Liutkus-Pierce, Fredrick K. Manthi, Emmanuel K. Ndiema, Isaiah O. Nengo, Cyprian Nyete, John Rowan, Gabrielle A. Russo, William J. Sanders, Tara M. Smiley, Patricia Princehouse, Natasha S. Vitek, Timothy P. Cleland
Research into the palaeobiology of extinct taxa through ancient DNA and proteomics has been mostly limited to Plio-Pleistocene fossils1,2,3,4,5,6,7,8,9, due to molecular breakdown over time, which is exacerbated in tropical settings1,2,3. Here we sample small proteomes from the interior enamel of fossils at palaeontological sites from the Pleistocene to the Oligocene in the Turkana Basin, Kenya, which has produced a rich record of Cenozoic mammalian evolution10. Through a mass-spectrometry-based proteomic workflow, and using criteria to locate diagenetiforms derived from enamel, we recover fragments of enamelin, ameloblastin, matrix metalloprotease-20 and dentin matrix acidic phosphoprotein 1 from an Early Miocene rhinocerotid and several proboscideans collected from the sites of Buluk (16 million years ago; Ma) and Loperot (18 Ma). Diagenetiform counts decline in progressively older fossils, and we observe variability in Early Miocene preservation across sites. Phylogenetic analyses reveal the contribution of these sequences to the systematic placement of extinct taxa, although we caution that this approach must account for sparse fragments, uncertainty in fragment identification and possible sequence diagenesis. We identify likely modifications that support the ancient age of these proteins, and some of the oldest examples of advanced glycation end-products yet known. The discovery of protein sequences within dense enamel tissues in one of the persistently warmest regions on Earth promises the discovery of much older proteomes that will aid in the study of the palaeobiology and evolutionary relationships of extinct taxa.
Biogeochemistry, Palaeontology
Quantum correlations of spontaneous two-photon emission from a quantum dot
Original Paper | Quantum optics | 2025-07-08 20:00 EDT
Shunfa Liu, Yangpeng Wang, Yasser Saleem, Xueshi Li, Hanqing Liu, Cheng-Ao Yang, Jiawei Yang, Haiqiao Ni, Zhichuan Niu, Yun Meng, Xiaolong Hu, Ying Yu, Xuehua Wang, Moritz Cygorek, Jin Liu
Spontaneous two-photon emission (STPE) is a second-order quantum radiation process with implications in astrophysics1, atomic physics2 and quantum technology3. In particular, on-demand STPE from single quantum emitters has long been predicted to revolutionize photonic quantum science and technology4,5. Here we report STPE with brightness comparable to that of competing single-photon radiation from a single semiconductor quantum dot deterministically coupled to a high-quality micropillar cavity. This is because of strong vacuum fluctuations in the microcavity, which drive a biexciton directly to the ground state. We show the quantum nature associated with STPE in the cavity quantum electrodynamics regime using photon statistics measurements. Furthermore, STPE is exploited to build unconventional entangled quantum light sources that can simultaneously achieve near-unity entanglement fidelity for spontaneous parametric down-conversion sources and on-demand photon emission for atomic quantum emitters. Our work provides insights into the two-photon process in the quantum regime, which could empower photonic quantum technology with nonlinear quantum radiation.
Quantum optics, Single photons and quantum effects
Moiré materials based on M-point twisting
Original Paper | Ferromagnetism | 2025-07-08 20:00 EDT
Dumitru Călugăru, Yi Jiang, Haoyu Hu, Hanqi Pi, Jiabin Yu, Maia G. Vergniory, Jie Shan, Claudia Felser, Leslie M. Schoop, Dmitri K. Efetov, Kin Fai Mak, B. Andrei Bernevig
When two monolayer materials are stacked with a relative twist, an effective moiré translation symmetry emerges, leading to fundamentally different properties in the resulting heterostructure. As such, moiré materials have recently provided highly tunable platforms for exploring strongly correlated systems1,2. However, previous studies have focused almost exclusively on monolayers with triangular lattices and low-energy states near the Γ (refs. 3,4) or K (refs. 5,6,7,8,9) points of the Brillouin zone (BZ). Here we introduce a new class of moiré systems based on monolayers with triangular lattices but low-energy states at the M points of the BZ. These M-point moiré materials feature three time-reversal-preserving valleys related by threefold rotational symmetry. We propose twisted bilayers of exfoliable 1T-SnSe2 and 1T-ZrS2 as realizations of this new class. Using extensive ab initio simulations, we identify twist angles that yield flat conduction bands, provide accurate continuum models, analyse their topology and charge density and explore the platform’s rich physics. Notably, the M-point moiré Hamiltonians exhibit emergent momentum-space non-symmorphic symmetries and a kagome plane-wave lattice structure. This represents, to our knowledge, the first experimentally viable realization of projective representations of crystalline space groups in a non-magnetic system. With interactions, these systems act as six-flavour Hubbard simulators with Mott physics. Moreover, the presence of a momentum-space non-symmorphic in-plane mirror symmetry renders some of the M-point moiré Hamiltonians quasi-one-dimensional in each valley, suggesting the possibility of realizing Luttinger-liquid physics.
Ferromagnetism, Two-dimensional materials
Synthesis of deuterated acids and bases using bipolar membranes
Original Paper | Chemical engineering | 2025-07-08 20:00 EDT
Junying Yan, Chenxiao Jiang, Xiongzhi Zeng, Wanjie Song, Jie Yang, Xiaolin Ge, Liang Wu, Zhengjin Yang, Zhenyu Li, Yaoming Wang, Tongwen Xu
Deuterated acids/bases are high-value bulk chemicals used for synthesizing deuterated pharmaceuticals1,2, modifying optoelectronic materials3 and mediating hydrogen isotope exchange reactions4,5. However, conventional synthesis methods require harsh reaction conditions with high energy consumption6,7. Here we propose a versatile platform that takes advantage of heavy water dissociation in bipolar membranes (BPMs) to produce deuterated acids and bases under particularly mild conditions. Specifically, D2SO4 (2.75 mol l-1) and KOD (5.82 mol l-1), which are comparable with commercial products, were prepared using inexpensive D2O and K2SO4. We find that the deuteron generation rate is approximately 1.25 times greater than that of the protons, which is attributed to less co-ion leakage of D+ than H+ through the anion-exchange membrane (AEM), lower salt leakage within BPMs in D2O than in H2O and lower dehydration barrier of deuterons than proton clusters in the membrane phase. Compared with other contributing factors, salt leakage plays a relatively minor role in the observed H+/D+ concentration difference. This flexible and robust platform facilitates the synthesis of various deuterium-labelled compounds.
Chemical engineering, Process chemistry
Nanoplastic concentrations across the North Atlantic
Original Paper | Environmental chemistry | 2025-07-08 20:00 EDT
Sophie ten Hietbrink, Dušan Materić, Rupert Holzinger, Sjoerd Groeskamp, Helge Niemann
Plastic pollution of the marine realm is widespread, with most scientific attention given to macroplastics and microplastics1,2. By contrast, ocean nanoplastics (<1 μm) remain largely unquantified, leaving gaps in our understanding of the mass budget of this plastic size class3,4,5. Here we measure nanoplastic concentrations on an ocean-basin scale along a transect crossing the North Atlantic from the subtropical gyre to the northern European shelf. We find approximately 1.5-32.0 mg m-3 of polyethylene terephthalate (PET), polystyrene (PS) and polyvinyl chloride (PVC) nanoplastics throughout the entire water column. On average, we observe a 1.4-fold higher concentration of nanoplastics in the mixed layer when compared with intermediate water depth, with highest mixed-layer nanoplastic concentrations near the European continent. Nanoplastic concentrations at intermediate water depth are 1.8-fold higher in the subtropical gyre compared with the open North Atlantic outside the gyre. The lowest nanoplastic concentrations, with about 5.5 mg m-3 on average and predominantly composed of PET, are present in bottom waters. For the mixed layer of the temperate to subtropical North Atlantic, we estimate that the mass of nanoplastic may amount to 27 million tonnes (Mt). This is in the same range or exceeding previous budget estimates of macroplastics/microplastics for the entire Atlantic6,7 or the global ocean1,8. Our findings suggest that nanoplastics comprise the dominant fraction of marine plastic pollution.
Environmental chemistry, Ocean sciences
Coenzyme Q headgroup intermediates can ameliorate a mitochondrial encephalopathy
Original Paper | Developmental neurogenesis | 2025-07-08 20:00 EDT
Guangbin Shi, Claire Miller, Sota Kuno, Alejandro G. Rey Hipolito, Salsabiel El Nagar, Giulietta M. Riboldi, Megan Korn, Wyatt C. Tran, Zixuan Wang, Lia Ficaro, Tao Lin, Quentin Spillier, Begoña Gamallo-Lana, Drew R. Jones, Matija Snuderl, Soomin C. Song, Adam C. Mar, Alexandra L. Joyner, Roy V. Sillitoe, Robert S. Banh, Michael E. Pacold
Decreased brain levels of coenzyme Q10 (CoQ10), an endogenously synthesized lipophilic antioxidant1,2, underpin encephalopathy in primary CoQ10 deficiencies3,4 and are associated with common neurodegenerative diseases and the ageing process5,6. CoQ10 supplementation does not increase CoQ10 pools in the brain or in other tissues. The recent discovery of the mammalian CoQ10 headgroup synthesis pathway, in which 4-hydroxyphenylpyruvate dioxygenase-like protein (HPDL) makes 4-hydroxymandelate (4-HMA) to synthesize the CoQ10 headgroup precursor 4-hydroxybenzoate (4-HB)7, offers an opportunity to pharmacologically restore CoQ10 synthesis and mechanistically treat CoQ10 deficiencies. To test whether 4-HMA or 4-HB supplementation promotes CoQ10 headgroup synthesis in vivo, here we administered 4-HMA and 4-HB to Hpdl-/- mice, which model an ultra-rare, lethal mitochondrial encephalopathy in humans. Both 4-HMA and 4-HB were incorporated into CoQ9 and CoQ10 in the brains of Hpdl-/- mice. Oral treatment of Hpdl-/- pups with 4-HMA or 4-HB enabled 90-100% of Hpdl-/- mice to live to adulthood. Furthermore, 4-HB treatment stabilized and improved the neurological symptoms of a patient with progressive spasticity due to biallelic HPDL variants. Our work shows that 4-HMA and 4-HB can modify the course of mitochondrial encephalopathy driven by HPDL variants and demonstrates that CoQ10 headgroup intermediates can restore CoQ10 synthesis in vivo.
Developmental neurogenesis, Energy metabolism, Metabolomics
Single nuclear spin detection and control in a van der Waals material
Original Paper | Quantum metrology | 2025-07-08 20:00 EDT
Xingyu Gao, Sumukh Vaidya, Kejun Li, Zhun Ge, Saakshi Dikshit, Shimin Zhang, Peng Ju, Kunhong Shen, Yuanbin Jin, Yuan Ping, Tongcang Li
Optically active spin defects in solids1,2 are leading candidates for quantum sensing3,4 and quantum networking5,6. Recently, single spin defects were discovered in hexagonal boron nitride (hBN)7,8,9,10,11, a layered van der Waals (vdW) material. Owing to its two-dimensional structure, hBN allows spin defects to be positioned closer to target samples than in three-dimensional crystals, making it ideal for atomic-scale quantum sensing12, including nuclear magnetic resonance (NMR) of single molecules. However, the chemical structures of these defects7,8,9,10,11 remain unknown and detecting a single nuclear spin with a hBN spin defect has been elusive. Here we report the creation of single spin defects in hBN using 13C ion implantation and the identification of three distinct defect types based on hyperfine interactions. We observed both S = 1/2 and S = 1 spin states within a single hBN spin defect. We demonstrated atomic-scale NMR and coherent control of individual nuclear spins in a vdW material, with a π-gate fidelity up to 99.75% at room temperature. By comparing experimental results with density functional theory (DFT) calculations, we propose chemical structures for these spin defects. Our work advances the understanding of single spin defects in hBN and provides a pathway to enhance quantum sensing using hBN spin defects with nuclear spins as quantum memories.
Quantum metrology, Single photons and quantum effects, Two-dimensional materials
Reorganization of the theropod wrist preceded the origin of avian flight
Original Paper | Evolution | 2025-07-08 20:00 EDT
James G. Napoli, Matteo Fabbri, Alexander A. Ruebenstahl, Jingmai K. O’Connor, Bhart-Anjan S. Bhullar, Mark A. Norell
The carpus (wrist) of birds has a complex evolutionary history, long known to involve carpal reduction and recently shown to include topological replacement of one carpal (the ulnare) by another (the pisiform)1. The pisiform plays a crucial role in stabilization of the distal wingtip during flight2, and facilitates kinematic integration that ‘automates’ wing motion3. The apparent absence of a pisiform in all but the earliest theropod dinosaurs led to the proposal that it was lost early in theropod evolution and regained only in birds as a key step in the origin of flight1. Here, we describe the forelimb skeletons of two newly prepared theropod dinosaur specimens from the Gobi Desert of Mongolia, each of which preserves a pisiform, establishing its presence in Oviraptorosauria and Troodontidae in addition to birds. Reinterpretation of published material in light of these specimens shows a pisiform in a wide range of theropod species, including Microraptor4, Ambopteryx5 and Anchiornis6. Our results indicate that the pisiform replaced the ulnare by origin of the clade Pennaraptora, phylogenetically coincident with the hypothesized origin(s) of flight in birds and their closest relatives7,8. Taken together, our results indicate that replacement of the ulnare by the pisiform was a terminal step in assembly of the dinosaurian flight apparatus that occurred close to the origins of flight in theropod dinosaurs, rather than a novelty restricted to birds.
Evolution, Evolutionary developmental biology, Palaeontology, Zoology
Nature Physics
Nanophotonic quantum skyrmions enabled by semiconductor cavity quantum electrodynamics
Original Paper | Quantum information | 2025-07-08 20:00 EDT
Jiantao Ma, Jiawei Yang, Shunfa Liu, Bo Chen, Xueshi Li, Changkun Song, Guixin Qiu, Kai Zou, Xiaolong Hu, Feng Li, Ying Yu, Jin Liu
Skyrmions are topologically stable quasiparticles that have been investigated in contexts including particle physics, quantum field theory, acoustics and condensed-matter physics. Quantum optical skyrmions with local topological textures are expected to reshape the landscape of quantum photonic technology, although their experimental implementation has not yet been demonstrated. Here we present experimental realizations of nanophotonic quantum skyrmions using a semiconductor cavity quantum electrodynamics system. By manipulating the photonic spin-orbit coupling in a Gaussian microcavity, we obtained a confined optical mode whose polarizations feature skyrmionic topologies. With pronounced cavity quantum electrodynamics effects, we generated and detected single-photon skyrmions from a solid-state quantum emitter deterministically coupled to the Gaussian microcavity. The polarity associated with single-photon skyrmions can be swapped by flipping the polarization of the quantum emitter through the Zeeman effect. We also investigated the topological protection of quantum optical skyrmions under different perturbations. Our work opens an unexplored aspect of quantum light-matter interactions in the nanoscale and might advance resilient photonic quantum technology with high-dimensional qubits and high-capacity quantum memories.
Quantum information, Quantum optics, Single photons and quantum effects
Quantum thermalization and Floquet engineering in a spin ensemble with a clock transition
Original Paper | Quantum information | 2025-07-08 20:00 EDT
Mi Lei, Rikuto Fukumori, Chun-Ju Wu, Edwin Barnes, Sophia E. Economou, Joonhee Choi, Andrei Faraon
Platforms that enable the study and control of quantum many-body interactions are fundamentally important in quantum science and related emerging technologies. Optically addressable solid-state spins offer scalability to a large Hilbert space but suffer from large on-site disorder and undesired couplings to the environment. Here we investigated a strongly interacting ensemble of millions of optically addressable ytterbium-171 ions in a crystal. This platform features a clock transition that is first-order insensitive to magnetic fluctuations, thus exhibiting superior coherence and small disorder. Notably, the clock transition also gives rise to pure spin-exchange interactions, realizing the dipolar XY model, which is difficult to access in other solid-state spin systems. We exploited this feature to investigate quantum thermalization by varying the relative ratio of interaction strength to disorder, dynamically engineering the XY model into other many-body Hamiltonian models and realizing a time-crystalline phase of matter through periodic driving. Our results demonstrated that an ensemble of rare earth ions serves as a versatile test bed for many-body physics and developing quantum technologies.
Quantum information, Quantum simulation
Physical Review Letters
Quantum Thermal Analogs of Electric Circuits: A Universal Approach
Research article | Nonequilibrium & irreversible thermodynamics | 2025-07-08 06:00 EDT
Devvrat Tiwari, Samyadeb Bhattacharya, and Subhashish Banerjee
In this Letter, we develop a panoramic schematic of quantum thermal analogs of electric circuits in the steady state regime. We establish the foundations of said premise by defining the analogs of Kirchhoff’s laws for heat currents and temperature gradients, as well as a quantum thermal step transformer. Using this, we develop two novel quantum thermal circuits, viz., quantum thermal super Wheatstone bridge and quantum thermal adder circuit, paving the way for the corresponding integrated circuits. We further show that our approach encompasses various circuits like thermal diode, transistor, and Wheatstone bridge. This sheds new light on the present architecture of quantum device engineering.
Phys. Rev. Lett. 135, 020404 (2025)
Nonequilibrium & irreversible thermodynamics, Open quantum systems, Quantum circuits, Quantum thermodynamics, Thermoelectrics, Master equation
Self-Discharging Mitigated Quantum Battery
Research article | Open quantum systems & decoherence | 2025-07-08 06:00 EDT
Wan-Lu Song, Ji-Ling Wang, Bin Zhou, Wan-Li Yang, and Jun-Hong An
As a quantum thermodynamic device that utilizes quantum systems for energy storage and delivery, the quantum battery (QB) is expected to offer revolutionary advantages in terms of increasing the charging power and the extractable work by using quantum resources. However, the ubiquitous decoherence in the microscopic world inevitably forces the QB to spontaneously lose its stored energy. This is called the self-discharging of the QB and severely limits its realization. We propose a QB scheme based on the nitrogen-vacancy center in diamond, where the electronic spin serves as the QB. Inspired by our finding that the coherent ergotropy decays more slowly than the incoherent ergotropy, we reveal a mechanism to enhance the inherent robustness of the QB to the self-discharging by improving the ratio of coherent ergotropy to total ergotropy. The unique hyperfine interaction between the electron and the native $^{14}\mathrm{N}$ nucleus in our scheme allows one to coherently optimize this ratio. Mitigating the self-discharging and optimizing the extractable work simultaneously, our results pave the way for the practical realization of the QB.
Phys. Rev. Lett. 135, 020405 (2025)
Open quantum systems & decoherence, Quantum coherence & coherence measures, Quantum control, Quantum engineering
Exceptional Stationary State in a Dephasing Many-Body Open Quantum System
Research article | Open quantum systems & decoherence | 2025-07-08 06:00 EDT
Alice Marché, Gianluca Morettini, Leonardo Mazza, Lorenzo Gotta, and Luca Capizzi
We study a dephasing many-body open quantum system that hosts, together with the infinite-temperature state, another additional stationary state, that is associated with a nonextensive strong symmetry. This state, that is a pure dark state, is exceptional in that it retains memory of the initial condition, whereas any orthogonal state evolves toward the infinite-temperature state erasing any information on the initial state. We discuss the approach to stationarity of the model focusing in particular on the fate of interfaces between the two states. A simple model based on a membrane picture helps developing an effective large-scale theory, which is different from the usual hydrodynamics since no extensive conserved quantities are present. The fact that the model reaches stationary properties on timescales that diverge with the system size, while the Lindbladian gap is finite, is duly highlighted. We point out the reasons for considering these exceptional stationary states as quantum many-body scars in the open system framework.
Phys. Rev. Lett. 135, 020406 (2025)
Open quantum systems & decoherence, Quantum correlations in quantum information, Quantum-to-classical transition
Dark Spin-Cat States as Biased Qubits
Research article | Quantum error correction | 2025-07-08 06:00 EDT
Andreas Kruckenhauser, Ming Yuan, Han Zheng, Mikhail Mamaev, Pei Zeng, Xuanhui Mao, Qian Xu, Torsten V. Zache, Liang Jiang, Rick van Bijnen, and Peter Zoller
We present a biased atomic qubit, universally implementable across all atomic platforms, encoded as a ‘’spin cat’’ within ground state Zeeman levels. The key characteristic of our configuration is the coupling of the ground state spin manifold of size ${F}{g}\gg 1$ to an excited Zeeman spin manifold of size ${F}{e}={F}{g}- 1$ using light. This coupling results in eigenstates of the driven atom that include exactly two dark states in the ground state manifold, which are decoupled from light and immune to spontaneous emission from the excited states. These dark states constitute the spin cat, leading to the designation ‘’dark spin cat.’’ We demonstrate that under strong Rabi drive and for large ${F}{g}$, the dark spin cat is autonomously stabilized against common noise sources and encodes a qubit with significantly biased noise. Specifically, the bit-flip error rate decreases exponentially with ${F}_{g}$ relative to the dephasing rate. We provide an analysis of dark spin cats and their robustness to noise, and we discuss bias-preserving single qubit and entangling gates, exemplified on a Rydberg tweezer platform.
Phys. Rev. Lett. 135, 020601 (2025)
Quantum error correction, Quantum gates, Quantum information with atoms & light, Qubits
One-Shot Min-Entropy Calculation of Classical-Quantum States and Its Application to Quantum Cryptography
Entropy | 2025-07-08 06:00 EDT
Rong Wang and H. F. Chau
In quantum Shannon theory, various kinds of quantum entropies are used to characterize the capacities of noisy physical systems. Among them, min-entropy and its smooth version attract wide interest especially in the field of quantum cryptography as they can be used to bound the information obtained by an adversary. However, calculating the exact value or nontrivial bounds of min-entropy are extremely difficult because the composite system dimension may scale exponentially with the dimension of its subsystem. Here, we develop a one-shot lower bound calculation technique for the min-entropy of a classical-quantum state that is applicable to both finite and infinite dimensional reduced quantum states. Moreover, we show our technique is of practical interest in at least three situations. First, it offers an alternative tight finite-data analysis for the BB84 quantum key distribution scheme. Second, it gives the best finite-key bound known to date for a variant of device independent quantum key distribution protocol. Third, it provides a security proof for a novel source-independent continuous-variable quantum random number generation protocol. These results show the effectiveness and wide applicability of our approach.
Phys. Rev. Lett. 135, 020801 (2025)
Entropy, Quantum communication, protocols & technology, Quantum cryptography
Chip-to-Chip Quantum Photonic Controlled-not Gate Teleportation
Research article | Integrated optics | 2025-07-08 06:00 EDT
Lan-Tian Feng, Ming Zhang, Di Liu, Yu-Jie Cheng, Xin-Yu Song, Yu-Yang Ding, Dao-Xin Dai, Guo-Ping Guo, Guang-Can Guo, and Xi-Feng Ren
Quantum networks provide a novel framework for quantum information processing, significantly improving system capacity through the interconnection of modular quantum nodes. Beyond the capability to distribute quantum states, the ability to remotely control quantum gates is a pivotal step for quantum networks. Here, we implement high-fidelity quantum controlled-not (cnot) gate teleportation with high-dimensional path encoded silicon photonic integrated circuits. Based on on-chip generation of the path-entangled quantum state, cnot gate operation, and chip-to-chip quantum photonic interconnect, the cnot gate is teleported between two remote quantum nodes connected by the single-mode optical fiber. Equip with 5 m (1 km)-long interconnecting fiber, quantum gate teleportation is verified by entangling remote qubits with $95.69%\pm{}1.19%$ ($94.07%\pm{}1.54%$) average fidelity and gate tomography with $94.81%\pm{}0.81%$ ($93.04%\pm{}1.09%$) fidelity. These results advance the realization of large-scale and practical quantum networks with photonic integrated circuits.
Phys. Rev. Lett. 135, 020802 (2025)
Integrated optics, Optical quantum information processing, Quantum interconnects, Quantum networks
Precision Spectral Measurements of Chromium and Titanium from 10 to $250\text{ }\text{ }\mathrm{GeV}/n$ and Sub-Iron to Iron Ratio with the Calorimetric Electron Telescope on the International Space Station
Research article | Cosmic ray acceleration | 2025-07-08 06:00 EDT
O. Adriani et al. (CALET Collaboration)
The Calorimetric Electron Telescope (CALET), in operation on the International Space Station since 2015, collected a large sample of cosmic-ray (CR) iron and sub-iron events over a wide energy interval. In this Letter, we report an update of our previous measurement of the iron flux and we present—for the first time—a high statistics measurement of the spectra of two sub-iron elements Cr and Ti in the energy interval from 10 to $250\text{ }\text{ }\mathrm{GeV}/n$. The analyses are based on 8 years of data. Differently from older generations of cosmic-ray instruments which, in most cases, could not resolve individual sub-iron elements, CALET can identify each nuclear species from proton to nickel (and beyond) with a measurement of their electric charge. Thanks to the improvement in statistics and a more refined assessment of systematic uncertainties, the iron spectral shape is better resolved, at high energy, than in our previous paper, and we report its flux ratio to chromium and titanium. The measured fluxes of Cr and Ti show energy dependences compatible with a single power law with spectral indices $- 2.74\pm{}0.06$ and $- 2.88\pm{}0.06$, respectively.
Phys. Rev. Lett. 135, 021002 (2025)
Cosmic ray acceleration, Cosmic ray composition & spectra, Cosmic ray propagation, Cosmic rays & astroparticles
Computation of the Semiclassical Outflux Emerging from a Collapsing Spherical Null Shell
Research article | Quantum aspects of black holes | 2025-07-08 06:00 EDT
Amos Ori and Noa Zilberman
We consider a minimally coupled, massless quantum scalar field $\stackrel{^}{\mathrm{\Phi }}$ propagating in the background geometry of a four-dimensional black hole formed by the collapse of a spherical thin null shell, with a Minkowski interior and a Schwarzschild exterior. The field is taken in the natural ‘’in’’ vacuum state, namely, the quantum state in which no excitations arrive from past null infinity. Within the semiclassical framework, we analyze the vacuum polarization ${\langle{\stackrel{^}{\mathrm{\Phi }}}^{2}\rangle}{\mathrm{ren}}$ and the energy outflux density ${\langle{\stackrel{^}{T}}{uu}\rangle}{\mathrm{ren}}$ (where $u$ is the standard null Eddington coordinate) just outside the shell. Using the point-splitting method, we derive closed-form analytical expressions for both of these semiclassical quantities. In particular, our result for ${\langle{\stackrel{^}{T}}{uu}\rangle}{\mathrm{ren}}$ reveals that it vanishes like $(1- 2{M}{0}/{r}{0}{)}^{2}$ as the shell collapses toward the event horizon, where ${M}{0}$ is the shell’s mass and ${r}_{0}$ is the value of the area coordinate $r$ at the evaluation point. This confirms that, along a late-time outgoing null geodesic (i.e., one that emerges from the shell very close to the event horizon and propagates toward future null infinity), the outflux gradually evolves (from virtually zero) up to its final Hawking-radiation value while the geodesic traverses the strong-field region (rather than the Hawking-radiation outflux being emitted entirely from the collapsing shell, which would lead to significant backreaction effects).
Phys. Rev. Lett. 135, 021401 (2025)
Quantum aspects of black holes, Quantum fields in curved spacetime
Revisiting Scattering Enhancement from the Aharonov-Bohm Effect
Cosmic strings & domain walls | 2025-07-08 06:00 EDT
T. Daniel Brennan, Jaipratap Singh Grewal, and Eric Y. Yang
We revisit the problem of a charged particle scattering off of an Aharonov-Bohm cosmic string. A classic computation gave an infinite total scattering cross section, leading to a Callan-Rubakov-like enhancement which can have important implications on baryon number asymmetry in the early Universe. However, unlike the Callan-Rubakov effect, the Aharonov-Bohm interaction is topological and thus it is surprising that it leads to such a dramatic dynamical effect for single particle scattering. We reexamine this old problem through the modern lens of generalized global symmetries by embedding Aharanov-Bohm strings in a discrete gauge theory. We show that the scattering cross section is suppressed by the core size and there is thus no Callan-Rubakov-like enhancement.
Phys. Rev. Lett. 135, 021601 (2025)
Cosmic strings & domain walls, Dirac equation, Grand unified models, Topological field theories, Vortices in field theory
Minimal Model Renormalization Group Flows: Noninvertible Symmetries and Nonperturbative Description
Research article | Anomalies | 2025-07-08 06:00 EDT
Federico Ambrosino and Stefano Negro
In this Letter we continue the investigation of RG flows between Virasoro minimal models of two-dimensional conformal field theories that are protected by noninvertible symmetries. RG flows leaving unbroken a subcategory of noninvertible symmetries are associated with anomaly matching conditions that we employ systematically to map the space of flows between minimal models beyond the ${\mathbb{Z}}{2}$-symmetric proposed recently in the literature. We introduce a family of nonlinear integral equations that appear to encode the exact finite-size, ground-state energies of these flows, including nonintegrable cases, such as the recently proposed $\mathcal{M}(kq+I,q)\rightarrow \mathcal{M}(kq- I,q)$. Our family of NLIEs encompasses and generalizes the integrable flows known in the literature: ${\phi }{(1,3)}$, ${\phi }{(1,5)}$, ${\phi }{(1,2)}$ and ${\phi }_{(2,1)}$. This work uncovers a new interplay between exact solvability and noninvertible symmetries. Furthermore, our nonperturbative description provides a nontrivial test for all the flows conjectured by anomaly matching conditions, but so far not observed by other means.
Phys. Rev. Lett. 135, 021602 (2025)
Anomalies, Conformal field theory, Lower-dimensional field theories, Nonperturbative effects in field theory, Renormalization group
Evidence for ${B}^{- }\rightarrow {D}^{\ast\ast0}{\tau }^{- }\overline{ {\nu }_{\tau }}$ Decays
Research article | Electroweak interaction | 2025-07-08 06:00 EDT
R. Aaij et al. (LHCb Collaboration)
The first evidence for the decay ${B}^{- }\rightarrow {D}^{\ast\ast0}{\tau }^{- }{\overline{\nu }}{\tau }$ is obtained using proton-proton collision data collected by the LHCb experiment, corresponding to an integrated luminosity of $9\text{ }\text{ }{\mathrm{fb}}^{- 1}$, at centre-of-mass energies of 7, 8, and 13 TeV. Here, the ${D}^{\ast\ast0}$ meson represents any of the three excited charm mesons ${D}{1}(2420{)}^{0}$, ${D}{2}^{\ast}(2460{)}^{0}$, and ${D}{1}^{‘ }(2400{)}^{0}$. The ${B}^{- }\rightarrow {D}^{\ast\ast0}{\tau }^{- }{\overline{\nu }}{\tau }$ signal is measured with a significance of $3.5\sigma $, including systematic uncertainties. The combined branching fraction $\mathcal{B}({B}^{- }\rightarrow {D}{1,2}^{\ast\ast0}{\tau }^{- }{\overline{\nu }}{\tau })\times{}\mathcal{B}({D}{1,2}^{\ast\ast0}\rightarrow {D}^{\ast+}{\pi }^{- })$, where ${D}{1,2}^{\ast\ast0}$ denotes both ${D}{1}(2420{)}^{0}$ and ${D}{2}^{\ast}(2460{)}^{0}$ contributions, is measured to be $[0.051\pm{}0.013(\mathrm{stat})\pm{}0.006(\mathrm{syst})\pm{}0.009(\mathrm{ext})]%$, where the last uncertainty reflects that of the branching fraction of the normalization channel ${B}^{- }\rightarrow {D}{1,2}^{\ast\ast0}{ {D}{s}^{- }}^{(\ast)}$. The ratio between the tauonic and muonic semileptonic $B$ decays, with the latter taken from world average values, is also determined and found to be $\mathcal{R}({D}{1,2}^{\ast\ast0})=0.13\pm{}0.03(\mathrm{stat})\pm{}0.01(\mathrm{syst})\pm{}0.02(\mathrm{ext})$.
Phys. Rev. Lett. 135, 021802 (2025)
Electroweak interaction, Extensions of fermion sector, Extensions of scalar sector, Leptonic, semileptonic & radiative decays, Bottom mesons, Charmed mesons, Hadron colliders
Isolating Unisolated Upsilons with Anomaly Detection in CMS Open Data
Research article | Particle detection signatures | 2025-07-08 06:00 EDT
Rikab Gambhir, Radha Mastandrea, Benjamin Nachman, and Jesse Thaler
We present the first study of anti-isolated Upsilon decays to two muons ($\mathrm{\Upsilon }\rightarrow {\mu }^{+}{\mu }^{- }$) in proton-proton collisions at the Large Hadron Collider. Using a machine learning (ML)-based anomaly detection strategy, we ‘’rediscover’’ the $\mathrm{\Upsilon }$ in 13 TeV CMS Open Data from 2016, despite overwhelming anti-isolated backgrounds. We elevate the signal significance to $6.4\sigma $ using these methods, starting from $1.6\sigma $ using the dimuon mass spectrum alone. Moreover, we demonstrate improved sensitivity from using an ML-based estimate of the multifeature likelihood compared to traditional ‘’cut-and-count’’ methods. This is the first ever detection of anti-isolated Upsilons, which can be useful in the study of heavy-flavor fragmentation in quantum chromodynamics. Our Letter demonstrates that it is possible and practical to find real signals in experimental collider data using ML-based anomaly detection, and we distill a readily accessible benchmark dataset from the CMS Open Data to facilitate future anomaly detection developments.
Phys. Rev. Lett. 135, 021902 (2025)
Particle detection signatures, Phenomenology, Mesons, Muons, Machine learning
Neural-Network Extraction of Unpolarized Transverse-Momentum-Dependent Distributions
Research article | QCD phenomenology | 2025-07-08 06:00 EDT
Alessandro Bacchetta, Valerio Bertone, Chiara Bissolotti, Matteo Cerutti, Marco Radici, Simone Rodini, and Lorenzo Rossi (MAP (Multi-dimensional Analyses of Partonic distributions) Collaboration)
We present the first extraction of transverse-momentum-dependent distributions of unpolarized quarks from experimental Drell-Yan data using neural networks to parametrize their nonperturbative part. We show that neural networks outperform traditional parametrizations providing a more accurate description of data. This Letter establishes the feasibility of using neural networks to explore the multidimensional partonic structure of hadrons and paves the way for more accurate determinations based on machine-learning techniques.
Phys. Rev. Lett. 135, 021904 (2025)
QCD phenomenology, Quantum chromodynamics, Strong interaction, Transverse momentum dependent distribution, Machine learning
Benchmarking Nuclear Matrix Elements of $0\nu \beta \beta $ Decay with High-Energy Nuclear Collisions
Research article | Neutrinoless double beta decay | 2025-07-08 06:00 EDT
Yi Li, Xin Zhang, Giuliano Giacalone, and Jiangming Yao
Reducing uncertainties in the nuclear matrix elements (NMEs) remains a critical challenge in designing and interpreting experiments aimed at discovering neutrinoless double-beta ($0\nu \beta \beta $) decay. Here, we identify a class of observables, distinct from those employed in low-energy nuclear structure applications, that are strongly correlated with the NMEs: momentum correlations among hadrons produced in high-energy nuclear collisions. Focusing on the $^{150}\mathrm{Nd}\rightarrow ^{150}\mathrm{Sm}$ transition, we combine a Bayesian analysis of the structure of $^{150}\mathrm{Nd}$ with simulations of high-energy $^{150}\mathrm{Nd}+^{150}\mathrm{Nd}$ collisions. We reveal prominent correlations between the NMEs and features of the quark-gluon plasma formed in these processes, such as spatial gradients and anisotropies, that are accessible via collective flow measurements. Our findings demonstrate collider experiments involving $0\nu \beta \beta $ decay candidates as a platform for benchmarking theoretical predictions of the NMEs.
Phys. Rev. Lett. 135, 022301 (2025)
Neutrinoless double beta decay, Nuclear many-body theory, Quark-gluon plasma
New Class of Three-Nucleon Forces and Their Implications
Research article | Chiral perturbation theory | 2025-07-08 06:00 EDT
Vincenzo Cirigliano, Maria Dawid, Wouter Dekens, and Sanjay Reddy
We identify a new class of three-nucleon forces that arises in the low-energy effective theory of nuclear interactions including pions. We estimate their contribution to the energy of neutron and nuclear matter and find that it can be as important as the leading-order three-nucleon forces previously considered in the literature. The magnitude of this force is set by the strength of the coupling of pions to two nucleons and is presently not well constrained by experiments. The implications for nuclei, nuclear matter, and the equation of state of neutron matter are briefly discussed.
Phys. Rev. Lett. 135, 022501 (2025)
Chiral perturbation theory, Nuclear astrophysics, Nuclear forces, Nuclear many-body theory, Nuclear matter in neutron stars, Nuclear structure & decays
Polariton Fluids as Quantum Field Theory Simulators on Tailored Curved Spacetimes
Research article | Exciton polariton | 2025-07-08 06:00 EDT
Kévin Falque, Adrià Delhom, Quentin Glorieux, Elisabeth Giacobino, Alberto Bramati, and Maxime J. Jacquet
A fluid made of light can simulate a black hole’s boundary, providing insights into the mysterious quantum phenomena that occur at such a boundary.
Phys. Rev. Lett. 135, 023401 (2025)
Exciton polariton, Polaritons, Quantum field theory, Quantum simulation, Polariton condensate, Superfluids
Imaging-based Quantum Optomechanics
Research article | Imaging & optical processing | 2025-07-08 06:00 EDT
C. M. Pluchar, W. He, J. Manley, N. Deshler, S. Guha, and D. J. Wilson
In active imaging protocols, information about an object is encoded into the spatial mode of a scattered photon. Recently the quantum limits of active imaging have been explored with levitated nanoparticles, which experience a multimode radiation pressure backaction (the photon recoil force) due to radiative scattering of the probe field. Here we extend the analysis of multimode backaction to compliant surfaces, accessing a broad class of mechanical resonators and fruitful analogies to quantum imaging. As an example, we consider imaging of the flexural modes of a membrane by sorting the spatial modes of a laser reflected from its surface. We show that backaction in this setting can be understood to arise from spatiotemporal photon shot noise, an effect that cannot be observed in single-mode optomechanics. We also derive the imprecision-backaction product in the limit of purely spatial (intermodal) coupling, revealing it to be equivalent to the standard quantum limit for single-mode optomechanical coupling. Finally, we show that optomechanical correlations due to spatiotemporal backaction can give rise to two-mode entangled light, providing a mechanism for entangling desired pairs of spatial modes. In conjunction with high-$Q$ nanomechanics, our findings point to new opportunities at the interface of quantum imaging and optomechanics, including sensors and networks enhanced by spatial mode entanglement.
Phys. Rev. Lett. 135, 023601 (2025)
Imaging & optical processing, Optomechanics, Quantum measurements, Quantum optics, Structured light, Micromechanical & nanomechanical oscillators
Wettability-Dependent Damping of Droplet Vibrations on Solid Surfaces
Research article | Capillary waves | 2025-07-08 06:00 EDT
Fei Zhang, Chunyu Zhang, Wanqiu Zhang, Yingjie Yu, Shuguang Zhao, Jingwei Chen, Jiaqi Cheng, Yuanpeng Zhang, Hang Ding, and Xinping Zhou
Oscillating sessile droplets on a plane, crucial in industrial applications like inkjet printing, spray cooling, and antifogging, present a long-standing challenge in determining viscous damping. Existing solutions are limited to first-order asymptotic approximations of hemispherical droplets, accounting only for viscous dissipation near the wall. Considering further the bulk dissipation that is usually neglected due to its higher-order effect, we obtain a two-term approximation of decay rates for pinned sessile droplets with different contact angles. We demonstrate that the two-term approximation effectively resolves discrepancies between predicted and observed dampings for viscosities in the range of practical interest, supported by experiments and simulations. The two-term approximation also explains why hydrophobic droplets possess much lower damping than hydrophilic ones, and offers a template for damping prediction formulas with potential viscosity measurement applications.
Phys. Rev. Lett. 135, 024001 (2025)
Capillary waves, Drop & bubble phenomena, Surface tension effects
Flat Elastic Disc Suspensions Are Indistinguishable from Solutions of Long Flexible Polymers within Planar Incompressible Flows
Research article | Non-Newtonian fluids | 2025-07-08 06:00 EDT
Fabian Hillebrand, Rebecca J. Hill, Mahdi Davoodi, Simon J. Haward, Amy Q. Shen, Robert J. Poole, and Stylianos Varchanis
We prove analytically that the two fundamental rheological equations for (elastic) disc suspensions and long flexible polymers, the so-called Oldroyd-A and -B models, respectively, predict the same flow and total stress fields in any planar incompressible flow. We illustrate this equivalence for creeping flow in a cross-slot channel and investigate differences arising from three-dimensional effects in a weakly elastic Taylor-Couette flow. Finally, we discuss implications for understanding elastic instabilities, controlling inertial turbulence, and deriving constitutive models for complex fluids.
Phys. Rev. Lett. 135, 024002 (2025)
Non-Newtonian fluids
Elastic Pseudoturbulence in Polymer Solutions
Research article | Bubble dynamics | 2025-07-08 06:00 EDT
Mithun Ravisankar and Roberto Zenit
We study the effects of polymer additives on pseudoturbulence induced by a swarm of bubbles rising in a quiescent fluid. We find that, even in the absence of background shear, beyond a critical polymer concentration, the energy spectra of velocity fluctuations in bubble-induced turbulence decay more steeply with respect to the wave number $k$. This new scaling is significantly steeper than the classical ${k}^{- 3}$ scaling observed for bubbles in Newtonian fluids; it is independent of the gas volume fraction in the inertial limit and occurs within the length scales between the bubble wake length and the bubble diameter. Furthermore, we provide quantitative evidence that the presence of polymers enhances the coherence of the flow, as revealed by Lagrangian stretching statistics, highlighting the significant role of polymer additives in modifying the characteristics of pseudoturbulence. Our findings demonstrate that viscoelastic effects can modulate turbulence even in shear-free environments, offering a new perspective on the role of elastic stresses in complex multiphase flows.
Phys. Rev. Lett. 135, 024003 (2025)
Bubble dynamics, Turbulent multiphase flows, Non-Newtonian fluids
Thermodynamics and Statistical Equilibrium of Large-Scale Hydroelastic Wave Turbulence
Research article | Classical statistical mechanics | 2025-07-08 06:00 EDT
Marlone Vernet and Eric Falcon
Experiments with turbulent waves show that energy spreads from small to large scales, producing a steady-state regime that can be described using classical thermodynamics.
Phys. Rev. Lett. 135, 024004 (2025)
Classical statistical mechanics, Elastic waves, Hydrodynamic waves, Waves and free surface flows, Weak turbulence, Nonequilibrium systems, Nonlinear waves, Data analysis, Imaging & optical processing
Perfect Superconducting Diode Effect in Altermagnets
Research article | FFLO | 2025-07-08 06:00 EDT
Debmalya Chakraborty and Annica M. Black-Schaffer
We investigate intrinsic superconducting diode effect in the unconventional superconducting state of $d$-wave altermagnets. We find large diode efficiencies in the wide-reaching finite-momentum pairing regimes of the phase diagram. Remarkably, even perfect diode efficiency of 100% can be obtained in the presence of an external magnetic field. We attribute the largest efficiencies to competition between multiple zero-momentum (BCS) and finite-momentum superconducting states, which is connected to a topological nodal-to-nodeless transition in altermagnets with magnetic field, making our results applicable to a wide range of altermagnets.
Phys. Rev. Lett. 135, 026001 (2025)
FFLO, Pair density wave, Spin-singlet pairing, Altermagnets, Diodes, Superconducting devices, Superconductivity, Unconventional superconductors, BCS theory, Bogoliubov-de Gennes equations, Lattice models in condensed matter, Mean field theory, Methods in superconductivity, Superconductors
Superlubric-Locked Transition of Twist Grain Boundaries in 3D Crystals
Research article | Friction | 2025-07-08 06:00 EDT
Jin Wang and Erio Tosatti
Properties of twist grain boundaries (TGB), long known structurally but not tribologically, are simulated under sliding and load, with Au(111) our test case. The load-free TGB moir'e is smooth and superlubric at incommensurate twists. Surprisingly, load provokes a first-order structural transformation, where the highest energy moir'e nodes are removed—an unexpected Aubry-type transition for which we provide a Landau theory leading to a full twist-load phase diagram. Upon frictional sliding, the transformation causes a superlubric-locked transition, with a huge friction jump, and irreversible plastic flow. The predicted phenomena are robust, also recovered in a Lennard-Jones lattice TGB, and not exclusive to gold or to metals. Both superlubricity and strong Aubry locking hold promises for studies and applications in micro and nano mechanics and devices.
Phys. Rev. Lett. 135, 026202 (2025)
Friction, Grain boundaries, Structural order parameter, Tribology, Solid-solid interfaces, Molecular dynamics
Overcoming Asymmetric Carrier Injection in III-Nitride Light-Emitting Diodes through Defect Engineering
Research article | Charge dynamics | 2025-07-08 06:00 EDT
Yuxin Yang, Zhiming Shi, Shunpeng Lv, Hang Zang, Xiaobao Ma, Feng Zhang, Yan Yu, Peng Han, Ke Jiang, Xiaolan Yan, Su-Huai Wei, Xiaojuan Sun, and Dabing Li
The rapid advancements in the semiconductor industry are often accompanied by a breakthrough in defect engineering. While defects usually hinder device performance, they can also offer new opportunities for manipulating semiconductor properties. In this Letter, we present an effective approach to solving the long-standing asymmetric injection of carriers problem in LEDs by introducing nitrogen vacancies (${V}{\mathrm{N}}$) at the GaN/AlN quantum well (QW) interface. The ${V}{\mathrm{N}}$ states function as ‘’steps’’ as well as sources of perturbation potential to improve the electron relaxation to the bottom of the conduction band through the electron-phonon (el-ph) coupling. The electron relaxation time (${\tau }{\text{e}}$), initially as long as 8.61 ps, was reduced to 0.15 ps, comparable to the ${\tau }{\mathrm{h}}$ (0.12 ps). Our work not only resolves a persistent bottleneck in GaN-based light sources but also offers a new perspective on utilizing defects to engineer carrier relaxation.
Phys. Rev. Lett. 135, 026402 (2025)
Charge dynamics, Defects, Density of states, Electron relaxation, LEDs
Efficient Projected Entangled Pair States Methods for Periodic Quantum Systems
Research article | Quantum spin liquid | 2025-07-08 06:00 EDT
Shaojun Dong, Chao Wang, Hao Zhang, Meng Zhang, and Lixin He
Projected entangled pair states (PEPS) are recognized as a potent tool for exploring two-dimensional quantum many-body systems. However, a significant challenge emerges when applying conventional PEPS methodologies to systems with periodic boundary conditions (PBCs), attributed to the prohibitive computational scaling with the bond dimension. This has notably restricted the study of systems with complex boundary conditions. To address this challenge, we have developed a strategy that involves the superposition of PEPS with open boundary conditions (OBCs) to treat systems with PBCs. This approach significantly reduces the computational complexity of such systems while maintaining their translational invariance and the PBCs. We benchmark this method against the Heisenberg model and the ${J}{1}\text{- }{J}{2}$ model, demonstrating its capability to yield highly accurate results at low computational costs, even for large system sizes. We further apply the method to study the Chern numbers of the hard-core Harper-Hofstadter model at different filling factors using twisted boundary conditions. This advancement significantly broadens the applicability of the PEPS approach, opening new avenues for studying a wide range of quantum many-body phenomena.
Phys. Rev. Lett. 135, 026501 (2025)
Quantum spin liquid, Strongly correlated systems, Tensor network methods
Exploring Novel Quantum Embedding Methods with Nonorthogonal Decomposition of Slater Determinants
Research article | Electronic structure | 2025-07-08 06:00 EDT
Yuhang Ai, Ze-Wei Li, and Hong Jiang
The Schmidt decomposition of quantum many-body states, which is the basis of many powerful quantum many-body techniques, relies on a partition of the whole system in terms of orthogonal local basis functions. We propose in this Letter a nonorthogonal decomposition of Slater determinants, which reduces to the conventional Schmidt decomposition in the orthogonal limit. The new decomposition provides a natural tool for building local correlation spaces when the orbitals are overlapping, which can be used to extend some existing embedding methods based on the Schmidt decomposition like density matrix embedding theory (DMET) to overlapping subsystem partitions to achieve greater flexibility and efficiency. We also propose a new quantum embedding strategy that bridges the ab initio model potential (AIMP) embedding and DMET, which circumvents the necessarity of a mean-field calculation of the whole system like AIMP, and is able to capture quantum entanglement like DMET.
Phys. Rev. Lett. 135, 026502 (2025)
Electronic structure, First-principles calculations, Molecular magnetism, Spin-orbit coupling, Ab initio calculations, Electron-correlation calculations
Instability of Metals with Respect to Strong Electron-Phonon Interaction
Research article | Electron-phonon coupling | 2025-07-08 06:00 EDT
Emil A. Yuzbashyan, Boris L. Altshuler, and Aniket Patra
We show that thermal equilibrium between conduction electrons and phonons becomes kinetically unstable when the renormalized electron-phonon coupling exceeds a certain threshold. We prove that negative electronic specific heat, ${C}{\mathrm{el}}<0$, is sufficient to trigger the instability. Specifically, the instability sets in as soon as the quasiparticle weight becomes negative over a range of energies, even before ${C}{\mathrm{el}}$ turns negative. This is an inherently nonequilibrium phenomenon, occurring prior to the formation of any equilibrium phase. Depending on the system, it can proceed along different pathways, ultimately resulting in a structural transition to an insulating or metallic state.
Phys. Rev. Lett. 135, 026503 (2025)
Electron-phonon coupling, Thermal properties, Metals, Nonequilibrium systems
3D Conformal Field Theories with $\mathrm{Sp}(N)$ Global Symmetry on a Fuzzy Sphere
Research article | Chern-Simons gauge theory | 2025-07-08 06:00 EDT
Zheng Zhou (周正) and Yin-Chen He
The quest to discover new 3D CFTs has been intriguing for physicists. For this purpose, fuzzy sphere regularization that studies interacting quantum systems defined on the lowest Landau level on a sphere has emerged as a powerful tool. In this Letter, we discover a series of new CFTs with global symmetry $\mathrm{Sp}(N)$ in the fuzzy sphere models that are closely related to the SO(5) deconfined phase transition, and are related to a $\mathrm{Sp}(N)/[\mathrm{Sp}(M)\times{}\mathrm{Sp}(N- M)]$ nonlinear sigma model with a Wess-Zumino-Witten term. We numerically verify the emergent conformal symmetry by observing the integer-spaced conformal multiplets, the quality of conformal generators, and studying the finite-size scaling of the conformality. We discuss possible candidates for these newly discovered CFTs, the most plausible ones being Chern-Simons-matter theories which have $N$ flavors of gapless bosons or fermions coupled to a non-Abelian [viz. Sp(1), Sp(2), etc.] Chern-Simons gauge field. Our Letter provides new avenues for studying interacting CFTs in 3D, possibly facilitating the nonperturbative study of critical gauge theories and previously undiscovered CFTs.
Phys. Rev. Lett. 135, 026504 (2025)
Chern-Simons gauge theory, Conformal field theory, Critical phenomena, Quantum field theory, Quantum phase transitions, Quantum many-body systems, Strongly correlated systems, Conformal symmetry, Exact diagonalization
Spontaneous Spin-Orbit Coupling Induced by Quantum Phonon Dynamics
Research article | Electron-phonon coupling | 2025-07-08 06:00 EDT
Xiangyu Zhang, Da Wang, and Congjun Wu
Spin-orbit coupling is a important focus of condensed matter physics as well as electron-phonon interaction. Traditionally spin-orbit coupling is regarded as a single-body effect arising from relativity, and electron-phonon interaction is often considered spin-independent. In this Letter, we bridge spin-orbit coupling and electron-phonon interaction, and propose a novel mechanism to dynamically generate spin-orbit coupling. Based on symmetry analysis, a spin-dependent electron-phonon coupling model is constructed, and is solved by sign-problem-free quantum Monte Carlo simulations. The phase diagram versus phonon frequency $\omega $ and coupling constant $\lambda $ is fully investigated. The spin-orbit coupling emerges as an order in the ground state for any $\lambda $ in the adiabatic limit, accompanied by a breathing mode of lattice distortion and a staggered loop spin current. This phase dominates in the entire range of $\omega $ with $\lambda <{\lambda }{\infty }$, a critical value in the $\omega \rightarrow \infty $ limit. At $\lambda >{\lambda }{\infty }$, the emergent spin-orbit coupling is suppressed as increasing $\omega $, and a phase transition occurs leading to charge-density-wave ordering degenerate with superconductivity. Our work opens up the possibility of hidden spin-orbit coupling in materials where it is otherwise forbidden by lattice symmetry and paves the way to explore possible materials for spintronics.
Phys. Rev. Lett. 135, 026505 (2025)
Electron-phonon coupling, Spin current, Spin-orbit coupling, Quantum Monte Carlo
Magnetic Field Induced Quantum Metric Dipole in Dirac Semimetal ${\mathrm{Cd}}{3}{\mathrm{As}}{2}$
Research article | Electrical properties | 2025-07-08 06:00 EDT
Tong-Yang Zhao, An-Qi Wang, Zhen-Tao Zhang, Zheng-Yang Cao, Xing-Yu Liu, and Zhi-Min Liao
The quantum geometry, comprising Berry curvature and quantum metric, plays a fundamental role in governing electron transport phenomena in solids. Recent studies show that the quantum metric dipole drives scattering-free nonlinear Hall effect in topological antiferromagnets, prompting the questions of whether this effect can occur in nonmagnetic systems and be externally tuned by a magnetic field. Our work addresses these frontiers by demonstrating that the quantum metric dipole is actively tuned by an external magnetic field to generate a time-reversal-odd nonlinear Hall response in a nonmagnetic topological Dirac semimetal ${\mathrm{Cd}}{3}{\mathrm{As}}{2}$. Alongside the well-known chiral-anomaly-induced negative longitudinal magnetoresistance, an exotic nonlinear planar Hall effect emerges with increasing magnetic field. Careful scaling analysis indicates that this nonlinear planar Hall effect is controlled by the magnetic-field-modulated quantum metric dipole. Constructing a $k\cdot{}p$ effective model of the Dirac bands under Zeeman and orbital coupling, we derive the evolution of the quantum metric dipole as a function of the magnetic field, providing a comprehensive explanation of the experimental results. Our results establish a band-structure-based strategy for engineering nonlinear magnetotransport in nonmagnetic materials via the quantum metric dipole, opening a pathway toward magnetic-field–tunable nonlinear quantum devices.
Phys. Rev. Lett. 135, 026601 (2025)
Electrical properties, Geometric & topological phases, Dirac semimetal, Transport techniques
Internal Entropy of Non-Abelian Anyons from Heat Current through a Tunneling Barrier
Research article | Anyons | 2025-07-08 06:00 EDT
Noam Schiller, Hiromi Ebisu, Gil Refael, and Yuval Oreg
The effective internal entropy of non-Abelian anyons, such as those that arise in the fractional quantum Hall state at filling factor 5/2, manifests in the heat current through a tunneling barrier.
Phys. Rev. Lett. 135, 026602 (2025)
Anyons, Entanglement entropy, Fractional quantum Hall effect
Quantum Confining Excitons with an Electrostatic Moir'e Superlattice
Research article | Excitons | 2025-07-08 06:00 EDT
Liuxin Gu, Lifu Zhang, Sam Felsenfeld, Beini Gao, Rundong Ma, Suji Park, Houk Jang, Takashi Taniguchi, Kenji Watanabe, and You Zhou
Quantum confining excitons has been a persistent challenge in the pursuit of strong exciton interactions and quantum light generation. Unlike electrons, which can be readily controlled via electric fields, imposing strong nanoscale potentials on excitons to enable quantum confinement has proven challenging. In this Letter, we utilize piezoelectric force microscopy to image the domain structures of twisted hexagonal boron nitride ($h- \mathrm{BN}$), revealing evidence of strong in-plane electric fields at the domain boundaries. By placing a monolayer ${\mathrm{MoSe}}_{2}$ only 1 to 2 nm away from the twisted $h- \mathrm{BN}$ interface, we observe energy splitting of neutral excitons and Fermi polarons by several millielectronvolts at the moir'e domain boundaries. We attribute such observations to excitons confined in a nanoscale one-dimensional electrostatic potential created by the strong in-plane electric fields at the moir'e domain boundaries. Intriguingly, this 1D quantum confinement results in pronounced polarization anisotropy in the excitons’ reflection and emission, persistent to temperatures as high as $\sim 80\text{ }\text{ }\mathrm{K}$. These findings open new avenues for exploring and controlling strongly interacting excitons for classical and quantum optoelectronics.
Phys. Rev. Lett. 135, 026901 (2025)
Excitons, 2-dimensional systems, Quantum wires, Transition metal dichalcogenides, Twisted heterostructures
Deep Generative Modeling of the Canonical Ensemble with Differentiable Thermal Properties
Research article | Phase transitions | 2025-07-08 06:00 EDT
Shuo-Hui Li, Yao-Wen Zhang, and Ding Pan
By incorporating a differentiable temperature parameter an accurate one-shot simulation across a continuous range of temperature is achieved for variational modeling of a canonical ensemble.
Phys. Rev. Lett. 135, 027301 (2025)
Phase transitions, Classical spin models, Lattice models in statistical physics, Ising model, Neural network simulations, Numerical approximation & analysis, Variational approach, XY model
Physical Review X
Evidence for the Helicity Barrier from Measurements of the Turbulence Transition Range in the Solar Wind
Research article | Magnetohydrodynamic turbulence | 2025-07-08 06:00 EDT
J. R. McIntyre, C. H. K. Chen, J. Squire, R. Meyrand, and P. A. Simon
Data from NASA’s Parker Solar Probe reveal that a barrier to the transfer of energy often forms in the solar wind, limiting energy reaching small scales and helping explain why solar wind protons are hotter than electrons.
Phys. Rev. X 15, 031008 (2025)
Magnetohydrodynamic turbulence, Plasma turbulence, Plasma waves, Magnetized plasma, Solar wind, Electric & magnetic plasma measurements
Quantum Control of a Single ${\mathrm{H}}_{2}^{+}$ Molecular Ion
Research article | Atomic & molecular structure | 2025-07-08 06:00 EDT
D. Holzapfel, F. Schmid, N. Schwegler, O. Stadler, M. Stadler, A. Ferk, J. P. Home, and D. Kienzler
A helper ion enables full quantum control of a single H2+ ion by transferring quantum information through shared motion, allowing precise state preparation and high-resolution spectroscopy.
Phys. Rev. X 15, 031009 (2025)
Atomic & molecular structure, Fine & hyperfine structure, Quantum control, Quantum metrology, Quantum nondemolition measurement, Molecules, Trapped ions, Atom & ion trapping & guiding, Molecule trapping & guiding, Single molecule techniques, Spectroscopy
Review of Modern Physics
Colloquium: Quantum properties and functionalities of magnetic skyrmions
Research article | Frustrated magnetism | 2025-07-08 06:00 EDT
Alexander P. Petrović, Christina Psaroudaki, Peter Fischer, Markus Garst, and Christos Panagopoulos
Skyrmions are topological field configurations that were first discussed in the context of high-energy theory. In recent years, skyrmionic spin patterns in solid-state systems have received much attention, in part for their promising application potential. This Colloquium discusses quantum-mechanical aspects of such magnetic skyrmions, both for the interactions that underlie skyrmion formation and for quantum features of the skyrmions themselves.
Rev. Mod. Phys. 97, 031001 (2025)
Frustrated magnetism, Magnons, Quantum algorithms & computation, Quantum information with solid state qubits, Skyrmions, Spin dynamics, Topological quantum computing, Noncollinear magnets
arXiv
Dynamic Plastic Deformation Delocalization in FCC Solid Solution Metals
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Dhruv Anjaria, Milan Heczko, Daegun YoU, Mathieu Calvat, Shuchi Sanandiya, Maik Rajkowski, Aditya Srinivasan Tirunilai, Huseyin Sehitoglu, Guillaume Laplanche, J.C. Stinville
Metallic materials undergo irreversible deformation under mechanical loading, leading to intense local plastic localization that reduces their mechanical performance. We identify a new mechanism of plastic deformation localization that dynamically promotes the homogenization of plasticity in face-centered cubic solid solution-strengthened metallic alloys. We observe that this mechanism occurs within a narrow range of stacking fault energies and involves competing deformation between nanoscale twinning and slip. This phenomenon is attributed to a new mechanism referred to as dynamic plastic deformation delocalization, which opens a new design space for enhancing the mechanical performance of metallic materials. We demonstrate that the activation of this mechanism has a significant impact on fatigue properties, greatly enhancing fatigue strength when it occurs.
Materials Science (cond-mat.mtrl-sci)
Grain Size and Temperature-Dependent Response of 5-mol% Gd-Doped Ceria to Swift Heavy Ion Irradiation with 80 MeV Ag and 120 MeV Au Ions
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Waseem Ul Haq, V. Grover, Sanjay Kedia, Santanu Ghosh
The response of 5-mol% Gd-doped ceria to swift heavy ion beam irradiation has been studied to observe the effects of changes in ion energies and environmental temperature. The study involved irradiating two different grain sizes (nano and bulk) with two different ion energies: 80 MeV Ag and 120 MeV Au. Additionally, a comprehensive analysis of Gd-doped ceria’s response to ion beam irradiation at high temperatures (1000 K) was conducted, taking into account the effect of grain size dependency. Based on GIXRD and Raman spectroscopy, it is evident that electronic excitation from 80 MeV Ag and 120 MeV Au ions at a fluence $ 1 \times 10^{14}$ ions/cm$ ^2$ caused damage to Gd-doped ceria samples. However, bulk grain size shows significant stability against SHI in all cases. These findings align with thermal spike simulations and indicate the formation of ion tracks due to electronic excitation by Swift Heavy Ion beam irradiation.
Materials Science (cond-mat.mtrl-sci)
The Symmetry Taco: Equivalences between Gapped, Gapless, and Mixed-State SPTs
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Marvin Qi, Ramanjit Sohal, Xie Chen, David T. Stephen, Abhinav Prem
Symmetry topological field theory (SymTFT), or topological holography, offers a unifying framework for describing quantum phases of matter and phase transitions between them. While this approach has seen remarkable success in describing gapped and gapless pure-state phases in $ 1+1$ d, its applicability to open quantum systems remains entirely unexplored. In this work, we propose a natural extension of the SymTFT framework to mixed-state phases by introducing the \textit{symmetry taco}: a bilayer topological order in $ 2+1$ d whose folded geometry naturally encapsulates both strong and weak symmetries of the $ 1+1$ d theory. We use this perspective to identify a series of correspondences, including a one-to-one map between intrinsically gapless SPTs (igSPTs) and certain gapped SPTs, and a mapping between igSPTs and intrinsically average SPTs (iASPTs) arising in $ 1+1$ d mixed states. More broadly, our framework yields a classification of short-range correlated $ G$ -symmetric Choi states in $ 1+1$ d, provides a route for systematically generating mixed-state SPTs via local decoherence of igSPTs, and allows us to identify a new mixed-state ``anomaly”. Besides folding in mixed-state phases into the SymTFT paradigm, the symmetry taco opens new avenues for exploring dualities, anomalies, and non-equilibrium criticality in mixed-state quantum matter.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
37 pages, 6 figures
Thermal SU(2) lattice gauge theory for the pseudogap and the transition to $d$-wave superconductivity in the cuprates
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Harshit Pandey, Maine Christos, Pietro M. Bonetti, Ravi Shanker, Sayantan Sharma, Subir Sachdev
We study a square lattice SU(2) gauge theory with link variables $ U$ , formulated to describe the intermediate temperature pseudogap metal phase of underdoped cuprates of hole density $ p$ , and its evolution into nodal $ d$ -wave superconductivity upon cooling. The theory features two fermionic matter sectors: one consists of SU(2)-gauge-neutral, electron-like quasiparticles forming hole pockets; the other is a critical quantum spin liquid composed of electrically neutral spinons, carrying spin $ S = 1/2$ , Dirac nodes, and transforming in the fundamental representation of the SU(2) gauge group. These sectors interact via a Yukawa coupling to a spinless Higgs boson $ B$ , which carries electric charge $ +e$ and also transforms under the fundamental representation of SU(2). The theory arises from a canonical transformation of the square lattice Hubbard model and a pair of ancilla qubits on each site, along with a specific choice of the spin liquid. We employ a Born-Oppenheimer-type approximation: thermal fluctuations of the bosons $ B$ and $ U$ are treated classically, while the fermions are fully quantum. Monte Carlo simulations of an effective boson energy functional are consistent with a Kosterlitz-Thouless transition involving $ h/(2e)$ vortices, driving the onset of $ d$ -wave superconductivity. Each vortex is surrounded by a halo of charge order, consistent with scanning tunneling microscopy observations by Hoffman et al. (arXiv:cond-mat/0201348). Above the transition, the electron spectral function exhibits “Fermi arcs”, in agreement with ARPES data by Norman et al. (arXiv:cond-mat/9710163) and Shen et al. (Science 307, 901 (2005)). Our model also displays quantum oscillations with area $ p/8$ under a magnetic field, aligning with recent evidence via the Yamaji effect by Chan et al. (arXiv:2411.10631).
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
Topological phase diagram of twisted bilayer graphene as a function of the twist angle
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Leonardo A. Navarro-Labastida, Pierre A. Pantaleon, Francisco Guinea, Gerardo G. Naumis
Twisted bilayer graphene (TBG) hosts a rich landscape of electronic phases arising from the interplay between strong electron-electron interactions and nontrivial band topology. While the flat bands near zero energy are central to many correlated phenomena, their interaction with higher-energy remote bands remains less understood. Here, we investigate these hybridization processes as a function of the twist angle and analyze their impact on the charge distribution, topological properties such as Chern number, quantum metric, and orbital magnetic energy. We identify multiple topological phase transitions between magic angles, driven by band inversions at high-symmetry points in momentum space. Notably, the central bands can exhibit phases with Chern numbers C = 2, revealing previously unreported topological states in TBG.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
13 pages, 8 figures. Comments are very welcome
Symmetry-determined generalized ferromagnetism in multi-valley electron fluids
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Vladimir Calvera, Erez Berg, Steven A. Kivelson
Quantum electronic fluids with spin and valley degrees of freedom have a correlation driven tendency to flavor polarization (generalized ferromagnetism). To first order in the long-range Coulomb interactions – i.e. in the Hartree-Fock approximation – spin and valley polarization exhibit a spurious degeneracy. We show that to second order – or more generally in the random-phase approximation – this degeneracy is lifted in a way that depends only on the underlying symmetry relating the two valleys. In two spatial dimensions, if the valleys are related by an $ n-$ fold rotation ($ n>2$ ) or by mirror reflection and each valley is invariant under $ C_2$ or time reversal (as is the case in AlAs quantum wells) then valley polarization is preferred. If the valleys are related by time reversal or by $ C_2$ rotation symmetry (as in multilayer graphene systems) then spin order is selected.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 + 13 pages, 5 figures
Interaction-enhanced quantum to classical crossover temperature in a Luttinger liquid
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
We study electrical and thermal transport in a one-dimensional Luttinger liquid coupled to a three-dimensional acoustic phonon in both the clean" (umklapp scattering) and dirty” (disorder scattering) limits using the memory matrix formalism. By explicitly incorporating the Debye cutoff on phonon frequencies, we consider the low and high temperature transport regimes. We find the crossover temperature separating these two regimes to be interaction-dependent, with repulsive interactions increasing the crossover temperature by at most an order of magnitude. This provides an illustration for how interactions can enhance the low-temperature scattering regime in an interacting Fermi system.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th)
20 pages, 3 figures
Jammed disks of two sizes in a channel: segregation driven by steric forces
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
Dan Liu, Michael Karbach, Gerhard Müller
Disks of two sizes are confined to a long and narrow channel. The axis and the plane of the channel are horizontal. The channel is closed off by pistons that freeze jammed microstates out of loose disk configurations, agitated randomly at calibrated intensity and subject to moderate pressure. Disk sizes and channel width are such that under jamming no disks remain loose and all disks touch one wall. The protocol permits disks to move past each other prior to jamming, which facilitates randomness in the sequence of large and small disks. We present exact results for the characterization of jammed macrostates including volume and entropy for given fractions of small and large disks as functions of energy parameters which depend on the jamming protocol. Our analysis divides the disk sequence of jammed microstates into overlapping tiles out of which we construct 17 species of statistically interacting quasiparticles. Jammed macrostates then depend on the fractions of small and large disks and on a dimensionless control parameter inferred from measures for expansion work against the pistons and intensity of random agitations. Two models are introduced for comparison of key technical aspects: one model emphasizes symmetry and the other mechanical stability. We distinguish regimes for the energy parameters that either enhance or suppress mixing of disk sizes in jammed macrostates. The latter case, if realizable, is a manifestation of grain segregation driven by steric forces alone, without directional bias.
Soft Condensed Matter (cond-mat.soft)
19 pages, 13 figures, 8 tables
Model-based study of a nanowire heating and dynamic axisymmetric necking by surface electromigration
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Axisymmetric solid-state necking of a single-crystal metallic nanowire in a thermal contact with a substrate and subjected to a surface electromigration current is accompanied by a local current crowding and a sharp rise of a resistivity of a wire material in a thinning neck. This results in a temperature spike at the neck, which feedback affects the necking via thermomigration and the temperature-dependent surface diffusivity of the adatoms. A model that incorporates these effects and couples the nonlinear dynamics of a wire temperature and a wire radius for a necking wire is presented. Conditions on the physical parameters are derived that ensure a straight wire is in the solid state prior to an onset of a morphological instability that ultimately breaks a wire via a pinch-off. The impacts of a wire radius and a wire length on the temperature spike at the break junction are studied.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Mathematical Physics (math-ph), Applied Physics (physics.app-ph)
Electronic transport and anti-super-Klein tunneling in few-layer black phosphorous
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Jorge Alfonso Lizarraga-Brito, Armando Arciniega-Gutiérrez, Yonatan Betancur-Ocampo, Thomas Stegmann
The electronic transport in few-layer black phosphorus (FLBP) nanoribbons is studied theoretically. The system is modeled on the basis of band-structures, which have been measured recently by $ \mu$ -ARPES experiments. We show that the anisotropic bands of FLBP leads to highly anisotropic transport properties; while the current in one direction can be rather focused, it can be strongly disperse in the orthogonal direction. The low-energy current is carried mainly in the central layer due to the vertical confinement of the electrons. In FLBP pn junctions, generated by the electrostatic potential of a gate contact in a certain region of the system, the electrons pass through the interface of the junction, if it is oriented along the zigzag direction of FLBP. If the junction is rotated by 90 degree and oriented along the armchair direction, the current is reflected completely for all angles of incidence and for a wide range of electron energies. This omni-directional total reflection is named anti-super-Klein tunneling as it is due to opposite pseudo-spins of the electrons in the two region of the pn junction. The effect of oxidation of the top layer of FLBP pn junctions is investigated and it is found that, while the current flow in the top layers is strongly suppressed, the anti-super-Klein tunneling persists.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
11 pages, 11 figures
Fast nanothermometry based on direct electron detection of electron backscattering diffraction patterns
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Ryan Gnabasik, Razan O. Nughays, Ashlynn Overholser, Vijay Kumar, Shantal Adajian, Nicolò Maria della Ventura, Daniel S. Gianola, Bolin Liao
Accurate temperature measurement at the nanoscale is crucial for thermal management in next-generation microelectronic devices. Existing optical and scanning-probe thermometry techniques face limitations in spatial resolution, accuracy, or invasiveness. In this work, we demonstrate a fast and non-contact nanothermometry method based on temperature-induced changes in electron backscattering diffraction (EBSD) patterns captured by a high-performance direct electron detector within a scanning electron microscope (SEM). Using dynamical electron simulations, we establish the theoretical temperature sensitivity limits for several semiconductors (Si, Ge, GaAs, and GaN), showing that thermal diffuse scattering (TDS) leads to a measurable smearing of Kikuchi bands in the EBSD patterns. We develop a Fourier analysis method that captures these subtle changes across the full diffraction pattern, achieving a simulated temperature sensitivity of approximately 0.15% per K. Experimental results on silicon confirm a sensitivity of 0.14% per K and achieve a 13-K temperature uncertainty with a 10-second acquisition time, and enable spatial temperature mapping under thermal gradients. Our approach offers a pathway toward practical and high-resolution thermal mapping directly in SEMs, expanding the toolbox for device-level thermal diagnostics.
Materials Science (cond-mat.mtrl-sci), Instrumentation and Detectors (physics.ins-det)
20 pages, 6 figures
Proximity effect and p-wave superconductivity in s-wave superconductor/helimagnet heterostructures
New Submission | Superconductivity (cond-mat.supr-con) | 2025-07-09 20:00 EDT
G. A. Bobkov, A. V. Kornev, A. M. Bobkov, I. V. Bobkova
It is known that in contrast to homogeneous ferromagnetism helical magnetism is compatible with superconductivity and causes only weak suppressive effect on superconducting critical temperature. Despite this fact it induces p-wave triplet superconducting correlations in homogeneous superconducting systems with intrinsic helical magnetism. The combination of these two facts indicates a high potential for the application of such systems in disspationless spintronics. For this reason here we investigate the proximity effect in atomically thin superconductor/helical (conical) magnet heterostructures (SC/HM). It is shown that in SC/HM heterostructures the strength of the proximity effect and, in particular, amplitude of p-wave triplet superconductivity and the degree of superconductivity suppression are complex functions of the magnet exchange field and filling factors of the magnet and the superconductor. Further we demonstrate that $ p$ -wave correlations ensure transport spin supercurrent flow in the SC/HM heterostructure with conical magnets and unveil the physical relationship between the transport spin supercurrent, degree of the magnet conicity and internal structure of p-wave correlations in the momentum space.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
MBFormer: A General Transformer-based Learning Paradigm for Many-body Interactions in Real Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Bowen Hou, Xian Xu, Jinyuan Wu, Diana Y. Qiu
Recently, radical progress in machine learning (ML) has revolutionized computational materials science, enabling unprecedentedly rapid materials discovery and property prediction, but the quantum many-body problem – which is the key to understanding excited-state properties, ranging from transport to optics – remains challenging due to the complexity of the nonlocal and energy-dependent interactions. Here, we propose a symmetry-aware, grid-free, transformer-based model, MBFormer, that is designed to learn the entire many-body hierarchy directly from mean-field inputs, exploiting the attention mechanism to accurately capture many-body correlations between mean-field states. As proof of principle, we demonstrate the capability of MBFormer in predicting results based on the GW plus Bethe Salpeter equation (GW-BSE) formalism, including quasiparticle energies, exciton energies, exciton oscillator strengths, and exciton wavefunction distribution. Our model is trained on a dataset of 721 two-dimensional materials from the C2DB database, achieving state-of-the-art performance with a low prediction mean absolute error (MAE) on the order of 0.1-0.2 eV for state-level quasiparticle and exciton energies across different materials. Moreover, we show explicitly that the attention mechanism plays a crucial role in capturing many-body correlations. Our framework provides an end-to-end platform from ground states to general many-body prediction in real materials, which could serve as a foundation model for computational materials science.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
The role of electron interactions in a failed insulator revealed by shot noise
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Mateusz Szurek, Hanqiao Cheng, Zilu Pang, Yiou Zhang, Sergei Urazhdin
In materials known as failed insulators, electrical resistivity increases as temperature decreases, yet does not diverge - a phenomenon inconsistent with single-particle theories. We investigate the origin of this behavior by measuring shot noise in nanojunctions of nitrogen-doped beta-Ta, a prototypical failed insulator. Junctions as short as 8 nanometers exhibit hot-electron shot noise, indicating strong electron interactions. We show that charge hopping mediated by these interactions explains the anomalous electronic properties. Our findings open new avenues for exploiting electron interactions in spin-orbitronic and superconducting applications of failed insulators.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
comments and suggestions are welcome
Revealing the Void-Size Distribution of Silica Glass using Persistent Homology
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-07-09 20:00 EDT
Achraf Atila, Yasser Bakhouch, Zhuocheng Xie
Oxide glasses have proven to be useful across a wide range of technological applications. Nevertheless, their medium-range structure has remained elusive. Previous studies focused on the ring statistics as a metric for the medium-range structure, which, however, provides an incomplete picture of the glassy structure. Here, we use atomistic simulations and state-of-the-art topological analysis tools, namely persistent homology (PH), to analyze the medium-range structure of the archetypal oxide glass (Silica) at ambient temperatures and with varying pressures. PH presents an unbiased definition of loops and voids, providing an advantage over other methods for studying the structure and topology of complex materials, such as glasses, across multiple length scales. We captured subtle topological transitions in medium-range order and cavity distributions, providing new insights into glass structure. Our work provides a robust way for extracting the void distribution of oxide glasses based on persistent homology.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Materials Science (cond-mat.mtrl-sci)
Main + Supp
Nonvolatile Nematic Order Manipulated by Strain and Magnetic Field in a Layered Antiferromagnet
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Zili Feng, Weihang Lu, Tao Lu, Fangyan Liu, Joseph R. Sheeran, Mengxing Ye, Jing Xia, Takashi Kurumaji, Linda Ye
The operation mechanism of nematic liquid crystals lies in the control of their optical properties by the orientation of underlying nematic directors. In analogy, electronic nematicity refers to a state whose electronic properties spontaneously break rotation symmetries of the host crystalline lattice, leading to anisotropic electronic properties. In this work, we demonstrate that the layered antiferromagnet CoTa$ _3$ S$ _6$ exhibits a switchable nematic order, evidenced by the emergence of both resistivity anisotropy and optical birefringence. This nematic state sets in at a temperature $ T^\ast$ distinct from that of the antiferromagnetic transitions in the system, indicating a separate symmetry-breaking mechanism. The nematic order can be manipulated either by an in-plane rotation symmetry-breaking strain or in-plane magnetic field, with the latter exhibiting a pronounced non-volatile memory effect. Remarkably, we find that the broken three-fold rotation symmetry in electronic transport is restored with a moderate out-of-plane field. We hypothesize that the nematicity is of electronic origin and emerges from instabilities associated with van Hove singularities. The resulting phase diagram points to an intertwined interplay between the electronic nematicity and the proposed underlying collinear and non-coplanar spin orders. Our findings establish CoTa$ _3$ S$ _6$ as a versatile antiferromagnetic platform with highly tunable functionalities arising from the breaking of rotational, time-reversal, and inversion symmetries.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 4 figures
Elementary Steps of Energy Conversion in Strongly Correlated Systems: Beyond Single Quasiparticles and Rigid Bands
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
V. Moshnyaga, Ch. Jooss P. E. Blöchl, V. Bruchmann-Bamberg, A. Dehning, L. Allen-Rump, C. Hausmann, M. Krüger, A. Rathnakaran, S. Rajpurohit, D. Steil, C. Flathmann, J. Hoffmann, M. Seibt, C. Volkert
Energy conversion in materials can be considered as a sequence of elementary steps initiated by a primary excitation. While these steps are quite well understood in classical semiconductors in terms of quasiparticle (QP) excitations and interactions, their understanding in strongly correlated materials is still elusive. Here, we review the progress which has been achieved over recent years by studies of manganite perovskite oxides as a model system for materials with strong correlations. They show a subtle interplay of different types of correlations, i.e., electron-phonon, electron-electron and spin-spin, resulting in rich physical phenomena due to competition between different ground states accompanied by temperature- and field-induced phase transitions. They strongly impact various types of energy conversion and transport processes including friction at surfaces, thermal transport, time-, energy- and power-dependent optical excitations as well as photovoltaic energy conversion. The underlying microscopic processes can be broken down to the behavior of the low-energy thermal and high-energy optical excitations, their interactions, transport and conversion which are theoretically analyzed by using models of interacting and tunable QPs: Their nature and interactions can change during excitation, transport and phase transitions, thus modifying electronic structure. At sufficiently high stimulation, QP excitations can even induce or actuate phase transitions. As a result, we obtained a comprehensive understanding of energy conversion steps going far beyond single QP pictures and rigid band approximations well-known for conventional semiconductors.
Strongly Correlated Electrons (cond-mat.str-el)
Identifying Exceptional Points in Two-Dimensional Excitons Coupled to an Open Optical Cavity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Ben Johns, Nitin Yadav, Anand Vinod, Kuljeet Kaur, Jino George
Strong coupling in the conventional sense requires that the Rabi cycling process between two interacting states is faster than other dissipation rates. Some recent experimental findings show intriguing properties that were attributed to polaritonic states (e.g., plexcitons) even though the above criterion is not satisfied. Here, we theoretically predict and provide experimental evidence of polariton-like behavior in a system that does not show Rabi splitting. The photoluminescence of an exciton-cavity system consisting of a two-dimensional exciton monolayer (tungsten disulfide, WS2) coupled to a planar, open, one-mirror optical cavity configuration is studied. We experimentally observed a transition from the weak coupling regime crossing an exceptional point to form polariton-like states by varying the coupling strength and the cavity loss. Our observations are fully in agreement with a theoretical quasi-normal mode analysis, which predicts this transition and confirms the presence of exceptional points in the system. These results provide evidence that polaritonic effects can be experimentally observed even when the conventional strong coupling condition is not satisfied.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
2D materials, non-Hermitian photonics, strong coupling, polariton emission, quasi-normal modes, nanophotonics
Putative non-trivial topology in YNiSn$_{2}$ Dirac semimetal
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Gabriel S. Freitas, Kevin R. Pakuszewski, Alisson P. Machado, Henrique Pizzi, Fellipe B. Carneiro, Felipe S. Oliveira, Mario M. Piva, Eduardo M. Bittar, Yakov Kopelevich, Filip Ronning, Joe D. Thompson, Cris Adriano, Pascoal G. Pagliuso
In this work, we investigate the properties of single-crystalline YNiSn$ _{2}$ through x-ray powder diffraction, elemental analysis, electrical resistivity, magnetic susceptibility, and specific heat measurements. YNiSn$ {2}$ crystallizes in an orthorhombic structure within the Cmcm space group (63), forming plate-like crystals with the $ b$ axis oriented out of the plane. The compound exhibits weak Pauli paramagnetism with a susceptibility of $ \chi{0} = 2(3) \times 10^{-5}$ emu/mol-Oe and a small Sommerfeld coefficient of $ \gamma = 4$ mJ/mol$ \cdot$ K$ ^{2}$ , indicating a low density of states at the Fermi level. Notably, at 1.8 K, YNiSn$ _{2}$ displays a giant positive magnetoresistance of nearly 1000%, which increases quasi-linearly with the magnetic field up to $ B = 16$ T, alongside a field-induced metal-insulator-like crossover under applied magnetic fields $ >$ 3 T. Furthermore, highly anisotropic dHvA quantum oscillations suggest a two-dimensional electronic band character from which a low effective mass and a high Fermi velocity could be extracted.
Strongly Correlated Electrons (cond-mat.str-el)
Revealing THz optical signatures of Shiba-state-induced gapped and gapless superconductivity
New Submission | Superconductivity (cond-mat.supr-con) | 2025-07-09 20:00 EDT
F. Yang, R. Y. Fang, S. L. Zhang, L. Q. Chen
Understanding the interplay of superconductivity and magnetic disorder has been a long-standing challenge. Here we report a fully self-consistent calculation of the complex renormalization by exchange interactions and hence the complete phase diagram of conventional $ s$ -wave superconductors with magnetic impurities as well as the related physical properties including the optical response. We show that a small amount of magnetic disorder can drive the system into a gapless superconducting state, where the single-particle excitation gap vanishes whereas the superconducting order parameter $ \Delta_0$ remains finite. In this phase, the linear optical conductivity exhibits a finite absorption over the low-frequency regime, particularly for photon energies below the conventional threshold $ 2|\Delta_0|$ , even at low temperatures, in sharp contrast to the gapped state. The nonlinear response, however, remains coherent and is dominated by the Higgs-mode dynamics rather than gapless quasiparticle background. These findings reveal a fundamental distinction between dissipative single-particle excitations and coherent collective dynamics of the condensate, a feature likely general to other gapless superconductors, and introduces a fundamentally different detection scheme, using THz spectroscopy to probe the signatures of Shiba states.
Superconductivity (cond-mat.supr-con)
Altermagnetism-induced non-collinear superconducting diode effect and unidirectional superconducting transport
New Submission | Superconductivity (cond-mat.supr-con) | 2025-07-09 20:00 EDT
Current studies of non-reciprocal superconducting (SC) transport have centered on the forward-backward asymmetry of the critical current measured along a single axis. In most realizations, this diode effect is achieved via introducing ferromagnetism or applying an external magnetic field, which drives system into an effective Fulde-Ferrell (FF) state but often at the cost of severely suppressing the SC gap and thus compromising device robustness. Here we propose and theoretically demonstrate that coupling a conventional $ s$ -wave SC thin film to a $ d$ -wave altermagnet offers a more resilient alternative. The momentum-dependent spin splitting inherent to altermagnets induces a non-collinear SC-diode effect in the BCS state, with the critical-current anisotropy exhibiting a fourfold ($ C_4$ ) symmetry. Upon entering the FF state at large splitting, this anisotropy gradually evolves into a unidirectional ($ C_1$ ) pattern. Crucially, the FF pairing momentum locks to the discrete crystal axes, eliminating the rotational Goldstone mode and preserving a sizable SC gap without any abrupt or significant suppression. These combined features make the altermagnetic proximity an appealing platform to engineer symmetry-protected, energy-efficient and programmable SC diodes for next-generation electronic devices.
Superconductivity (cond-mat.supr-con)
Direct observation of the compression behavior of polystyrene microbeads in a diamond anvil cell
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
Haruto Moriguchi, Ken Niwa, Masashi Hasegawa, Yusuke Koide, Takato Ishida, Takashi Uneyama, Yuichi Masubuchi
The pressure dependence of the bulk modulus of glassy polystyrene (PS) was measured in the relatively high-pressure regime, up to 6 GPa, at ambient temperature. For the measurements, PS microbeads were immersed in a pressure medium consisting of a mixture of methanol and ethanol, and the sample was placed in a diamond anvil cell capable of generating high and hydrostatic pressure. The volume change of the PS beads was observed under an optical microscope. The results demonstrated that the volume change in this study is consistent with an equation of state determined from the earlier studies in the low-pressure range up to 0.2 GPa. The bulk modulus was obtained as the derivative of the microbead volume with respect to pressure, and compared with the earlier data obtained from Brillouin spectroscopy.
Soft Condensed Matter (cond-mat.soft)
10 pages, 4 figures
Self-organized first-order transition from foreshock to mainshock in earthquake sequences induced by heat, fluid pressure, and porosity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Takehito Suzuki, Hiroshi Matsukawa
Earthquake cycles are studied by taking into account the interactions among slip, fluid pressure, temperature, and porosity on the fault planes, which are known to play a crucial role in earthquake dynamics. The spring-block model with a single block is employed. A first-order transition from foreshock to mainshock occurring spontaneously in earthquake sequences is discovered both analytically and numerically. This transition is induced by these interactions. It is shown that the function of the slip distance $ u$ , $ F(u)$ , defined as the sum of the difference between the energies stored in the driving spring before and after the slippage, and the energy dissipated during the slippage, governs the transition. The equation, $ F(u)=0$ , represents the energy balance before and after the slippage, and the solution $ u=u_f$ describes the realized slip distance for each slippage event. The solutions discontinuously transition from small to large slippages in the sequence of earthquakes. This transition can be interpreted to be a self-organized first-order transition from small to large slippages. The former slippage is governed by pore generation, whereas the latter is governed by thermal pressurization. A phase diagram of the foreshocks and mainshocks, which is also considered a phase diagram of slow and fast earthquakes, is obtained.
Materials Science (cond-mat.mtrl-sci), Geophysics (physics.geo-ph)
20 pages, 7 figures
published Eur. Phys. J. B (2025) 98:67
On void formation during the simulated tensile testing of polymer-filler particle composites
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
John J. Karnes, Supun S. Mohottalalage, Amitesh Maiti, Andrew P. Saab, Todd H. Weisgraber
We simulate a series of model polymer composites, composed of linear polymer strands and spherical, monodisperse filler particles (FP). These molecular dynamics simulations implement a coarse-grained, bead-spring force field and we vary several formulation parameters to study their respective influences on material properties. These parameters include FP radius, FP volume fraction, temperature, and the polymer-polymer, FP-FP, and polymer-FP interaction potentials. Uniaxial extension of the simulation cells allows direct comparison of mechanical reinforcement (or weakening) provided by the FP. We focus on the formation of microscopic voids during simulated tensile testing of glassy polymer composites and quantify how the characteristic spatial and morphological arrangement of these voids is a function of interaction potentials used in the simulation. We discuss the implications of these findings in the context of polymer composite design and formulation.
Soft Condensed Matter (cond-mat.soft), Computational Physics (physics.comp-ph)
Revisiting Multi-Wave Resonance in Classical Lattices: Quasi-Resonances, Not Exact Resonance, Govern Energy Redistribution
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Wei Lin, Yong Zhang, Hong Zhao
The multi-wave exact resonance condition is a fundamental principle for understanding energy transfer in condensed matter systems, yet the dynamical evolution of waves satisfying this condition remains unexplored. Here, we reveal that the multi-wave resonant kinetic equations possess distinctive symmetry properties that preferentially induce energy equalization between counter-propagating waves of identical frequency. This initial equalization disrupts the exact resonance condition, rendering it dynamically invalid. We further demonstrate that nonlinearity-mediated multi-wave quasi-resonances–not exact resonances–overn energy transfer and drive the system toward thermalization. Crucially, the strength of exact resonances decays with increasing system size, while quasi-resonance strength grows. Moreover, exact resonance strength remains independent of nonlinearity, whereas quasi-resonance strength diminishes with reduced nonlinearity. These observations provide additional evidence supporting the aforementioned conclusion while elucidating the size-dependent thermalization characteristics in lattice systems.
Statistical Mechanics (cond-mat.stat-mech), Chaotic Dynamics (nlin.CD), Classical Physics (physics.class-ph)
12 pages, 5 figures
MP-ALOE: An r2SCAN dataset for universal machine learning interatomic potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Matthew C. Kuner, Aaron D. Kaplan, Kristin A. Persson, Mark Asta, Daryl C. Chrzan
We present MP-ALOE, a dataset of nearly 1 million DFT calculations using the accurate r2SCAN meta-generalized gradient approximation. Covering 89 elements, MP-ALOE was created using active learning and primarily consists of off-equilibrium structures. We benchmark a machine learning interatomic potential trained on MP-ALOE, and evaluate its performance on a series of benchmarks, including predicting the thermochemical properties of equilibrium structures; predicting forces of far-from-equilibrium structures; maintaining physical soundness under static extreme deformations; and molecular dynamic stability under extreme temperatures and pressures. MP-ALOE shows strong performance on all of these benchmarks, and is made public for the broader community to utilize.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI), Computational Physics (physics.comp-ph)
To download the dataset and associated files, see this https URL
Direct observation of locally modified excitonic effect within a moiré unit cell in twisted bilayer graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Ming Liu, Ryosuke Senga, Masanori Koshino, Yung-Chang Lin, Kazu Suenaga
Bilayer graphene, forming moiré superlattices, possesses distinct electronic and optical properties derived from the hybridization of energy band and the emergence of van Hove singularities depending on its twist angle. Extensive research has been conducted on the global characteristics of moiré superlattice induced by long-range periodicity. However, limited attention has been given to the local properties within a moiré unit cell, which undoubtedly differ due to the variations in three-dimensional atomic arrangement. Here we demonstrate the highly localized excitations of carbon 1s electrons to unoccupied van Hove singularities in a twisted bilayer graphene using an electron energy loss spectroscopy based on a monochromated transmission electron microscope. The core-level excitations associated with the van Hove singularities show a systematic twist angle dependence which is analogous to the optical excitations. Furthermore, local variations in those core-level van Hove singularity peaks within a moiré unit cell have been corroborated for the first time, which can originate from core-exciton lifetimes and band modifications influenced by the local stacking geometry.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
33 pages with 4 figures for maintext and 5 pages with 3 figures for supporting information
ACS Nano 17 (2023) 18433-18440
Spin transport phenomena in junctions composed of a compensated ferrimagnet and a normal metal
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Xin Theng Lee, Takahiro Misawa, Mamoru Matsuo, Takeo Kato
Altermagnets and compensated ferrimagnets have attracted considerable attention as key building blocks in spintronics devices, owing to their dual advantages of ferromagnets and antiferromagnets. In particular, compensated ferrimagnets exhibit isotropic spin splitting in their electronic and magnon dispersions, despite having zero net magnetization. This characteristic feature enables spin transport phenomena analogous to those in ferromagnets. However, quantitative evaluations of such spin transport phenomena, particularly in comparison to conventional ferromagnets, remain unexplored. Here we investigate spin pumping and spin Seebeck effects in a junction between a compensated ferrimagnet and a normal metal using the non-equilibrium Green’s function method. We find that the isotropic spin splitting in magnon dispersions gives rise to spin transport phenomena similar to those observed in ferromagnets. Our results provide a solid theoretical foundation for the applications of exotic collinear antiferromagnets with spin splitting to spintronics devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
11 pages, 7 figures
Uncovering coupled ionic-polaronic dynamics and interfacial enhancement in Li$_x$FePO$_4$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Fengyu Xie, Yuxiang Gao, Ruoyu Wang, Zhicheng Zhong
Understanding and controlling coupled ionic-polaronic dynamics is crucial for optimizing electrochemical performance in battery materials. However, studying such coupled dynamics remains challenging due to the intricate interplay between Li-ion configurations, polaron charge ordering, and lattice vibrations. Here, we develop a fine-tuned machine-learned force field (MLFF) for Li$ _x$ FePO$ _4$ that captures coupled ion-polaron behavior. Our simulations reveal picosecond-scale polaron flips occurring orders of magnitude faster than Li-ion migration, featuring strong correlation to Li configurations. Notably, polaron charge fluctuations are further enhanced at Li-rich/Li-poor phase boundaries, suggesting a potential interfacial electronic conduction mechanism. These results demonstrate the capability of fine-tuned MLFFs to resolve complex coupled transport and provide insight into emergent ionic-polaronic dynamics in multivalent battery cathodes.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Defect migration and phase transformations in 2D iron chloride inside bilayer graphene
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Qiunan Liu, Haiming Sun, Yung-Chang Lin, Mahdi Ghorbani-Asl, Silvan Kretschmer, Chi-Chun Cheng, Po-Wen Chiu, Hiroki Ago, Arkady V. Krasheninnikov, Kazu Suenaga
The intercalation of metal chlorides, and particularly iron chlorides, into graphitic carbon structures has recently received lots of attention, as it can not only protect this two-dimensional (2D) magnetic system from the effects of the environment, but also substantially alter the magnetic, electronic, and optical properties of both intercalant and host material. At the same time, the intercalation can result in the formation of structural defects, or defects can appear under external stimuli, which can affect materials performance. These aspects have received so far little attention in the dedicated experiments. In this study, we investigate the behavior of atomic-scale defects in iron chlorides intercalated into bilayer graphene (BLG) by using scanning transmission electron microscopy (STEM) and first-principles calculations. We observe transformations between the FeCl2 and FeCl3 phases and elucidate the role of defects in the transformations. Specifically, three types of defects are identified: Fe vacancies in FeCl2 domains, Fe adatoms and interstitials in FeCl3 domains, each exhibiting distinct dynamic behaviors. We also observed a crystalline phase with an unusual stoichiometry of Fe5Cl18 which has not been reported before. Our findings not only advance the understanding of intercalation mechanism of 2D materials but also highlight the profound impact of atomic-scale defects on their properties and potential technological applications.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Chemical Physics (physics.chem-ph)
Unified Statistical Theory of Heat Conduction in Nonuniform Media
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
We present a theory of heat conduction that encompasses and extends the classical paradigm defined by Fourier law and the Kapitza interfacial conductance model. Derived from the Zwanzig projection operator formalism, our approach introduces a spatiotemporal kernel function of heat conduction, which governs the spatiotemporal response of the local heat flux in nonuniform media to surrounding temperature gradients while incorporating temporal memory effects. Our statistical analysis shows that memory, nonlocality, and interfacial temperature discontinuities emerge naturally from the microscopic coupling between two classes of irrelevant degrees of freedom: flux mode and nonlocal mode variables. Although these irrelevant variables are not directly observable at the macroscopic level, their integrated influence on the heat flux is fully encoded in the kernel function. In the diffusive limit, the kernel recovers and generalizes Fourier law by replacing the thermal conductivity with an infinite hierarchy of position dependent higher order tensors that capture nanoscale nonlocality. We also outline atomistic strategies for computing the spatiotemporal kernel in various classes of material media, enabling predictive modeling of heat transport in structurally complex and compositionally inhomogeneous systems. These include nanostructured, anisotropic, and interfacial materials where classical local models break down. Finally, the kernel function formalism is extensible to electronic, spin, or magnetic systems, providing a broadly applicable platform for next generation transport theory at ultrafast and nanoscale regimes.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
41 pages
Dissipative response of driven bead-spring-dashpot chains
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
The work dissipated in pulling a polymer chain with internal friction is numerically calculated by considering a sequence of $ N$ bead-spring-dashpots tethered at one end and being pulled at the other using a harmonic trap via linear and symmetric protocols. The variation of the dissipation with the chain length, pulling trap stiffness, and the internal friction parameter are examined in detail for both the protocols. In the limit of high trap stiffness: (i) the dissipation $ decreases$ with $ N$ for chains with internal friction, keeping all other parameters constant, and (ii) the relationship between the dissipation and internal friction parameter deviates from linearity as $ N$ is increased. Consequently, a closed-form expression between the dissipated work in driving a chain of spring-dashpots and the damping coefficient of a single dashpot can be written only for the case of $ N = 1$ [as shown in Phys. Rev. Res. $ \mathbf{2}$ , 013331 (2020)] and not for the general case of $ N > 1$ .
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
20 pages, 15 figures
Surface Reduction Boosts Free Electron Concentration in MXene for Enhanced Photothermal Performance
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Haoming Ding, Xiao Tong, Yong Zhang
The photothermal properties of MXenes originate from their high free electron concentration, which drives localized surface plasmon resonance (LSPR). However, their intrinsic electron concentration is limited by suboptimal d-orbital occupancy, while electronegative surface terminations actively deplete free electrons through orbital-selective withdrawal. Herein, we report a sodium (Na)-mediated surface reduction strategy in molten salts to transform Ti3C2Clx into electronically tunable Ti3C2. Specifically, Na atoms remove -Cl terminations to eliminate electron withdrawal and simultaneously inject electrons into the MXene lattice via a reduction reaction. This dual effect saturates Ti 3d-orbital vacancies while reducing surface coordination sites, achieving an increase in carrier concentration to 4.92-fold, an increase in mobility to 2.63-fold, and an enhancement in conductivity to 12.96-fold. Consequently, the optimized reduced MXene achieves a record photothermal conversion efficiency of 92.36% under 808 nm laser irradiation. As a proof-of-concept, a photothermal antibacterial woundplast with ultralow MXene content demonstrates a 91.39% bacterial kill rate. This work not only shows an effective way to tune the photothermal properties of MXenes but also inspires applications that require high electron concentration, such as energy storage, sensors, and electromagnetic interference shielding.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Revisiting the configurations of hydrogen impurities in SrTiO3: Insights from first-principles local vibration mode calculations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
The specific configurations of hydrogen impurities in SrTiO3 (STO) are still ambiguous. In this study, we systematically investigate the configurations and vibrational properties of hy-drogen impurities in cubic STO using first-principles local vibration mode calculations. Em-ploying the appropriate hybrid exchange correlation functional with the fraction of exact ex-change setting to 0.2, we revisit the interstitial hydrogen (Hi), Hi complexes (2Hi), and various intrinsic cation vacancy complexes with Hi, including VSr-Hi, VSr-2Hi, VTi-Hi, and VTi-2Hi. Comparison of the computed vibrational frequencies with experimental infrared absorption bands reveals that Hi, with a frequency of 3277 cm-1, is unlikely to account for the dominant absorption bands near 3500 cm-1. Instead, strontium vacancy complexes with interstitial hydro-gen (VSr-Hi and VSr-2Hi) exhibit vibrational frequencies that align with the main absorption bands, whereas titanium vacancy complex with two interstitial hydrogen (VTi-2Hi) corresponds to additional absorption bands around 3300 cm-1. These findings provide insights into the im-portance of hydrogen-related complexes in governing the electronic properties of STO, and meanwhile underscore the necessity of employing accurate exchange correlation functionals for reliable theoretical predictions of vibrational properties.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
5 figures
Real-space titration and manipulation of particle-like correlated electrons in doped Mott insulator
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Yanyan Geng, Haoyu Dong, Renhong Wang, Zilu Wang, Jianfeng Guo, Shuo Mi, Yan Li, Fei Pang, Rui Xu, Li Huang, Hong-Jun Gao, Wei Ji, Shancai Wang, Weichang Zhou, Zhihai Cheng
The localized (particle-like) correlated electrons deserve particular attention as they govern various exotic quantum phenomena, such as quantum spin liquids, Wigner crystals, and Mott insulators in correlated systems. However, direct observation and manipulation of these particle-like electrons at the atomic or single-electron scale remain highly challenging. Here, we successfully realize and directly visualize particle-like correlated electrons in 1T-TaS2 through hole doping. The potential-dependent local electronic structure of single particle-like electron is revealed by angle-resolved photoemission spectroscopy (ARPES), scanning tunneling spectroscopy (STS) combined with theoretical calculations. The complex correlated interactions including nearest-neighbor attractive interactions and many-body repulsive interactions are further demonstrated and discussed based on the spatial distribution of particle-like electrons. Furthermore, the tentative manipulation of the particle-like electrons is successfully achieved by the energy-excitation mechanism. Our results not only provide profound insights into particle-like electrons in correlated systems, but also establish a versatile platform for designing and controlling quantum states at the atomic scale.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
20 pages, 4 figures
Proxitaxis: an adaptive search strategy based on proximity and stochastic resetting
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Giuseppe Del Vecchio Del Vecchio, Manas Kulkarni, Satya N. Majumdar, Sanjib Sabhapandit
We introduce \emph{proxitaxis}, a simple search strategy where the searcher has only information about the distance from the target but not the direction. The strategy consists of three crucial components: (i) local adaptive moves with distance-dependent hopping rate, (ii) intermittent long range returns via stochastic resetting to a certain location $ \vec{R}_0$ , and (iii) an inspection move where the searcher dynamically updates the resetting position $ \vec{R}_0$ . We compute analytically the capture probability of the target within this strategy and show that it can be maximized by an optimal choice of the control parameters of this strategy. Moreover, the optimal strategy undergoes multiple phase transitions as a function of the control parameters. These phase transitions are generic and occur in all dimensions.
Statistical Mechanics (cond-mat.stat-mech)
5 pages, 7 figures, End Matters and Supplementary material included
Quantum vortex dipole as a probe of the normal component distribution
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-07-09 20:00 EDT
Andrea Barresi, Piotr Magierski, Gabriel Wlazłowski
We investigate the dynamics of quantum vortex dipoles in a strongly interacting, spin-imbalanced Fermi superfluid at zero temperature. Using fully microscopic time-dependent density functional theory, we demonstrate that the dipole trajectory is strongly influenced by the spatial distribution of spin polarization. The resulting forces on the vortices include both longitudinal (dissipative) and transverse components, leading to deflection and shrinking of the dipole during propagation. For moderate polarization, vortex dipoles are deflected and lose energy, while for larger imbalances, they are rapidly annihilated. Our findings provide compelling evidence that spin-imbalanced Fermi gases contain a spatially nonuniform normal component even at zero temperature. We show that vortex dipoles serve as sensitive probes of this component, offering a route to indirectly detect exotic superfluid phases such as the Fulde-Ferrell-Larkin-Ovchinnikov state and related inhomogeneous condensates.
Quantum Gases (cond-mat.quant-gas)
18 pages, 9 figures
Strong acoustic phonon suppression leads to ultralow thermal conductivity and enhanced thermoelectric performance in BaCuGdTe$_3$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Jyoti Duhan, Chris Wolverton, Koushik Pal
Excitations and scatterings among the quantized lattice vibrations, i.e., phonons, govern the lattice thermal conductivity ($ \kappa_l$ ) in crystalline solids. Therefore, effective modulation of $ \kappa_l$ can be achieved through selective manipulation of phonon modes that strongly participate in the heat transport mechanisms. Here, combining accurate first-principles density functional theory calculations and Boltzmann transport theory, we report a layered quaternary chalcogenide semiconductor, BaCuGdTe$ _3$ , which exhibits unusually low $ \kappa_l$ ($ \sim$ 0.14 W/mK at room temperature) despite its ordered crystalline structure. Our analysis reveals that the ultralow $ \kappa_l$ arises mainly from a strong suppression of acoustic phonon modes induced by local distortion, shear vibrations among the layers, and large acoustic-optical avoided-crossing between phonons, which collectively enhances the phonon-scattering rates. Further calculations of the electrical transport properties with explicit consideration of electron-phonon interactions reveal a high thermoelectric figure of merit exceeding unity for this compound at moderate temperature (400-700 K) and carrier concentration $ (1\text{–}5 \times 10^{19}\ \text{cm}^{-3})$ ranges. Our theoretical predictions warrant experimental investigations of the intriguing phonon dynamics, thermal transport mechanisms, and thermoelectric properties in this compound. Moreover, insights from our analysis can be used to design and engineer compounds with ultralow $ \kappa_l$ .
Materials Science (cond-mat.mtrl-sci)
Chiral superconductivity in a semiconducting wire induced by helical magnetic order
New Submission | Superconductivity (cond-mat.supr-con) | 2025-07-09 20:00 EDT
Florinda Viñas Boström, Emil Viñas Boström
Chiral superconductors are sought after for their promising but elusive Majorana zero modes. We show that a one-dimensional semiconductor in proximity to a conventional superconductor and a helical magnet can exhibit chiral superconductivity, without the need for external magnetic fields or intrinsic spin-orbit coupling. The effective proximity-induced gap and the triplet gap arising from magnon fluctuations can be made to interfere constructively. The heterostructure can be tuned into a topological regime with Majorana zero modes at its ends, over a range of chemical potentials proportional to the spin-electron coupling.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 4 figures, 1 page end matter
Detecting Lifshitz Transitions Using Nonlinear Conductivity in Bilayer Graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Tanweer Ahmed, Harsh Varshney, Bao Q. Tu, Kenji Watanabe, Takashi Taniguchi, Marco Gobbi, Fèlix Casanova, Amit Agarwal, Luis E. Hueso
The second-order nonlinear electrical response (NLER) is an intrinsic property of inversion symmetry-broken systems which can provide deep insights into the electronic band structures of atomically thin quantum materials. However, the impact of Fermi surface reconstructions, also known as Lifshitz transitions, on the NLER has remained elusive. We investigated NLER in bilayer graphene (BLG), where the low-energy bands undergo Lifshitz transitions. Here, NLER undergoes a sign change near the Lifshitz transitions even at elevated temperatures $ T\gtrsim10$ K. At the band edge, NLER in BLG is modulated by both extrinsic scattering and interfacial-strain-induced intrinsic Berry curvature dipole, both of which can be finely tuned externally by varying doping and interlayer potential. Away from the band edge, BLG exhibits second-order conductivity exceeding $ 30\mu$ mV$ ^{-1}\Omega^{-1}$ at 3K higher than any previous report. Our work establishes NLER as a reliable tool to probe Lifshitz transitions in quantum materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
This is the pre-peer reviewed version of the following article: Ahmed, T. et al., Small 2025, 21 (21), 2501426, which has been published in final form at this https URL. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions
Small 2025, 21 (21), 2501426
Janus-faced influence of oxygen vacancy in high entropy oxide films with Mott electrons
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Suresh Chandra Joshi, Nandana Bhattacharya, Manav Beniwal, Jyotirmay Maity, Prithwijit Mandal, Hua Zhou, Christoph Klewe, Srimanta Middey
Contrary to traditional approaches, high entropy oxides (HEOs) strategically employ cationic disorder to engineer tunable functionalities. This disorder, stemming from multiple elements at the same crystallographic site, disrupts local symmetry and induces local distortions. By examining a series of single-crystalline [La$ _{0.2}$ Pr$ _{0.2}$ Nd$ _{0.2}$ Sm$ _{0.2}$ Eu$ _{0.2}$ ]NiO$ _{3-\delta}$ thin films, we demonstrate herein that the creation of oxygen vacancies (OVs) further offers a powerful means of tailoring electronic behavior of HEOs by concurrently introducing disorder in the oxygen sublattice and doping electrons into the system. Increasing OV concentration leads to a monotonic increase in room-temperature sheet resistance. A striking feature is the Janus-faced response of the metal-insulator transition (MIT) to OVs due to the interplay among correlation energy scales, electron doping, and disorder. Unlike the monotonous influence of OV observed for the MIT in VO$ _2$ and V$ _2$ O$ _3$ , initial OV doping lowers the MIT temperature here, whereas higher OV levels completely suppress the metallic phase. Magnetotransport measurements further reveal weak localization, strong localization as a function of $ \delta$ . Moreover, the disorder on both $ RE$ and oxygen sublattices is responsible for the Mott-Anderson insulator state. These findings surpass the scope of the recently featured `electron antidoping’ effect and demonstrate the promising opportunity to utilize OV engineering of HEOs for Mottronics and optoelectronics applications.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
17 pages, 5 figures
Excess dissipation shapes symmetry breaking in non-equilibrium currents
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Matteo Sireci, Luca Peliti, Daniel Maria Busiello
Most natural thermodynamic systems operate far from equilibrium, developing persistent currents and organizing into non-equilibrium stationary states (NESSs). Yet, the principles by which such systems self-organize, breaking equilibrium symmetries under external and internal constraints, remain unclear. Here, we establish a general connection between symmetry breaking and dissipation in mesoscopic stochastic systems described by Langevin dynamics. Using a geometric framework based on the inverse diffusion matrix, we decompose the velocity field into excess (gradient) and housekeeping (residual) components. This provides a natural entropy production split: the excess part captures internal reorganization under non-equilibrium conditions, while the housekeeping part quantifies detailed-balance violation due to external forces. We derive an exact equality linking the two, along with an inequality identifying accessible thermodynamics. A weak-noise expansion of the stationary solution reveals the general geometry of the NESS velocity field, enabling a unified classification of steady states. We apply this framework to systems ranging from molecular machines to coupled oscillators, showing how symmetry breaking in trajectory space constrains NESS organization. We further extend our approach to systems with multiplicative noise, deriving how additional symmetry breaking relates to curved (space-dependent) metrics. Finally, we show that both the NESS velocity field and stationary distribution can be derived through variational functionals based on excess dissipation. This work sheds light on the intimate connection between geometric features, dissipative properties, and symmetry breaking, uncovering a classification of NESSs that reflects how emergent organization reflects physical non-equilibrium conditions.
Statistical Mechanics (cond-mat.stat-mech)
Oscillation-Induced Frequency Generation in 1D Quantum Droplets under Harmonic-Gaussian Confinements
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-07-09 20:00 EDT
Jagnyaseni Jogania, Saurab Das, Ajay Nath, Jayanta Bera
We explore the dynamical behavior of one-dimensional quantum droplets (QDs) governed by the extended Gross-Pitaevskii equation, under harmonic confinement supplemented by a static or time-dependent Gaussian spike (Gs) potential. Employing both variational analytical techniques and numerical simulations, we investigate the evolution of the root-mean-square (RMS) size, excitation spectrum, and phase-space dynamics of QDs. Our study reveals that while the harmonic trap sets the primary confinement, the Gs potential enables precise frequency tuning and control over droplet oscillations. A static Gs amplitude modifies the fundamental oscillation frequency depending on its sign, while a time-modulated Gs induces nonlinear dynamics, including higher harmonics and frequency mixing. Our analysis reveals that the resulting frequency spectrum is strongly influenced by inter- and intra-species interactions as well as by the parameters of the external trap. Notably, we establish a relationship between the frequency shift and the amplitude of the Gaussian spike. Wigner phase-space analysis further uncovers coherent rotational behavior, offering insights into hidden phase dynamics not apparent in real-space density profiles.
Quantum Gases (cond-mat.quant-gas)
Design and optimization of in situ self-functionalizing stress sensors
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
Olga Vasiljevic, Nicolas Harmand, Antoine Hubert, Lydia Kebbal, Volker Bormuth, Clara Hayn, Jonathan Fouchard, Marie Anne Breau, Lea-Laetitia Pontani
Mechanical forces are crucial regulators of diverse biological processes, yet their in vivo measurement remains challenging due to limitations of current techniques, that can be destructive or require complex dedicated setups. This study introduces a novel class of biocompatible, self-functionalizing stress sensors based on inverted emulsions, that can be used to measure mechanical stresses inside tissues but can also locally perturb the biological environment through specific binder presentation or drug delivery. We engineered an optimal design for these inverted emulsions, focusing on finding the perfect balance between the two contradictory constraints: achieving low surface tension for deformability while maintaining emulsion instability for efficient self-functionalization and drug release. Proof-of-concept experiments in both agarose gels and complex biological systems, including brain organoids and zebrafish embryos, confirm the droplets ability to deform in response to mechanical stress applied on the tissue, to self-functionalize and to release encapsulated molecules locally. These versatile sensors offer a method for non-invasive stress measurements and targeted chemical delivery within living biological tissues, overcoming current technical barriers in biophysical measurements.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph), Chemical Physics (physics.chem-ph), Tissues and Organs (q-bio.TO)
Evaluating non-equilibrium trajectories via mean back relaxation: Dependence on length and time scales
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Gabriel Knotz, Till M. Muenker, Timo Betz, Matthias Krüger
The mean back relaxation (MBR) relates the value of a stochastic process at three different time points. It has been shown to detect broken detailed balance under certain conditions. For experiments of probe particles in living and passivated cells, MBR was found to be related to the so called effective energy, which quantifies the violation of the fluctuation dissipation theorem. In this manuscript, we discuss the dependence on the length and time parameters that enter MBR, both for cells as well as for a model system, finding qualitative agreement between the two. For the cell data, we extend the phenomenological relation between MBR and effective energy to a larger range of time parameters compared to previous work, allowing to test it in systems with limited resolution. We analyze the variance of back relaxation (VBR) in dependence of the mentioned parameters, relevant for the statistical error in MBR evaluation. For Gaussian systems, the variance is found analytically in terms of the mean squared displacement, and we determine its absolute minimum as a function of the length and time parameters. Comparing VBR from cell data to a Gaussian prediction demonstrates a non-Gaussian process.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
19 pages, 10 figures
Light Induced Half-Metallic Phase in Insulators and Correlated Metals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Suryashekhar Kusari, Arnab Das, H. R. Krishnamurthy, Arti Garg
Non-equilibrium control of electronic properties in condensed matter systems can result in novel phenomena. In this work, we provide a novel non-equilibrium route to realize half-metallic phases. We explore the periodically driven Hubbard model on a bipartite lattice and demonstrate that a periodic drive can transform a weakly interacting metal into a ferrimagnetic half-metal. We consider a Fermi-Hubbard model with only nearest-neighbour hopping and stabilize the elusive phase simply by driving the site potentials periodically. The drive induces staggered second and third-neighbor hopping and a staggered potential between two sublattices in the Floquet Hamiltonian, whose ground state is explored in this work. Close to the dynamical freezing point, due to the suppression of nearest neighbor hopping in the driven system, an effective enhancement of various terms in the Floquet Hamiltonian, including the e-e interactions, occurs. This helps in stabilizing a broad ferrimagnetic half-metallic phase for a wide range of system parameters. The half-metallic phase achieved in the presence of high drive frequency should be stable for exponentially large time scales in drive frequency and could be perpetually stable beyond a strong enough drive amplitude owing to dynamical freezing. It can hence have potential applications in stable spintronics and other upcoming quantum technologies.
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 6 figures
Influence of interphase boundary coherency in high-entropy alloys on their hydrogen storage performance
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
High-entropy alloys (HEAs) have potential for storing hydrogen reversibly at room temperature due to their tunable thermodynamics; however, they usually suffer from the issue of difficult activation. This study shows that while interphase boundaries are effective in activating some HEAs, some other dual-phase HEAs still require extra high-temperature activation. To understand why interphase boundaries are not always effective for activation, microstructural features and hydrogen storage performance of six HEAs with dual phases are compared. Detailed analysis confirms that interphase boundaries are effective for hydrogen absorption without the need for activation treatment, provided that: (i) their fraction is high enough, and (ii) they are not coherent. These findings are discussed in terms of free volume and boundary energy. Coherent interphase boundaries are associated with lower free volume and thus do not act as fast hydrogen diffusion paths. Moreover, the boundary energy of coherent boundaries is lower than incoherent boundaries, making them less favorable sites for heterogeneous hydride nucleation. This research thus suggests that the introduction of incoherent interphase boundaries with a proper fraction is a solution for activating hydrogen storage materials.
Materials Science (cond-mat.mtrl-sci)
Coherent superposition of emitted and resonantly scattered photons from a two-level system driven by an even-$π$ pulse
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
I.V. Krainov, A.I. Galimov, M.V. Rakhlin, A.A. Toropov, T.V. Shubina
We report the observation of a bunching of ~3 photon states, which is a coherent superposition of emitted photons and resonantly scattered laser photons, arising upon excitation by even-$ \pi$ pulses of a two-level system represented by a charged quantum dot in a microcavity. This phenomenon emerges because the exciting laser pulse contains several tens of photons whose quantum amplitude distribution creates such a superposition, and the polarization of the scattered photons is changed by the interaction with the charged resonant system. Such a beam is a high-order member of the Fock space, promising for quantum technologies.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
4 pages, 2 figures
A simpler probe of the quantum Mpemba effect in closed systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Filiberto Ares, Colin Rylands, Pasquale Calabrese
We study the local relaxation of closed quantum systems through the relative entropy between the reduced density matrix and its long time limit. We show, using analytic arguments combined with numerical checks, that this relative entropy can be very well approximated by an entropy difference, affording a significant computational advantage. We go on to relate this to the entanglement asymmetry of the subsystem with respect to time translation invariance. In doing this, we obtain a simple probe of the relaxation dynamics of closed many-body systems and use it to re-examine the quantum Mpemba effect, wherein states can relax faster if they are initially further from equilibrium. We reproduce earlier instances of the effect related to symmetry restoration as well as uncover new cases in the absence of such symmetries. For integrable models, we obtain the criteria for this to occur using the quasiparticle picture. Lastly, we show that, in models obeying the entanglement membrane picture, the quantum Mpemba effect cannot occur for a large class of initial states.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
17 pages, 3 figures
A Hydrodynamic Theory for Non-Equilibrium Full Counting Statistics in One-Dimensional Quantum Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
David X. Horvath, Benjamin Doyon, Paola Ruggiero
We study the dynamics of charge fluctuations after homogeneous quantum quenches in one-dimensional systems with ballistic transport. For short but macroscopic times where the non-trivial dynamics is largely dominated by long-range correlations, a simple expression for the associated full counting statistics can be obtained by hydrodynamic arguments. This formula links the non-equilibrium charge fluctuation after the quench to the fluctuations of the associated current after a charge-biased inhomogeneous modification of the original quench which corresponds to the paradigmatic partitioning protocol. Under certain assumptions, the fluctuations in the latter case can be expressed by explicit closed form formulas in terms of thermodynamic and hydrodynamic quantities via the Ballistic Fluctuations Theory. In this work, we identify precise physical conditions for the applicability of a fully hydrodynamic theory, and provide a detailed analysis explicitly demonstrating how such conditions are met and how this leads to such hydrodynamic treatment. We discuss these conditions at length in non-relativistic free fermions, where calculations become feasible and allow for cross-checks against exact results. In physically relevant cases, strong long-range correlations can complicate the hydrodynamic picture, but our formula still correctly reproduces the first cumulants.
Statistical Mechanics (cond-mat.stat-mech), Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
52+28 pages, 1 figure
Statistical properties of stochastic functionals under general resetting
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
We derive the characteristic function of stochastic functionals of a random walk whose position is reset to the origin at random times drawn from a general probability distribution. We analyze the long-time behavior and obtain the temporal scaling of the first two moments of any stochastic functional of the random walk when the resetting time distribution exhibits a power-law tail. When the resetting times PDF has finite moments, the probability density of any functional converges to a delta function centered at its mean, indicating an ergodic phase. We explicitly examine the case of the half-occupation time and derive the ergodicity breaking parameter, the first two moments, and the limiting distribution when the resetting time distribution follows a power-law tail, for both Brownian and subdiffusive random walks. We characterize the three different shapes of the limiting distribution as a function of the exponent of the resetting distribution. Our theoretical findings are supported by Monte Carlo simulations, which show excellent agreement with the analytical results.
Statistical Mechanics (cond-mat.stat-mech)
Chladni states in Ising Spin Lattices
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Giulio Iannelli, Pablo Villegas
Spontaneous symmetry breaking is the core concept for understanding the emergence of collective order. In finite-dimensional systems, however, the nature of the broken phase is often constrained by the compatibility between spontaneous order and the microscopic symmetries of the underlying lattice. Here, we propose the topological substratum on which Ising spin lattices exhibit long-range order when cooled under non-ergodic conditions. Our topological decomposition, tantamount to resonating sand plates, enables monitoring and control of the dynamical evolution in systems surfing complex energy landscapes with multiple metastable patterns.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Physics and Society (physics.soc-ph)
5 pages, 3 figures and Supplemental Material
Second-Order Conductivity Probes a Cascade of Singularities in a Moiré Superlattice
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Tanweer Ahmed, Bao Q. Tu, Kenji Watanabe, Takashi Taniguchi, Marco Gobbi, Fèlix Casanova, Luis E. Hueso
Systems lacking inversion symmetry inherently demonstrate a nonlinear electrical response (NLER) to an applied electric bias, emerging through extrinsic mechanisms. This response is highly sensitive to the electronic band structure, which can be engineered with remarkable precision in moiré superlattices formed from atomically thin quantum materials. Moiré superlattices host complex Fermi surface reconstructions near van Hove singularities (vHSs) in the electronic density of states. However, the role of these reconstructions in shaping NLER remains insufficiently understood. In this work, we systematically explore NLER in moiré superlattices of twisted double bilayer graphene (tDBLG) by tuning the Fermi level across multiple moiré bands on both sides of the charge neutrality point. We observe sharp variations and sign reversals in the NLER appearing via extrinsic pathways near mid-band vHSs. The second-order conductivity close to the vHSs demonstrates a much higher value than previous reports of extrinsic NLER in any other material. Our results demonstrate that NLER can serve as a sensitive probe of Fermi surface reconstructions and establish tDBLG as a versatile and highly efficient platform for generating and controlling the nonlinear electrical response.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
This is the pre-peer reviewed version, which has been published in final form in ACS Nano. The published article and the supporting information can be obtained from this https URL. This article may be used for non-commercial purposes
Generating single- and many-body quantum magnonic states
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Violet Williams, Jayakrishnan M. P. Nair, Yaroslav Tserkovnyak, Benedetta Flebus
The growing interest in quantum magnonics is driving the development of advanced techniques for generating, controlling, and detecting non-classical magnonic states. Here, we explore the potential of an ensemble of solid-state spin defects coupled to a shared magnetic bath as a source of such states. We establish a theoretical framework to characterize the quantum correlations among magnons emitted by the ensemble into the bath and investigate how these correlations depend on experimentally tunable parameters. Our findings show that the emitted magnons retain the quantum correlations inherent to the solid-state emitters, paving the way for the deterministic generation of quantum many-body magnonic states.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Static treatment of dynamic interactions in correlated electron systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Anton Pauli, Akshat Mishra, Malte Rösner, Erik G.C.P. van Loon
Correlated electron physics is intrinsically a multiscale problem, since high-energy electronic states screen the interactions between the correlated electrons close to the Fermi level, thereby reducing the magnitude of the interaction strength and dramatically shortening its range. Thus, the handling of screening is an essential ingredient in the first-principles modelling of correlated electron systems. Screening is an intrinsically dynamic process and the corresponding downfolding methods such as the constrained Random Phase Approximation indeed produce a dynamic interaction. However, many low-energy methods require an instantaneous interaction as input, which makes it necessary to map the fully dynamic interaction to an effective instantaneous interaction strength. It is a priori not clear if and when such an effective model can capture the physics of the one with dynamic interaction and how to best perform the mapping. Here, we provide a systematic benchmark relevant to correlated materials, in the form of the Anderson impurity model. Overall, we find that a moment-based approach recently proposed by Scott and Booth performs well. We also identify physical regimes, especially under doping, where an instantaneous interaction cannot capture all of the relevant physics.
Strongly Correlated Electrons (cond-mat.str-el)
Fractional Brownian Motion with Negative Hurst Exponent
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Baruch Meerson, Pavel V. Sasorov
Fractional Brownian motion (fBm) is an important scale-invariant Gaussian non-Markovian process with stationary increments, which serves as a prototypical example of a system with long-range temporal correlations and anomalous diffusion. The fBm is traditionally defined for the Hurst exponent $ H$ in the range $ -1/2<H<0$ . Here we extend this definition to the strongly anti-persistent regime $ -1/2<H<0$ . The extended fBm is not a pointwise process, so we regularize it via a local temporal averaging with a narrow filter. The extended fBm turns out to be stationary, and we derive its autocorrelation function. The stationarity implies a complete arrest of diffusion in this region of $ H$ . We also determine the variance of a closely related Gaussian process: the stationary fractional Ornstein–Uhlenbeck (fOU) process, extended to the range $ -1/2<H<0$ and smoothed in the same way as the fBm. Remarkably, the smoothed fOU process turns out to be insensitive to the strength of the confining potential. Finally, we determine the optimal paths of the conditioned fBm and fOU processes for $ -1/2<H<0$ . In the marginal case $ H=0$ , our results match continuously with known results for the traditionally defined fBm and fOU processes.
Statistical Mechanics (cond-mat.stat-mech), Probability (math.PR)
10 pages, 6 figures
Finite-size scaling of percolation on scale-free networks
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Xuewei Zhao, Liwenying Yang, Dan Peng, Run-Ran Liu, Ming Li
Critical phenomena on scale-free networks with a degree distribution $ p_k \sim k^{-\lambda}$ exhibit rich finite-size effects due to its structural heterogeneity. We systematically study the finite-size scaling of percolation and identify two distinct crossover routes to mean-field behavior: one controlled by the degree exponent $ \lambda$ , the other by the degree cutoff $ K \sim V^{\kappa}$ , where $ V$ is the system size and $ \kappa \in [0,1]$ is the cutoff exponent. Increasing $ \lambda$ or decreasing $ \kappa$ suppresses heterogeneity and drives the system toward mean-field behavior, with logarithmic corrections near the marginal case. These findings provide a unified picture of the crossover from heterogeneous to homogeneous criticality. In the crossover regime, we observe rich finite-size phenomena, including the transition from vanishing to divergent susceptibility, distinct exponents for the shift and fluctuation of pseudocritical points, and a numerical clarification of previous theoretical debates.
Statistical Mechanics (cond-mat.stat-mech)
10 pages, 9 figures
Cluster-diagrammatic D-TRILEX approach to non-local electronic correlations
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
Félix Fossati, Evgeny A. Stepanov
In this work, we extend the theoretical approach known as “D-TRILEX”, developed for solving correlated electronic systems, to a cluster reference system for the diagrammatic expansion. This framework allows us to consistently combine the exact treatment of short-range correlation effects within the cluster, with an efficient diagrammatic description of the long-range charge and spin collective fluctuations beyond the cluster. We demonstrate the effectiveness of our approach by applying it to the one-dimensional nano-ring Hubbard model, where the low dimensionality enhances non-local correlations. Our results show that the cluster extension of D-TRILEX accurately reproduces the electronic self-energy at momenta corresponding to the Fermi energy, in good agreement with the numerically exact quantum Monte Carlo solution of the problem, and outperforms significantly more computationally demanding approach based on the parquet approximation. We show that the D-TRILEX diagrammatic extension drastically reduces the periodization ambiguity of cluster quantities when mapping back to the original lattice, compared to cluster dynamical mean-field theory (CDMFT). Furthermore, we identify the CDMFT impurity problem as the main source of the translational-symmetry breaking and propose the computational scheme for improving the starting point for the cluster-diagrammatic expansion.
Strongly Correlated Electrons (cond-mat.str-el)
Liquid-Gas Criticality of Hyperuniform Fluids
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Shang Gao, Hao Shang, Hao Hu, Yu-Qiang Ma, Qun-Li Lei
In statistical physics, a well-accepted knowledge is that liquid-gas (LG) phase transition with diverging critical fluctuations lies in the universality class of Ising model. Yet, whether non-equilibrium effect alone can alter this conclusion remains an open question. Here, we study the LG criticality of a hyperuniform (HU) fluid composed of active spinners, where phase separation is induced by dissipative collisions. Strikingly, at the LG critical point, the HU fluid exhibits normal Gaussian density fluctuations instead of the diverging fluctuations. Through hydrodynamic field theory and renormalization-group analysis, we demonstrate that hyperuniformity reduces the upper critical dimension from d_c = 4 (classical fluids) to d_c = 2 due to an emerging long-range correlation induced by center-of-mass conservation. Large-scale stochastic field simulations confirm this dimensional reduction, and reveal diverging response function along with anomalous zero-range correlation function at the critical point, indicating the absence of an effective fluctuation-dissipation relationship in the system. The simulation also identifies anomalous finite-size scaling in density fluctuation, energy fluctuation, and Binder cumulant. Furthermore, HU fluid also exihibits non-classical spinodal decomposition dynamics with diverging decomposition time but non-diverging decomposition length scale. Our results provide an exception to the classical paradigms of LG critical phenomena and highlight how non-equilibrium effect can reshape universality classes of classical phase transitions.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
26 pages, 11 figures
Spin properties in droplet epitaxy-grown telecom quantum dots
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Marius Cizauskas, Elisa M. Sala, Jon Heffernan, A. Mark Fox, Manfred Bayer, Alex Greilich
We investigate the spin properties of InAs/InGaAs/InP quantum dots grown by metalorganic vapor-phase epitaxy (MOVPE) deposition using droplet epitaxy, which emit in the telecom C-band. Using pump-probe Faraday ellipticity measurements, we determine electron and hole $ g$ -factors of $ |g_e| = 0.934$ and $ |g_h| = 0.471$ , with the electron $ g$ -factor being nearly twice as low as typical molecular beam epitaxy Stranski-Krastanov (SK) grown samples. Most significantly, we measure a longitudinal spin relaxation time $ T_1 = 2.95,\mu s$ , representing an order of magnitude improvement over comparable MBE SK grown samples. Despite significant electron $ g$ -factor anisotropy, we observed that it is reduced relative to similar material composition samples grown with MBE or MOVPE SK methods. We attribute these g-factor anisotropy and spin lifetime improvements to the enhanced structural symmetry achieved via MOVPE droplet epitaxy, which mitigates the inherent structural asymmetry in strain-driven growth approaches for InAs/InP quantum dots. These results demonstrate that MOVPE droplet epitaxy-grown InAs/InGaAs/InP quantum dots exhibit favorable spin properties for potential implementation in quantum information applications.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
New universality classes govern the critical and multicritical behavior of an active Ising model
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
The Ising model is one of the most well known models in statistical physics, with its critical behavior governed by the Wilson-Fisher universality class (UC). When active motility is incorporated into the Ising model by, e.g., dictating that the spins’ directional movements follow their orientations, the spin number density necessarily constitutes a soft mode in the hydrodynamic description, and can therefore modify the scaling behavior of the system. Here, we show that this is indeed the case in a critical active Ising model in which density can impede the system’s collective motion. Specifically, we use a perturbative dynamic renormalization group method to the one-loop level to uncover three new UCs, one of which supersedes the Wilson-Fisher UC to become the generic UC that governs the critical behavior of the active Ising model.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
Main text: 5 pages, 2 figures; Supplemental Material: 29 pages
Irreversibility in scalar active turbulence: The role of topological defects
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-07-09 20:00 EDT
Byjesh N. Radhakrishnan, Francesco Serafin, Thomas L. Schmidt, Etienne Fodor
In many active systems, swimmers collectively stir the surrounding fluid to stabilize some self-sustained vortices. The resulting nonequilibrium state is often referred to as active turbulence, by analogy with the turbulence of passive fluids under external stirring. Although active turbulence clearly operates far from equilibrium, it can be challenging to pinpoint which emergent features primarily control the deviation from an equilibrium reversible dynamics. Here, we reveal that dynamical irreversibility essentially stems from singularities in the active stress. Specifically, considering the coupled dynamics of the swimmer density and the stream function, we demonstrate that the symmetries of vortical flows around defects determine the overall irreversibility. Our detailed analysis leads to identifying specific configurations of defect pairs as the dominant contribution to irreversibility.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft), Fluid Dynamics (physics.flu-dyn)
25 pages, 8 figures
Dynamical and structural properties of an absorbing phase transition: a case study from granular systems
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
Raphael Maire, Andrea Plati, Frank Smallenburg, Giuseppe Foffi
We investigate the dynamical and structural properties of absorbing phase transitions (APTs) within granular systems. Specifically, we examine a model for vibrofluidized systems of spherical grains, which transition from a state of pure vertical motion to a horizontal diffusive state upon increased density. Depending on the details of the system, we observe both continuous and discontinuous transitions in numerical simulations. We explain this using a theoretical analysis based on kinetic theory applied to a coarse-grained model, which elucidates the role of a synchronization effect in determining the nature of the transition. A fluctuating hydrodynamic theory, which quantitatively describes the structural and dynamical properties of the active state such as hyperuniformity is derived from the microscopic dynamics, together with an equilibrium-like assumption concerning the noises on the hydrodynamic fields. This work expands on previous studies by providing a comprehensive examination of the APT characteristics and proposing new theoretical models to interpret the observed behaviors.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
Model of luminescence and delayed luminescence correlated blinking in single CsPbBr$_3$ nanocrystals
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Eduard A. Podshivaylov, Alexander M. Shekhin, Maria A. Kniazeva, Alexander O. Tarasevich, Elizaveta V. Sapozhnikova, Anatoly P. Pushkarev, Ivan Yu. Eremchev, Andrei V. Naumov, Pavel A. Frantsuzov
Cesium lead halide nanocrystals and quantum dots are prominent materials for different types of applications because of their remarkable photophysical properties. However, they are also known to exhibit the same effects observed for non-perovskite colloidal semiconductor quantum dots such as blinking, photobleaching, delayed luminescence, etc. In this study we reveal the correlations between fast and delayed emission components for both the intensity and characteristic decay time for single CsPbBr$ _3$ nanocrystals. In order to explain the phenomena observed, we propose a novel model of single CsPbBr$ _3$ nanocrystals luminescence blinking based on the hypothesis of slow variations in the electron-phonon coupling.
Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech)
Reference compositions for bismuth telluride thermoelectric materials for low-temperature power generation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-07-09 20:00 EDT
Nirma Kumari, Jaywan Chung, Seunghyun Oh, Jeongin Jang, Jongho Park, Ji Hui Son, SuDong Park, Byungki Ryu
Thermoelectric (TE) technology enables direct heat-to-electricity conversion and is gaining attention as a clean, fuel-saving, and carbon-neutral solution for industrial, automotive, and marine applications. Despite nearly a century of research, apart from successes in deep-space power sources and solid-state cooling modules, the industrialization and commercialization of TE power generation remain limited. Since the new millennium, nanostructured bulk materials have accelerated the discovery of new TE systems. However, due to limited access to high-temperature heat sources, energy harvesting still relies almost exclusively on BiTe-based alloys, which are the only system operating stably near room temperature. Although many BiTe-based compositions have been proposed, concerns over reproducibility, reliability, and lifetime continue to hinder industrial adoption. Here, we aim to develop reference BiTe-based thermoelectric materials through data-driven analysis of Starrydata2, the world’s largest thermoelectric database. We identify Bi0.46Sb1.54Te3 and Bi2Te2.7Se0.3 as the most frequently studied ternary compositions. These were synthesized using hot pressing and spark-plasma sintering. Thermoelectric properties were evaluated with respect to the processing method and measurement direction. The results align closely with the median of reported data, confirming the representativeness of the selected compositions. We propose these as reference BiTe materials, accompanied by transparent data and validated benchmarks. Their use can support the standardization of TE legs and modules while accelerating performance evaluation and industrial integration. We further estimated the performance of a thermoelectric module made from the reference composition, which gives the power output of over 2.51 W and an efficiency of 3.58% at a temperature difference of 120 K.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
45 pages, 4 tables, 14 figures
A Comprehensive MARTINI Coarse-Grained Framework for Phyllosilicate Clay/Polymer Nanocomposites: From Atomistic Validation to Mesoscale Insights
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
Phyllosilicate clays have diverse applications in packaging industries and are found highly suitable for formulation, including thermoplastic starch (TPS), polyethylene (PE), or their combination. We developed CG MARTINI-3 parameters of the pyrophyllite using Lifshitz theory and experimental surface tension data. These initial bead assignments of pyrophyllite and periodic tetramethylammonium-montmorillonite (TMA-MMT) sheet were fine-tuned using optimal reproduction of structural, thermodynamic, and dynamic properties obtained via all-atom (AA) simulation of TPS with a periodic pyrophyllite sheet. These developed models predicted the correct AA radial distribution function and two-body excess entropy for polymer-sorbitol pairs, showcasing the robustness of the developed CG model in predicting the properties not used in parameterization. These composite simulations revealed acceleration (for pyrophyllite) or retardation (for TMA-MMT) of khun segment dynamics (compared to melt) with the depletion of polymer near the surface. The developed CG parameters were used to investigate the long-time behavior of TPS-polyethylene (PE) melt and their Cloisite-15A-based composite systems. The coordination number indicated compatibilization of the TPS-PE phase, achieved by binding TPS through its bare polar surface and PE via alkyl-mediated interactions, which consequently reduced the TPS-PE interfacial surface tension from 45 mN/m to 13.06 mN/m. Additionally, high TPS-clay coordination, sustained localization of clay at the TPS-PE interface, and clay aggregation observed in CG simulation closely agree with experimental observations. Further, the CG model effectively captured the clay-mediated variation in the overall morphology of the TPS-PE system and their direct impact on chain conformational properties, making this CG model highly suitable for a material design perspective.
Soft Condensed Matter (cond-mat.soft)
“Ideal” Topological Heavy Fermion Model in Two-dimensional Moiré Heterostructures with Type-II Band Alignment
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-07-09 20:00 EDT
Yunzhe Liu, Anoj Aryal, Dumitru Calugaru, Zhenyao Fang, Kaijie Yang, Haoyu Hu, Qimin Yan, B. Andrei Bernevig, Chao-xing Liu
Topological flat bands play an essential role in inducing exotic interacting physics, ranging from fractional Chern insulators to superconductivity, in moiré materials. When topological flat bands possess concentrated quantum geometry, a topological heavy fermion (THF) model was proposed as the starting point to describe the interacting moiré physics. In this work, we propose a design principle for realizing “ideal” THF model, which can host an exact flat band with “ideal quantum geometry”, namely the trace of Fubini-Study metric equals to the Berry curvature, in a class of two-dimensional moiré heterostructures with type-II band alignment. We first introduce a moiré Chern-band model to describe this system and show that topological flat bands can be realized in this model when the moiré superlattice potential is stronger than the type-II atomic band gap of the heterostructure. Next, we map this model into a THF model that consists of a localized orbital for “f-electron” and a conducting band for “c-electron”. We find that both the flatness and quantum geometry of the mini-bands in this THF model depend on the energy gap between c-electron and f-electron bands at $ \Gamma$ which is experimentally controllable via external gate voltages. This tunability will allow us to realize an “ideal” topological flat band with zero band-width and “ideal quantum geometry” in this THF model. Our design strategy of topological flat bands is insensitive of twist angle. We also discuss possible material candidates for moiré heterostructures with type-II band alignment.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Bridging Machine Learning and Glassy Dynamics Theory for Predictive Polymer Modeling
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-07-09 20:00 EDT
Anh D. Phan, Ngo T. Que, Nguyen T. T. Duyen, Phan Thanh Viet, Quach K. Quang, Baicheng Mei
Understanding and predicting the glassy dynamics of polymers remain fundamental challenges in soft matter physics. While the Elastically Collective Nonlinear Langevin Equation (ECNLE) theory has been successful in describing relaxation dynamics, its practical application to polymers depends on a thermal mapping to connect theory with experiment, which in turn requires detailed thermodynamic data. Such data may not be available for chemically complex or newly designed polymers. In this work, we propose a simple approach that integrates machine learning-predicted glass transition temperatures (Tg) with a simplified thermal mapping based on an effective thermal expansion coefficient to overcome these limitations. This approach can provide quantitatively accurate predictions of relaxation dynamics across a broad range of polymers. Rather than replacing the original thermal mapping, our method complements it by trading formal rigor for computational efficiency and broader applicability in high-throughput screening and materials with limited available data. Moreover, we introduce a physically motivated modification to the thermal mapping that resolves discrepancies in the description of low-Tg polymers. Our results establish a generalizable approach for predictive modeling of glassy polymer dynamics and point toward new directions for theory-guided materials discovery.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech), Chemical Physics (physics.chem-ph), Computational Physics (physics.comp-ph)
12 pages, 7 figures, accepted for publication in Journal of Applied Physics
Ontological differentiation as a measure of semantic accuracy
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-07-09 20:00 EDT
Pablo Garcia-Cuadrillero, Fabio Revuelta, Jose Angel Capitan
Understanding semantic relationships within complex networks derived from lexical resources is fundamental for network science and language modeling. While network embedding methods capture contextual similarity, quantifying semantic distance based directly on explicit definitional structure remains challenging. Accurate measures of semantic similarity allow for navigation on lexical networks based on maximizing semantic similarity in each navigation jump (Semantic Navigation, SN). This work introduces Ontological Differentiation (OD), a formal method for measuring divergence between concepts by analyzing overlap during recursive definition expansion. The methodology is applied to networks extracted from the Simple English Wiktionary, comparing OD scores with other measures of semantic similarity proposed in the literature (cosine similarity based on random-walk network exploration). We find weak correlations between direct pairwise OD scores and cosine similarities across $ \sim$ ~2 million word pairs, sampled from a pool representing over 50% of the entries in the Wiktionary lexicon. This establishes OD as a largely independent, definition-based semantic metric, whose orthogonality to cosine similarity becomes more pronounced when low-semantic-content terms were removed from the dataset. Additionally, we use cumulative OD scores to evaluate paths generated by vector-based SN and structurally optimal Shortest Paths (SP) across networks. We find SN paths consistently exhibit significantly lower cumulative OD scores than shortest paths, suggesting that SN produces trajectories more coherent with the dictionary’s definitional structure, as measured by OD. Ontological Differentiation thus provides a novel, definition-grounded tool for analyzing semantic structure and validating navigation processes in lexical networks.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
15 pages with 4 figures + 10 pages supplemental material with 5 figures, so 25 pages 9 figures total
Harmonic emission as a probe to coherent transitions in the topological superconductors
New Submission | Other Condensed Matter (cond-mat.other) | 2025-07-09 20:00 EDT
Nivash R., S. Srinidhi, Jayendra N. Bandyopadhyay, Amol R. Holkundkar
We investigate the dynamical behavior of a topological superconducting system, demonstrating that its static configuration undergoes a transition driven by an intrinsic supercurrent. By analyzing the band population, we confirm the quasiparticle nature of the system both in the presence and absence of an external laser field. Under laser driving, we observe an enhancement in static emission forming a plateau-like structure, accompanied by multiple coherent transitions in the population. These transitions exhibit Rabi-like oscillations, attributed to the presence of Majorana bound states (MBS), further reinforcing the quasiparticle character of the model. Our results highlight the efficacy of laser driving as a probe of the system’s topological and dynamical stability.
Other Condensed Matter (cond-mat.other), Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
10 pages, main paper and supplementary information, Communicated
Topological Holography for Mixed-State Phases and Phase Transitions
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-07-09 20:00 EDT
We extend the symmetry topological field theory (SymTFT) framework to open quantum systems. Using canonical purification, we embed mixed states into a doubled (2+1)-dimensional topological order and employ the slab construction to study (1+1)-dimensional mixed-state phases through condensable algebras in the doubled SymTFT. Hermiticity and positivity of the density matrix impose additional constraints on allowable anyon condensations, enabling a systematic classification of mixed-state phases - including strong-to-weak symmetry breaking (SWSSB) and average symmetry-protected topological (ASPT) phases. We present examples of mixed-state phase transitions involving SWSSB and show how gauging within the open SymTFT framework reveals connections among different mixed-state phases.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
22 pages, 7 figures, and appendix