CMP Journal 2025-04-16
Statistics
Nature: 26
Nature Nanotechnology: 1
Physical Review Letters: 17
Physical Review X: 2
arXiv: 68
Nature
Mitochondrial metabolism sustains DNMT3A-R882-mutant clonal haematopoiesis
Original Paper | Cancer stem cells | 2025-04-15 20:00 EDT
Malgorzata Gozdecka, Monika Dudek, Sean Wen, Muxin Gu, Richard J. Stopforth, Justyna Rak, Aristi Damaskou, Guinevere L. Grice, Matthew A. McLoughlin, Laura Bond, Rachael Wilson, George Giotopoulos, Vijaya Mahalingam Shanmugiah, Rula Bany Bakar, Eliza Yankova, Jonathan L. Cooper, Nisha Narayan, Sarah J. Horton, Ryan Asby, Dean C. Pask, Annalisa Mupo, Graham Duddy, Ludovica Marando, Theodoros Georgomanolis, Paul Carter, Amirtha Priya Ramesh, William G. Dunn, Clea Barcena, Paolo Gallipoli, Kosuke Yusa, Slavé Petrovski, Penny Wright, Pedro M. Quiros, Christian Frezza, James A. Nathan, Arthur Kaser, Siddhartha Kar, Konstantinos Tzelepis, Jonathan Mitchell, Margarete A. Fabre, Brian J. P. Huntly, George S. Vassiliou
Somatic DNMT3A R882 codon mutations drive the most common form of clonal haematopoiesis (CH) and are associated with increased acute myeloid leukaemia (AML) risk1,2. Preventing expansion of DNMT3A-R882-mutant haematopoietic stem/progenitor cells (HSPCs) may therefore avert progression to AML. To identify DNMT3A-R882-mutant-specific vulnerabilities, we conducted a genome-wide CRISPR screen on primary mouse Dnmt3aR882H/+ HSPCs. Amongst the 640 vulnerability genes identified, many were involved in mitochondrial metabolism and metabolic flux analysis confirmed enhanced oxidative phosphorylation usage in Dnmt3aR882H/+ vs Dnmt3a+/+ (WT) HSPCs. We selected citrate/malate transporter Slc25a1 and complex I component Ndufb11, for which pharmacological inhibitors are available, for downstream studies. In vivo administration of SLC25A1 inhibitor CTPI2 and complex I inhibitors IACS-010759 and metformin, suppressed post-transplantation clonal expansion of Dnmt3aR882H/+, but not WT, LT-HSC. The effect of metformin was recapitulated using a primary human DNMT3A-R882 CH sample. Notably, analysis of 412,234 UK Biobank (UKB) participants revealed that individuals taking metformin had markedly lower prevalence of DNMT3A-R882-mutant CH, after controlling for potential confounders including glycated haemoglobin, diabetes and body mass index. Collectively, our data propose modulation of mitochondrial metabolism as a therapeutic strategy for prevention of DNMT3A-R882-mutant AML.
Cancer stem cells, Haematopoietic stem cells
The phased pan-genome of tetraploid European potato
Original Paper | Agricultural genetics | 2025-04-15 20:00 EDT
Hequan Sun, Sergio Tusso, Craig I. Dent, Manish Goel, Raúl Y. Wijfjes, Lisa C. Baus, Xiao Dong, José A. Campoy, Ana Kurdadze, Birgit Walkemeier, Christine Sänger, Bruno Huettel, Ronald C. B. Hutten, Herman J. van Eck, Klaus J. Dehmer, Korbinian Schneeberger
Potatoes were first brought to Europe in the sixteenth century1,2. Two hundred years later, one of the species had become one of the most important food sources across the entire continent and, later, even the entire world3. However, its highly heterozygous, autotetraploid genome has complicated its improvement since then4,5,6,7. Here we present the pan-genome of European potatoes generated from phased genome assemblies of ten historical potato cultivars, which includes approximately 85% of all haplotypes segregating in Europe. Sequence diversity between the haplotypes was extremely high (for example, 20× higher than in humans), owing to numerous introgressions from wild potato species. By contrast, haplotype diversity was very low, in agreement with the population bottlenecks caused by domestication and transition to Europe. To illustrate a practical application of the pan-genome, we converted it into a haplotype graph and used it to generate phased, megabase-scale pseudo-genome assemblies of commercial potatoes (including the famous French fries potato ‘Russet Burbank’) using cost-efficient short reads only. In summary, we present a nearly complete pan-genome of autotetraploid European potato, we describe extraordinarily high sequence diversity in a domesticated crop, and we outline how this resource might be used to accelerate genomics-assisted breeding and research.
Agricultural genetics, Genetic variation, Genome informatics, Haplotypes, Plant genetics
Metformin reduces the competitive advantage of Dnmt3aR878H HSPCs
Original Paper | Cancer stem cells | 2025-04-15 20:00 EDT
Mohsen Hosseini, Veronique Voisin, Ali Chegini, Angelica Varesi, Severine Cathelin, Dhanoop Manikoth Ayyathan, Alex C. H. Liu, Yitong Yang, Vivian Wang, Abdula Maher, Eric Grignano, Julie A. Reisz, Angelo D’Alessandro, Kira Young, Yiyan Wu, Martina Fiumara, Samuele Ferrari, Luigi Naldini, Federico Gaiti, Shraddha Pai, Grace Egan, Aaron D. Schimmer, Gary D. Bader, John E. Dick, Stephanie Z. Xie, Jennifer J. Trowbridge, Steven M. Chan
Clonal haematopoiesis arises when a haematopoietic stem cell (HSC) acquires a mutation that confers a competitive advantage over wild-type HSCs, resulting in its clonal expansion. Individuals with clonal haematopoiesis are at increased risk of developing haematologic neoplasms and other age-related inflammatory illnesses1,2,3,4. Suppressing the expansion of mutant HSCs may prevent these outcomes; however, such interventions have not yet been identified. The most common clonal haematopoiesis driver mutations are in the DNMT3A gene, with arginine 882 (R882) being a mutation hotspot1,2,3,5,6,7. Here we show that mouse haematopoietic stem and progenitor cells (HSPCs) carrying the Dnmt3aR878H/+ mutation, equivalent to human DNMT3AR882H/+, have increased mitochondrial respiration compared with wild-type cells and are dependent on this metabolic reprogramming for their competitive advantage. Treatment with metformin, an anti-diabetic drug that inhibits mitochondrial respiration8, reduced the competitive advantage of Dnmt3aR878H/+ HSCs. Through a multi-omics approach, we found that metformin acts by enhancing methylation potential in Dnmt3aR878H/+ HSPCs and reversing the aberrant DNA CpG methylation and histone H3 K27 trimethylation profiles in these cells. Metformin also reduced the competitive advantage of human DNMT3AR882H HSPCs generated by prime editing. Our findings provide preclinical rationale for investigating metformin as a preventive intervention against DNMT3A R882 mutation-driven clonal haematopoiesis in humans.
Cancer stem cells, Haematopoietic stem cells, Leukaemia
Electric-field-induced domain walls in wurtzite ferroelectrics
Original Paper | Electrical and electronic engineering | 2025-04-15 20:00 EDT
Ding Wang, Danhao Wang, Mahlet Molla, Yujie Liu, Samuel Yang, Shuaishuai Yuan, Jiangnan Liu, Mingtao Hu, Yuanpeng Wu, Tao Ma, Kai Sun, Hong Guo, Emmanouil Kioupakis, Zetian Mi
Wurtzite ferroelectrics have transformative potential for next-generation microelectronics. A comprehensive understanding of their ferroelectric properties and domain energetics is crucial for tailoring their ferroelectric characteristics and exploiting their functional properties in practical devices. Despite burgeoning interest, the exact configurations and electronic structures of domain walls in wurtzite ferroelectrics remain elusive. Here we explain the atomic configurations and electronic properties of electric-field-induced domain walls in ferroelectric ScGaN. By combining transmission electron microscopy and theoretical calculations, a charged domain wall with a buckled two-dimensional hexagonal phase is revealed. Density functional theory calculations confirm that such domain-wall structures further give rise to unprecedented mid-gap states within the forbidden band. Quantitative analysis unveils a universal charge-compensation mechanism stabilizing antipolar domain walls in ferroelectric materials, in which the polarization discontinuity at the 180° domain wall is compensated by the unbonded valence electrons. Furthermore, the reconfigurable conductivity of these domain walls is experimentally demonstrated, showcasing their potential for ultrascaled device applications.
Electrical and electronic engineering, Electronic devices, Information storage
Multi-zonal liver organoids from human pluripotent stem cells
Original Paper | Regenerative medicine | 2025-04-15 20:00 EDT
Hasan Al Reza, Connie Santangelo, Kentaro Iwasawa, Abid Al Reza, Sachiko Sekiya, Kathryn Glaser, Alexander Bondoc, Jonathan Merola, Takanori Takebe
Distinct hepatocyte subpopulations are spatially segregated along the portal-central axis and are critical to understanding metabolic homeostasis and injury in the liver1. Although several bioactive molecules, including ascorbate and bilirubin, have been described as having a role in directing zonal fates, zonal liver architecture has not yet been replicated in vitro2,3. Here, to evaluate hepatic zonal polarity, we developed a self-assembling zone-specific liver organoid by co-culturing ascorbate- and bilirubin-enriched hepatic progenitors derived from human induced pluripotent stem cells. We found that preconditioned hepatocyte-like cells exhibited zone-specific functions associated with the urea cycle, glutathione synthesis and glutamate synthesis. Single-nucleus RNA-sequencing analysis of these zonally patterned organoids identifies a hepatoblast differentiation trajectory that dictates periportal, interzonal and pericentral human hepatocytes. Epigenetic and transcriptomic analysis showed that zonal identity is orchestrated by ascorbate- or bilirubin-dependent binding of EP300 to TET1 or HIF1α. Transplantation of the self-assembled zonally patterned human organoids improved survival of immunodeficient rats who underwent bile duct ligation by ameliorating the hyperammonaemia and hyperbilirubinaemia. Overall, this multi-zonal organoid system serves as an in vitro human model to better recapitulate hepatic architecture relevant to liver development and disease.
Regenerative medicine, Stem-cell biotechnology, Stem-cell differentiation
A pangenome reference of wild and cultivated rice
Original Paper | Agricultural genetics | 2025-04-15 20:00 EDT
Dongling Guo, Yan Li, Hengyun Lu, Yan Zhao, Nori Kurata, Xinghua Wei, Ahong Wang, Yongchun Wang, Qilin Zhan, Danlin Fan, Congcong Zhou, Yiqi Lu, Qilin Tian, Qijun Weng, Qi Feng, Tao Huang, Lei Zhang, Zhoulin Gu, Changsheng Wang, Ziqun Wang, Zixuan Wang, Xuehui Huang, Qiang Zhao, Bin Han
Oryza rufipogon, the wild progenitor of Asian cultivated rice Oryza sativa, is an important resource for rice breeding1. Here we present a wild-cultivated rice pangenome based on 145 chromosome-level assemblies, comprising 129 genetically diverse O. rufipogon accessions and 16 diverse varieties of O. sativa. This pangenome contains 3.87 Gb of sequences that are absent from the O. sativa ssp. japonica cv. Nipponbare reference genome. We captured alternate assemblies that include heterozygous information missing in the primary assemblies, and identified a total of 69,531 pan-genes, with 28,907 core genes and 13,728 wild-rice-specific genes. We observed a higher abundance and a significantly greater diversity of resistance-gene analogues in wild rice than in cultivars. Our analysis indicates that two cultivated subpopulations, intro-indica and basmati, were generated through gene flows among cultivars in South Asia. We also provide strong evidence to support the theory that the initial domestication of all Asian cultivated rice occurred only once. Furthermore, we captured 855,122 differentiated single-nucleotide polymorphisms and 13,853 differentiated presence-absence variations between indica and japonica, which could be traced to the divergence of their respective ancestors and the existence of a larger genetic bottleneck in japonica. This study provides reference resources for enhancing rice breeding, and enriches our understanding of the origins and domestication process of rice.
Agricultural genetics, Comparative genomics, Evolutionary genetics, Genome evolution, Plant evolution
Structure of the ATP-driven methyl-coenzyme M reductase activation complex
Original Paper | Bioenergetics | 2025-04-15 20:00 EDT
Fidel Ramírez-Amador, Sophia Paul, Anuj Kumar, Christian Lorent, Sebastian Keller, Stefan Bohn, Thinh Nguyen, Stefano Lometto, Dennis Vlegels, Jörg Kahnt, Darja Deobald, Frank Abendroth, Olalla Vázquez, Georg Hochberg, Silvan Scheller, Sven T. Stripp, Jan Michael Schuller
Methyl-coenzyme M reductase (MCR) is the enzyme responsible for nearly all biologically generated methane1. Its active site comprises coenzyme F430, a porphyrin-based cofactor with a central nickel ion that is active exclusively in the Ni(I) state2,3. How methanogenic archaea perform the reductive activation of F430 represents a major gap in our understanding of one of the most ancient bioenergetic systems in nature. Here we purified and characterized the MCR activation complex from Methanococcus maripaludis. McrC, a small subunit encoded in the mcr operon, co-purifies with the methanogenic marker proteins Mmp7, Mmp17, Mmp3 and the A2 component. We demonstrated that this complex can activate MCR in vitro in a strictly ATP-dependent manner, enabling the formation of methane. In addition, we determined the cryo-electron microscopy structure of the MCR activation complex exhibiting different functional states with local resolutions reaching 1.8-2.1 Å. Our data revealed three complex iron-sulfur clusters that formed an electron transfer pathway towards F430. Topology and electron paramagnetic resonance spectroscopy analyses indicate that these clusters are similar to the [8Fe-9S-C] cluster, a maturation intermediate of the catalytic cofactor in nitrogenase. Altogether, our findings offer insights into the activation mechanism of MCR and prospects on the early evolution of nitrogenase.
Bioenergetics, Cryoelectron microscopy, Oxidoreductases
An ultrasensitive method for detection of cell-free RNA
Original Paper | Cancer genomics | 2025-04-15 20:00 EDT
Monica C. Nesselbush, Bogdan A. Luca, Young-Jun Jeon, Isabel Jabara, Catherine B. Meador, Andrea Garofalo, Michael S. Binkley, Angela B. Hui, Iris van ‘t Erve, Nova Xu, William Y. Shi, Kevin J. Liu, Takeshi Sugio, Noah Kastelowitz, Emily G. Hamilton, Chih Long Liu, Mari Olsen, Rene F. Bonilla, Yi Peng Wang, Alice Jiang, Brianna Lau, Jordan Eichholz, Mandeep Banwait, Joseph Schroers-Martin, Jan Boegeholz, Daniel A. King, Helen Luikart, Mohammad S. Esfahani, Mahya Mehrmohamadi, Henning Stehr, Tyler Raclin, Robert Tibshirani, Kiran Khush, Sandy Srinivas, Helena Yu, Angela J. Rogers, Viswam S. Nair, James M. Isbell, Bob T. Li, Zofia Piotrowska, Lecia V. Sequist, Aaron N. Hata, Joel W. Neal, Heather A. Wakelee, Andrew J. Gentles, Ash A. Alizadeh, Maximilian Diehn
Sensitive methods for detection of cell-free RNA (cfRNA) could facilitate non-invasive gene expression profiling and monitoring of diseases1,2,3,4,5,6. Here we describe RARE-seq (random priming and affinity capture of cfRNA fragments for enrichment analysis by sequencing), a method optimized for cfRNA analysis. We demonstrate that platelet contamination can substantially confound cfRNA analyses and develop an approach to overcome it. In analytical validations, we find RARE-seq to be approximately 50-fold more sensitive for detecting tumour-derived cfRNA than whole-transcriptome RNA sequencing (RNA-seq), with a limit of detection of 0.05%. To explore clinical utility, we profiled 437 plasma samples from 369 individuals with cancer or non-malignant conditions and controls. Detection of non-small-cell lung cancer expression signatures in cfRNA increased with stage (6 out of 20 (30%) in stage I; 5 out of 8 (63%) in stage II; 10 out of 15 (67%) in stage III; 80 out of 96 (83% sensitivity) in stage IV at 95% specificity) and RARE-seq was more sensitive than tumour-naive circulating tumour DNA (ctDNA) analysis. In patients with EGFR-mutant non-small-cell lung cancer who developed resistance to tyrosine kinase inhibitors, we detected both histological transformation and mutation-based resistance mechanisms. Finally, we demonstrate the potential utility of RARE-seq for determination of tissue of origin, assessing benign pulmonary conditions and tracking response to mRNA vaccines. These results highlight the potential value of ultrasensitive cfRNA analysis and provide proof of concept for diverse clinical applications.
Cancer genomics, Non-small-cell lung cancer, RNA sequencing
Observation of the axion quasiparticle in 2D MnBi2Te4
Original Paper | Topological matter | 2025-04-15 20:00 EDT
Jian-Xiang Qiu, Barun Ghosh, Jan Schütte-Engel, Tiema Qian, Michael Smith, Yueh-Ting Yao, Junyeong Ahn, Yu-Fei Liu, Anyuan Gao, Christian Tzschaschel, Houchen Li, Ioannis Petrides, Damien Bérubé, Thao Dinh, Tianye Huang, Olivia Liebman, Emily M. Been, Joanna M. Blawat, Kenji Watanabe, Takashi Taniguchi, Kin Chung Fong, Hsin Lin, Peter P. Orth, Prineha Narang, Claudia Felser, Tay-Rong Chang, Ross McDonald, Robert J. McQueeney, Arun Bansil, Ivar Martin, Ni Ni, Qiong Ma, David J. E. Marsh, Ashvin Vishwanath, Su-Yang Xu
The axion is a hypothetical fundamental particle that is conjectured to correspond to the coherent oscillation of the θ field in quantum chromodynamics1,2. Its existence would solve multiple fundamental questions, including the strong CP problem of quantum chromodynamics and dark matter, but the axion has never been detected. Electrodynamics of condensed-matter systems can also give rise to a similar θ, so far studied as a static, quantized value to characterize the topology of materials3,4,5. Coherent oscillation of θ in condensed matter has been proposed to lead to physics directly analogous to the high-energy axion particle–the dynamical axion quasiparticle (DAQ)6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23. Here we report the observation of the DAQ in MnBi2Te4. By combining a two-dimensional electronic device with ultrafast pump-probe optics, we observe a coherent oscillation of θ at about 44 gigahertz, which is uniquely induced by its out-of-phase antiferromagnetic magnon. This represents direct evidence for the presence of the DAQ, which in two-dimensional MnBi2Te4 is found to arise from the magnon-induced coherent modulation of the Berry curvature. The DAQ also has implications in light-matter interaction and coherent antiferromagnetic spintronics24, as it might lead to axion polaritons and electric control of ultrafast spin polarization6,15,16,17,18,19,20. Finally, the DAQ could be used to detect axion particles21,22,23. We estimate the detection frequency range and sensitivity in the millielectronvolt regime, which has so far been poorly explored.
Topological matter, Two-dimensional materials
Subnanosecond flash memory enabled by 2D-enhanced hot-carrier injection
Original Paper | Electronic devices | 2025-04-15 20:00 EDT
Yutong Xiang, Chong Wang, Chunsen Liu, Tanjun Wang, Yongbo Jiang, Yang Wang, Shuiyuan Wang, Peng Zhou
The pursuit of non-volatile memory with program speeds below one nanosecond, beyond the capabilities of non-volatile flash and high-speed volatile static random-access memory, remains a longstanding challenge in the field of memory technology1. Utilizing fundamental physics innovation enabled by advanced materials, series of emerging memories2,3,4,5 are being developed to overcome the speed bottleneck of non-volatile memory. As the most extensively applied non-volatile memory, the speed of flash is limited by the low efficiency of the electric-field-assisted program, with reported speeds6,7,8,9,10 much slower than sub-one nanosecond. Here we report a two-dimensional Dirac graphene-channel flash memory based on a two-dimensional-enhanced hot-carrier-injection mechanism, supporting both electron and hole injection. The Dirac channel flash shows a program speed of 400 picoseconds, non-volatile storage and robust endurance over 5.5 × 106 cycles. Our results confirm that the thin-body channel can optimize the horizontal electric-field (Ey) distribution, and the improved Ey-assisted program efficiency increases the injection current to 60.4 pA μm-1 at |VDS| = 3.7 V. We also find that the two-dimensional semiconductor tungsten diselenide has two-dimensional-enhanced hot-hole injection, but with different injection behaviour. This work demonstrates that the speed of non-volatile flash memory can exceed that of the fastest volatile static random-access memory with the same channel length.
Electronic devices, Electronic properties and devices
A sharp volatile-rich cap to the Yellowstone magmatic system
Original Paper | Natural hazards | 2025-04-15 20:00 EDT
Chenglong Duan, Wenkai Song, Brandon Schmandt, Jamie Farrell, David Lumley, Tobias Fischer, Lindsay Lowe Worthington, Fan-Chi Lin
The stability of hazardous volcanic systems is strongly influenced by the uppermost magma storage depth and volatile exsolution1,2,3. Despite abundant evidence for an upper crustal magma reservoir beneath Yellowstone caldera4,5,6,7, its depth and the properties at its top have not been well constrained. New controlled-source seismic imaging illuminates a sharp reflective cap of the magma reservoir approximately 3.8 km beneath the northeastern caldera. Magma ascent to such low pressure is expected to drive volatile exsolution and potentially localized accumulation of bubbles near the top of the reservoir8,9, but this process typically remains hidden in contemporary volcanic systems. P-wave and P-to-S-wave reflections from the sharp top of the Yellowstone magma reservoir indicate that a mixture of supercritical fluid and magma fills the pore space at the cap of the approximately 3-8-km-deep low-shear-velocity layer imaged by seismic tomography6,7. The results are consistent with partial retention of bubbles exsolved from an upper crustal reservoir with ongoing magma supply from a volatile-enriched mantle source. Bubble accumulation can eventually lead to reservoir instability2,8, but the bubble volume fraction seismically estimated at the top of the reservoir today is lower than typical estimates of pre-eruptive conditions for rhyolites1,10,11, and measurements of the hydrothermal system document high fluxes of magmatic volatiles escaping to the surface12,13,14,-15. We infer that the magma reservoir is in a stable state of efficient bubble ascent into the hydrothermal system on the basis of estimates that it is a crystal-rich (less than 30% porosity) reservoir for which dynamic modelling favours channelized bubble escape that prevents instability8.
Natural hazards, Volcanology
Driven bright solitons on a mid-infrared laser chip
Original Paper | Frequency combs | 2025-04-15 20:00 EDT
Dmitry Kazakov, Theodore P. Letsou, Marco Piccardo, Lorenzo L. Columbo, Massimo Brambilla, Franco Prati, Sandro Dal Cin, Maximilian Beiser, Nikola Opačak, Pawan Ratra, Michael Pushkarsky, David Caffey, Timothy Day, Luigi A. Lugiato, Benedikt Schwarz, Federico Capasso
Despite the continuing progress in integrated optical frequency comb technology1, compact sources of short, bright pulses in the mid-infrared wavelength range from 3 to 12 μm so far remain beyond reach. The state-of-the-art ultrafast pulse emitters in the mid-infrared are complex, bulky and inefficient systems based on the downconversion of near-infrared or visible pulsed laser sources. Here we show a purely DC-driven semiconductor laser chip that generates 1-ps solitons at the centre wavelength of 8.3 μm at GHz repetition rates. The soliton generation scheme is akin to that of passive nonlinear Kerr resonators2. It relies on a fast bistability in active nonlinear laser resonators, unlike traditional passive mode-locking, which relies on saturable absorbers3, or active mode-locking by gain modulation in semiconductor lasers4. Monolithic integration of all components–drive laser, active ring resonator, coupler and pump filter–enables turnkey generation of bright solitons that remain robust for hours of continuous operation without active stabilization. Such devices can be readily produced at industrial laser foundries using standard fabrication protocols. Our work unifies the physics of active and passive microresonator frequency combs while simultaneously establishing a technology for nonlinear integrated photonics in the mid-infrared5.
Frequency combs, Integrated optics, Mid-infrared photonics, Optoelectronic devices and components, Solitons
Phase I/II trial of iPS-cell-derived dopaminergic cells for Parkinson’s disease
Original Paper | Induced pluripotent stem cells | 2025-04-15 20:00 EDT
Nobukatsu Sawamoto, Daisuke Doi, Etsuro Nakanishi, Masanori Sawamura, Takayuki Kikuchi, Hodaka Yamakado, Yosuke Taruno, Atsushi Shima, Yasutaka Fushimi, Tomohisa Okada, Tetsuhiro Kikuchi, Asuka Morizane, Satoe Hiramatsu, Takayuki Anazawa, Takero Shindo, Kentaro Ueno, Satoshi Morita, Yoshiki Arakawa, Yuji Nakamoto, Susumu Miyamoto, Ryosuke Takahashi, Jun Takahashi
Parkinson’s disease is caused by the loss of dopamine neurons, causing motor symptoms. Initial cell therapies using fetal tissues showed promise but had complications and ethical concerns1,2,3,4,5. Pluripotent stem (PS) cells emerged as a promising alternative for developing safe and effective treatments6. In this phase I/II trial at Kyoto University Hospital, seven patients (ages 50-69) received bilateral transplantation of dopaminergic progenitors derived from induced PS (iPS) cells. Primary outcomes focused on safety and adverse events, while secondary outcomes assessed motor symptom changes and dopamine production for 24 months. There were no serious adverse events, with 73 mild to moderate events. Patients’ anti-parkinsonian medication doses were maintained unless therapeutic adjustments were required, resulting in increased dyskinesia. Magnetic resonance imaging showed no graft overgrowth. Among six patients subjected to efficacy evaluation, four showed improvements in the Movement Disorder Society Unified Parkinson’s Disease Rating Scale part III OFF score, and five showed improvements in the ON scores. The average changes of all six patients were 9.5 (20.4%) and 4.3 points (35.7%) for the OFF and ON scores, respectively. Hoehn-Yahr stages improved in four patients. Fluorine-18-l-dihydroxyphenylalanine (18F-DOPA) influx rate constant (Ki) values in the putamen increased by 44.7%, with higher increases in the high-dose group. Other measures showed minimal changes. This trial (jRCT2090220384) demonstrated that allogeneic iPS-cell-derived dopaminergic progenitors survived, produced dopamine and did not form tumours, therefore suggesting safety and potential clinical benefits for Parkinson’s disease.
Induced pluripotent stem cells, Parkinson’s disease
Chromosome end protection by RAP1-mediated inhibition of DNA-PK
Original Paper | Non-homologous-end joining | 2025-04-15 20:00 EDT
Patrik Eickhoff, Ceylan Sonmez, Charlotte E. L. Fisher, Oviya Inian, Theodoros I. Roumeliotis, Angela dello Stritto, Jörg Mansfeld, Jyoti S. Choudhary, Sebastian Guettler, Francisca Lottersberger, Max E. Douglas
During classical non-homologous end joining (cNHEJ), DNA-dependent protein kinase (DNA-PK) encapsulates free DNA ends, forming a recruitment platform for downstream end-joining factors including ligase 4 (LIG4)1. DNA-PK can also bind telomeres and regulate their resection2,3,4, but does not initiate cNHEJ at this position. How the end-joining process is regulated in this context-specific manner is currently unclear. Here we show that the shelterin components TRF2 and RAP1 form a complex with DNA-PK that directly represses its end-joining function at telomeres. Biochemical experiments and cryo-electron microscopy reveal that when bound to TRF2, RAP1 establishes a network of interactions with KU and DNA that prevents DNA-PK from recruiting LIG4. In mouse and human cells, RAP1 is redundant with the Apollo nuclease in repressing cNHEJ at chromosome ends, demonstrating that the inhibition of DNA-PK prevents telomere fusions in parallel with overhang-dependent mechanisms. Our experiments show that the end-joining function of DNA-PK is directly and specifically repressed at telomeres, establishing a molecular mechanism for how individual linear chromosomes are maintained in mammalian cells.
Non-homologous-end joining, Telomeres
The growing memristor industry
Review Paper | Electrical and electronic engineering | 2025-04-15 20:00 EDT
Mario Lanza, Sebastian Pazos, Fernando Aguirre, Abu Sebastian, Manuel Le Gallo, Syed M. Alam, Sumio Ikegawa, J. Joshua Yang, Elisa Vianello, Meng-Fan Chang, Gabriel Molas, Ishai Naveh, Daniele Ielmini, Ming Liu, Juan B. Roldan
The semiconductor industry is experiencing an accelerated transformation to overcome the scaling limits of the transistor and to adapt to new requirements in terms of data storage and computation, especially driven by artificial intelligence applications and the Internet of Things. In this process, new materials, devices, integration strategies and system architectures are being developed and optimized. Among them, memristive devices and circuits–memristors are two-terminal memory devices that can also mimic some basic bioelectronic functions–offer a potential approach to create more compact, energy-efficient or better-performing systems. The memristor industry is growing quickly, raising abundant capital investment, creating new jobs and placing advanced products in the market. Here we analyse the status and prospects of the memristor industry, focusing on memristor-based products that are already commercially available, prototypes with a high technological readiness level that might affect the market in the near future, and discuss obstacles and pathways to their implementation.
Electrical and electronic engineering, Electronic devices
Antiferromagnetic quantum anomalous Hall effect under spin flips and flops
Original Paper | Magnetic properties and materials | 2025-04-15 20:00 EDT
Zichen Lian, Yongchao Wang, Yongqian Wang, Wen-Han Dong, Yang Feng, Zehao Dong, Mangyuan Ma, Shuai Yang, Liangcai Xu, Yaoxin Li, Bohan Fu, Yuetan Li, Wanjun Jiang, Yong Xu, Chang Liu, Jinsong Zhang, Yayu Wang
The interplay between nontrivial band topology and layered antiferromagnetism in MnBi2Te4 has opened a new avenue for exploring topological phases of matter1,2,3,4. The quantum anomalous Hall effect5 and axion insulator state6 have been observed in odd and even number layers of MnBi2Te4, and the quantum metric nonlinear Hall effect7,8 has been shown to exist in this topological antiferromagnet. The rich and complex antiferromagnetic spin dynamics in MnBi2Te4 is expected to generate new quantum anomalous Hall phenomena that are absent in conventional ferromagnetic topological insulators, but experimental observations are still unknown. Here we fabricate a device of 7-septuple-layer MnBi2Te4 covered with an AlOx capping layer, which enables the investigation of antiferromagnetic quantum anomalous Hall effect over wide parameter spaces. By tuning the gate voltage and perpendicular magnetic field, we uncover a cascade of quantum phase transitions that can be attributed to the influence of complex spin configurations on edge state transport. Furthermore, we find that an in-plane magnetic field enhances both the coercive field and the exchange gap of the surface state, in contrast to that in the ferromagnetic quantum anomalous Hall state. Combined with numerical simulations, we propose that these peculiar features arise from the spin flip and flop transitions that are inherent to a van der Waals antiferromagnet. The versatile tunability of the quantum anomalous Hall effect in MnBi2Te4 paves the way for potential applications in topological antiferromagnetic spintronics9,10.
Magnetic properties and materials, Topological insulators
Perturbing LSD1 and WNT rewires transcription to synergistically induce AML differentiation
Original Paper | Acute myeloid leukaemia | 2025-04-15 20:00 EDT
Amir Hosseini, Abhinav Dhall, Nemo Ikonen, Natalia Sikora, Sylvain Nguyen, Yuqi Shen, Maria Luisa Jurgensen Amaral, Alan Jiao, Felice Wallner, Philipp Sergeev, Yuhua Lim, Yuanqin Yang, Binje Vick, Kimihito Cojin Kawabata, Ari Melnick, Paresh Vyas, Bing Ren, Irmela Jeremias, Bethan Psaila, Caroline A. Heckman, M. Andrés Blanco, Yang Shi
Impaired differentiation is a hallmark of myeloid malignancies1,2. Therapies that enable cells to circumvent the differentiation block, such as all-trans retinoic acid (ATRA) and arsenic trioxide (ATO), are by and large curative in acute promyelocytic leukaemia3, but whether ‘differentiation therapy’ is a generalizable therapeutic approach for acute myeloid leukaemia (AML) and beyond remains incompletely understood. Here we demonstrate that simultaneous inhibition of the histone demethylase LSD1 (LSD1i) and the WNT pathway antagonist GSK3 kinase4 (GSK3i) robustly promotes therapeutic differentiation of established AML cell lines and primary human AML cells, as well as reducing tumour burden and significantly extending survival in a patient-derived xenograft mouse model. Mechanistically, this combination promotes differentiation by activating genes in the type I interferon pathway via inducing expression of transcription factors such as IRF7 (LSD1i) and the co-activator β-catenin (GSK3i), and their selective co-occupancy at targets such as STAT1, which is necessary for combination-induced differentiation. Combination treatment also suppresses the canonical, pro-oncogenic WNT pathway and cell cycle genes. Analysis of datasets from patients with AML suggests a correlation between the combination-induced transcription signature and better prognosis, highlighting clinical potential of this strategy. Collectively, this combination strategy rewires transcriptional programs to suppress stemness and to promote differentiation, which may have important therapeutic implications for AML and WNT-driven cancers beyond AML.
Acute myeloid leukaemia, Targeted therapies
Histone H1 deamidation facilitates chromatin relaxation for DNA repair
Original Paper | Histone post-translational modifications | 2025-04-15 20:00 EDT
Yuan Tian, Tingting Feng, Jun Zhang, Qingren Meng, Wenxin Zhan, Ming Tang, Chaohua Liu, Mengyan Li, Wenhui Tao, Yuxin Shu, Yu Zhang, Feng Chen, Shunichi Takeda, Qian Zhu, Xiaopeng Lu, Wei-Guo Zhu
The formation of accessible chromatin around DNA double-strand breaks is essential for their efficient repair1. Although the linker histone H1 is known to facilitate higher-order chromatin compaction2,3, the mechanisms by which H1 modifications regulate chromatin relaxation in response to DNA damage are unclear. Here we show that CTP synthase 1 (CTPS1)-catalysed deamidation of H1 asparagine residues 76 and 77 triggers the sequential acetylation of lysine 75 following DNA damage, and this dual modification of H1 is associated with chromatin opening. Mechanistically, the histone acetyltransferase p300 showed a preference for deamidated H1 as a substrate, establishing H1 deamidation as a prerequisite for subsequent acetylation. Moreover, high expression of CTPS1 was associated with resistance to cancer radiotherapy, in both mouse xenograft models and clinical cohorts. These findings provide new insights into how linker histones regulate dynamic chromatin alterations in the DNA damage response.
Histone post-translational modifications, Radiotherapy
Re-adenylation by TENT5A enhances efficacy of SARS-CoV-2 mRNA vaccines
Original Paper | RNA metabolism | 2025-04-15 20:00 EDT
Paweł S. Krawczyk, Michał Mazur, Wiktoria Orzeł, Olga Gewartowska, Sebastian Jeleń, Wiktor Antczak, Karolina Kasztelan, Aleksandra Brouze, Katarzyna Matylla-Kulińska, Natalia Gumińska, Bartosz Tarkowski, Ewelina P. Owczarek, Kamila Affek, Paweł Turowski, Agnieszka Tudek, Małgorzata Sroka, Tomasz Śpiewla, Monika Kusio-Kobiałka, Aleksandra Wesołowska, Dominika Nowis, Jakub Golab, Joanna Kowalska, Jacek Jemielity, Andrzej Dziembowski, Seweryn Mroczek
Despite the widespread use of mRNA vaccines against COVID-19, little is known about the metabolism of therapeutic RNAs. Here we use nanopore sequencing1,2,3 to analyse individual therapeutic mRNA molecules, focusing on their poly(A) tails. We show that the Moderna mRNA-1273 vaccine4 has a poly(A) tail of around 100 nucleotides, followed by an mΨCmΨAG sequence. In cell lines, mRNA-1273 undergoes rapid degradation initiated by mΨCmΨAG removal, followed by CCR4-NOT-mediated deadenylation. However, in medically relevant preclinical models, particularly in macrophages, mRNA-1273 poly(A) tails are extended to up to 200 nucleotides by the TENT5A poly(A) polymerase5,6,7, which is induced by the vaccine. Re-adenylation, which stabilizes target mRNAs, is consistently observed in synthetic mRNAs that encode proteins targeted to the endoplasmic reticulum, such as ovalbumin or antigens from Zika virus8 or the malaria parasite9. The extent of re-adenylation varies: the BioNTech-Pfizer BNT162b2 vaccine10 shows less potent re-adenylation than mRNA-1273, which correlates with a smaller proportion of membrane-associated BNT162b2. This highlights the crucial role of spatial accessibility to ER-resident TENT5A in determining re-adenylation efficiency. In vivo, TENT5A is expressed in immune cells that take up mRNA vaccine, and TENT5A deficiency reduces specific immunoglobulin production for mRNA vaccines after immunization in mice. Overall, our findings reveal a principle for enhancing the efficacy of therapeutic mRNAs, paving the way for improvement.
RNA metabolism, RNA vaccines
Towards multimodal foundation models in molecular cell biology
Review Paper | Cell biology | 2025-04-15 20:00 EDT
Haotian Cui, Alejandro Tejada-Lapuerta, Maria Brbić, Julio Saez-Rodriguez, Simona Cristea, Hani Goodarzi, Mohammad Lotfollahi, Fabian J. Theis, Bo Wang
The rapid advent of high-throughput omics technologies has created an exponential growth in biological data, often outpacing our ability to derive molecular insights. Large-language models have shown a way out of this data deluge in natural language processing by integrating massive datasets into a joint model with manifold downstream use cases. Here we envision developing multimodal foundation models, pretrained on diverse omics datasets, including genomics, transcriptomics, epigenomics, proteomics, metabolomics and spatial profiling. These models are expected to exhibit unprecedented potential for characterizing the molecular states of cells across a broad continuum, thereby facilitating the creation of holistic maps of cells, genes and tissues. Context-specific transfer learning of the foundation models can empower diverse applications from novel cell-type recognition, biomarker discovery and gene regulation inference, to in silico perturbations. This new paradigm could launch an era of artificial intelligence-empowered analyses, one that promises to unravel the intricate complexities of molecular cell biology, to support experimental design and, more broadly, to profoundly extend our understanding of life sciences.
Cell biology, Computational models, Functional genomics, Genomics, Machine learning
Generation of human adult hepatocyte organoids with metabolic functions
Original Paper | Adult stem cells | 2025-04-15 20:00 EDT
Ryo Igarashi, Mayumi Oda, Ryo Okada, Tomoki Yano, Sirirat Takahashi, Strahil Pastuhov, Mami Matano, Norio Masuda, Kazuhiro Togasaki, Yuki Ohta, Saeko Sato, Takako Hishiki, Makoto Suematsu, Manabu Itoh, Masayuki Fujii, Toshiro Sato
Proliferating hepatocytes often undergo ductal metaplasia to balance the energy trade-off between cellular functions and replication, hindering the expansion of human adult hepatocytes with functional competency1. Here we demonstrate that the combined activation of Wnt and STAT3 signalling enables long-term self-renewal of human adult hepatocyte organoids. YAP activation facilitates hepatocyte proliferation but commits it towards the biliary duct lineage. By contrast, STAT3 activation by oncostatin M induces hepatocyte proliferation while counteracting ductal metaplasia and maintaining the hepatic identity. Xenotransplanted hepatocyte organoids repopulate the recipient mouse liver and reconstitute the metabolic zonation structure. Upon niche factor removal and hormone supplementation, hepatocyte organoids form cord-like structures with bile canalicular networks and exhibit major liver metabolic functions comparable to those of in vivo hepatocytes. Hepatocyte organoids are amenable to gene editing, prompting functional modelling of inherent metabolic liver diseases. The new culture system offers a promising avenue for developing therapeutic strategies against human liver diseases.
Adult stem cells, Cell adhesion, Stem-cell biotechnology, Stem-cell research
Deep Visual Proteomics maps proteotoxicity in a genetic liver disease
Original Paper | Mass spectrometry | 2025-04-15 20:00 EDT
Florian A. Rosenberger, Sophia C. Mädler, Katrine Holtz Thorhauge, Sophia Steigerwald, Malin Fromme, Mikhail Lebedev, Caroline A. M. Weiss, Marc Oeller, Maria Wahle, Andreas Metousis, Maximilian Zwiebel, Niklas A. Schmacke, Sönke Detlefsen, Peter Boor, Ondřej Fabián, Soňa Fraňková, Aleksander Krag, Pavel Strnad, Matthias Mann
Protein misfolding diseases, including α1-antitrypsin deficiency (AATD), pose substantial health challenges, with their cellular progression still poorly understood1,2,3. We use spatial proteomics by mass spectrometry and machine learning to map AATD in human liver tissue. Combining Deep Visual Proteomics (DVP) with single-cell analysis4,5, we probe intact patient biopsies to resolve molecular events during hepatocyte stress in pseudotime across fibrosis stages. We achieve proteome depth of up to 4,300 proteins from one-third of a single cell in formalin-fixed, paraffin-embedded tissue. This dataset reveals a potentially clinically actionable peroxisomal upregulation that precedes the canonical unfolded protein response. Our single-cell proteomics data show α1-antitrypsin accumulation is largely cell-intrinsic, with minimal stress propagation between hepatocytes. We integrated proteomic data with artificial intelligence-guided image-based phenotyping across several disease stages, revealing a late-stage hepatocyte phenotype characterized by globular protein aggregates and distinct proteomic signatures, notably including elevated TNFSF10 (also known as TRAIL) amounts. This phenotype may represent a critical disease progression stage. Our study offers new insights into AATD pathogenesis and introduces a powerful methodology for high-resolution, in situ proteomic analysis of complex tissues. This approach holds potential to unravel molecular mechanisms in various protein misfolding disorders, setting a new standard for understanding disease progression at the single-cell level in human tissue.
Mass spectrometry, Mechanisms of disease, Proteomic analysis
Wide-swath satellite altimetry unveils global submesoscale ocean dynamics
Original Paper | Physical oceanography | 2025-04-15 20:00 EDT
Matthew Archer, Jinbo Wang, Patrice Klein, Gerald Dibarboure, Lee-Lueng Fu
Ocean submesoscale (1-100 km) processes and their substantial impact on Earth’s climate system have been increasingly emphasized in recent decades by high-resolution numerical models and regional observations1,2,3,4,5,6,7,8,9,10,11. However, the dynamics and energy associated with these processes, including submesoscale eddies and nonlinear internal waves, have never been observed from a global perspective. Where, when and how much do these submesoscale processes contribute to the large-scale ocean circulation and climate system? Here we show data from the recently launched Surface Water and Ocean Topography (SWOT) satellite12 that not only confirm the characteristics of submesoscale eddies and waves but also suggest that their potential impacts on ocean energetics, the marine ecosystem, atmospheric weather and Earth’s climate system are much larger than anticipated. SWOT ushers in a new era of global ocean observing, placing submesoscale ocean dynamics as a critical element of the Earth’s climate system.
Physical oceanography
Low overlap of transcription factor DNA binding and regulatory targets
Original Paper | Transcriptional regulatory elements | 2025-04-15 20:00 EDT
Lakshmi Mahendrawada, Linda Warfield, Rafal Donczew, Steven Hahn
DNA sequence-specific transcription factors (TFs) modulate transcription and chromatin architecture, acting from regulatory sites in enhancers and promoters of eukaryotic genes1,2. How multiple TFs cooperate to regulate individual genes is still unclear. In yeast, most TFs are thought to regulate transcription via binding to upstream activating sequences, which are situated within a few hundred base pairs upstream of the regulated gene3. Although this model has been validated for individual TFs and specific genes, it has not been tested in a systematic way. Here we integrated information on the binding and expression targets for the near-complete set of yeast TFs and show that, contrary to expectations, there are few TFs with dedicated activator or repressor roles, and that most TFs have a dual function. Although nearly all protein-coding genes are regulated by one or more TFs, our analysis revealed limited overlap between TF binding and gene regulation. Rapid depletion of many TFs also revealed many regulatory targets that were distant from detectable TF binding sites, suggesting unexpected regulatory mechanisms. Our study provides a comprehensive survey of TF functions and offers insights into interactions between the set of TFs expressed in a single cell type and how they contribute to the complex programme of gene regulation.
Transcriptional regulatory elements, Transcriptomics
Phase I trial of hES cell-derived dopaminergic neurons for Parkinson’s disease
Original Paper | Embryonic stem cells | 2025-04-15 20:00 EDT
V. Tabar, H. Sarva, A. M. Lozano, A. Fasano, S. K. Kalia, K. K. H. Yu, C. Brennan, Y. Ma, S. Peng, D. Eidelberg, M. Tomishima, S. Irion, W. Stemple, N. Abid, A. Lampron, L. Studer, C. Henchcliffe
Parkinson’s disease is a progressive neurodegenerative condition with a considerable health and economic burden1. It is characterized by the loss of midbrain dopaminergic neurons and a diminished response to symptomatic medical or surgical therapy as the disease progresses2. Cell therapy aims to replenish lost dopaminergic neurons and their striatal projections by intrastriatal grafting. Here, we report the results of an open-label phase I clinical trial (NCT04802733) of an investigational cryopreserved, off-the-shelf dopaminergic neuron progenitor cell product (bemdaneprocel) derived from human embryonic stem (hES) cells and grafted bilaterally into the putamen of patients with Parkinson’s disease. Twelve patients were enrolled sequentially in two cohorts–a low-dose (0.9 million cells, n = 5) and a high-dose (2.7 million cells, n = 7) cohort–and all of the participants received one year of immunosuppression. The trial achieved its primary objectives of safety and tolerability one year after transplantation, with no adverse events related to the cell product. At 18 months after grafting, putaminal 18Fluoro-DOPA positron emission tomography uptake increased, indicating graft survival. Secondary and exploratory clinical outcomes showed improvement or stability, including improvement in the Movement Disorder Society Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) Part III OFF scores by an average of 23 points in the high-dose cohort. There were no graft-induced dyskinesias. These data demonstrate safety and support future definitive clinical studies.
Embryonic stem cells, Movement disorders, Neuroscience, Parkinson’s disease
Negative thermal expansion and oxygen-redox electrochemistry
Original Paper | Batteries | 2025-04-15 20:00 EDT
Bao Qiu, Yuhuan Zhou, Haoyan Liang, Minghao Zhang, Kexin Gu, Tao Zeng, Zhou Zhou, Wen Wen, Ping Miao, Lunhua He, Yinguo Xiao, Sven Burke, Zhaoping Liu, Ying Shirley Meng
Structural disorder within materials gives rise to fascinating phenomena, attributed to the intricate interplay of their thermodynamic and electrochemical properties1,2. Oxygen-redox (OR) electrochemistry offers a breakthrough in capacity limits, while inducing structural disorder with reduced electrochemical reversibility3,4,5. The conventional explanation for the thermal expansion of solids relies on the Grüneisen relationship, linking the expansion coefficient to the anharmonicity of the crystal lattice6. However, this paradigm may not be applicable to OR materials due to the unexplored dynamic disorder-order transition in such systems7,8. Here we reveal the presence of negative thermal expansion with a large coefficient value of -14.4(2) × 10-6 °C-1 in OR active materials, attributing this to thermally driven disorder-order transitions. The modulation of OR behaviour not only enables precise control over the thermal expansion coefficient of materials, but also establishes a pragmatic framework for the design of functional materials with zero thermal expansion. Furthermore, we demonstrate that the reinstatement of structural disorder within the material can also be accomplished through the electrochemical driving force. By adjusting the cut-off voltages, evaluation of the discharge voltage change indicates a potential for nearly 100% structure recovery. This finding offers a pathway for restoring OR active materials to their pristine state through operando electrochemical processes, presenting a new mitigation strategy to address the persistent challenge of voltage decay.
Batteries
Nature Nanotechnology
Homogeneous 2D/3D heterostructured tin halide perovskite photovoltaics
Original Paper | Energy science and technology | 2025-04-15 20:00 EDT
Dongxu He, Peng Chen, Julian A. Steele, Zhiliang Wang, Hongyi Xu, Meng Zhang, Shanshan Ding, Chengxi Zhang, Tongen Lin, Felipe Kremer, Hongzhe Xu, Mengmeng Hao, Lianzhou Wang
Tin halide perovskites (THPs) have emerged as promising lead-free candidates for eco-friendly perovskite solar cells, but their photovoltaic performance still lags behind that of lead-based counterparts due to poor thin-film quality. Constructing two-dimensional/three-dimensional (2D/3D) heterostructures can effectively regulate crystallization and suppress defect formation for developing high-quality THP thin films. However, the high aggregation barrier prevents large 2D perovskite colloids from forming stable clusters, making 2D THPs nucleate more slowly than their 3D analogues. Such distinct nucleation kinetics cause undesirable 2D/3D phase segregation that compromises both photovoltaic performance and device durability. Here we introduce small inorganic caesium cations to partially replace bulky organic cations in the electrical double layers of 2D THP colloids, reducing the colloid size to lower their aggregation barrier. The reduced electrostatic repulsion promotes the coagulation of 2D and 3D THP colloids in the precursor solution, synchronizing their nucleation kinetics for the growth of 2D/3D heterostructured THP thin films with a homogeneous microstructure and markedly reduced trap states. Consequently, the caesium-incorporated THP solar cells deliver an excellent power conversion efficiency of 17.13% (certified 16.65%) and exhibit stable operation under continuous one-sun illumination for over 1,500 h in nitrogen without encapsulation. This study offers new insights into the colloidal chemistry and crystallization engineering of mixed-dimensional heterostructures, paving the way for high-performance lead-free perovskite photovoltaics.
Energy science and technology, Materials science
Physical Review Letters
Time-Resolved Stochastic Dynamics of Quantum Thermal Machines
Research article | Open quantum systems | 2025-04-15 06:00 EDT
Abhaya S. Hegde, Patrick P. Potts, and Gabriel T. Landi
Steady-state quantum thermal machines are typically characterized by a continuous flow of heat between different reservoirs. However, at the level of discrete stochastic realizations, heat flow is unraveled as a series of abrupt quantum jumps, each representing an exchange of finite quanta with the environment. In this work, we present a framework that resolves the dynamics of quantum thermal machines into cycles classified as enginelike, coolinglike, or idle. We analyze the statistics of individual cycle types and their durations, enabling us to determine both the fraction of cycles useful for thermodynamic tasks and the average waiting time between cycles of a given type. Central to our analysis is the notion of intermittency, which captures the operational consistency of the machine by assessing the frequency and distribution of idle cycles. Our framework offers a novel approach to characterizing thermal machines, with significant relevance to experiments involving mesoscopic transport through quantum dots.
Phys. Rev. Lett. 134, 150402 (2025)
Open quantum systems, Quantum statistical mechanics, Quantum stochastic processes, Quantum heat engines & refrigerators, Full counting statistics, Quantum master equation
Clifford Dressed Time-Dependent Variational Principle
Research article | Quantum algorithms & computation | 2025-04-15 06:00 EDT
Antonio Francesco Mello, Alessandro Santini, Guglielmo Lami, Jacopo De Nardis, and Mario Collura
We propose an enhanced time-dependent variational principle (TDVP) algorithm for matrix product states that integrates Clifford disentangling techniques to efficiently manage entanglement growth. By leveraging the Clifford group, which maps Pauli strings to other Pauli strings while maintaining low computational complexity, we introduce a Clifford dressed single-site 1-TDVP scheme. During the TDVP integration, we apply a global Clifford transformation as needed to reduce entanglement by iteratively sweeping over two-qubit Clifford unitaries that connect neighboring sites in a checkerboard pattern. We validate the new algorithm numerically using various quantum many-body models, including both integrable and nonintegrable systems. Our results demonstrate that the Clifford dressed TDVP significantly improves entanglement management and computational efficiency, achieving higher accuracy, extended simulation times, and enhanced precision in computed observables compared to standard TDVP approaches. Additionally, we propose incorporating Clifford gates directly within the two-site 2-TDVP scheme.
Phys. Rev. Lett. 134, 150403 (2025)
Quantum algorithms & computation, Quantum circuits, Quantum simulation, Tensor network methods
Clifford Circuits Augmented Time-Dependent Variational Principle
Research article | Quantum many-body systems | 2025-04-15 06:00 EDT
Xiangjian Qian, Jiale Huang, and Mingpu Qin
The recently proposed Clifford circuits augmented matrix product states (CA-MPSs) [, , and , Phys. Rev. Lett. 133, 190402 (2024)] seamlessly augment density matrix renormalization groups with Clifford circuits. In CA-MPSs, the entanglement from stabilizers is transferred to the Clifford circuits, which can be easily handled according to the Gottesman-Knill theorem. As a result, an MPS needs only to deal with the nonstabilizer entanglement, which largely reduces the bond dimension and the resource required for the accurate simulation of many-body systems. In this Letter, we generalize CA-MPSs to the framework of the time-dependent variational principle (TDVP) for time evolution simulations. In this method, we apply Clifford circuits to the resulting MPS in each TDVP step with a two-site sweeping process similar as in density matrix renormalization groups, aiming at reducing the entanglement entropy in the MPS, and the Hamiltonian is transformed accordingly using the chosen Clifford circuits. Similar as in CA-MPSs, the Clifford circuits does not increase the number of terms in the Hamiltonian, which makes the overhead very small in the new method. We test this method in $XXZ$ chain, 2D Heisenberg model, and Kitaev honeycomb model. The results show that the Clifford circuits augmented TDVP method can reduce the entanglement entropy in the time evolution process and hence makes the simulation reliable for a longer time. The Clifford circuits augmented time-dependent variational principle provides a useful tool for the simulation of the time evolution process of many-body systems in the future.
Phys. Rev. Lett. 134, 150404 (2025)
Quantum many-body systems, Density matrix renormalization group, Matrix product states
Efficient Detection of Strong-To-Weak Spontaneous Symmetry Breaking via the R'enyi-1 Correlator
Open quantum systems & decoherence | 2025-04-15 06:00 EDT
Zack Weinstein
Strong-to-weak spontaneous symmetry breaking (SWSSB) has recently emerged as a universal feature of quantum mixed-state phases of matter. While various information-theoretic diagnostics have been proposed to define and characterize SWSSB phases, relating these diagnostics to observables which can be efficiently and scalably probed on modern quantum devices remains challenging. Here we propose a new observable for SWSSB in mixed states, called the R'enyi-1 correlator, which naturally suggests a route toward scalably detecting certain SWSSB phases in experiment. Specifically, if the canonical purification (CP) of a given mixed state can be reliably prepared, then SWSSB in the mixed state can be detected via ordinary two-point correlation functions in the CP state. We discuss several simple examples of CP states which can be efficiently prepared on quantum devices, and whose reduced density matrices exhibit SWSSB. The R'enyi-1 correlator also satisfies several useful theoretical properties: it naturally inherits a stability theorem recently proven for the closely related fidelity correlator, and it directly defines SWSSB as a particular pattern of ordinary spontaneous symmetry breaking in the CP state.
Phys. Rev. Lett. 134, 150405 (2025)
Open quantum systems & decoherence, Quantum correlations in quantum information, Quantum phase transitions, Quantum simulation, Symmetries in condensed matter
Accessing Universal Relations of Binary Neutron Star Waveforms in Massive Scalar-Tensor Theory
Research article | Alternative gravity theories | 2025-04-15 06:00 EDT
Alan Tsz-Lok Lam, Yong Gao, Hao-Jui Kuan, Masaru Shibata, Karim Van Aelst, and Kenta Kiuchi
We investigate how the quasiuniversal relations connecting tidal deformability with gravitational waveform characteristics and/or properties of individual neutron stars that were proposed in the literature within general relativity would be influenced in the massive Damour-Esposito-Farese-type scalar-tensor gravity. For this purpose, we systematically perform numerical relativity simulations of $\sim 120$ binary neutron-star mergers with varying scalar coupling constants. Although only three neutron-star equations of state are adopted, a clear breach of universality can be observed in the datasets. In addition to presenting difficulties in constructing quasiuniversal relations in alternative gravity theories, we also briefly compare the impacts of non-general-relativity physics on the waveform features and those due to the first order or cross-over quantum chromodynamical phase transition.
Phys. Rev. Lett. 134, 151402 (2025)
Alternative gravity theories, Astrophysical studies of gravity, Gravitational waves, Binary stars, Neutron stars & pulsars, Astrophysical & cosmological simulations, Numerical relativity, Numerical simulations in gravitation & astrophysics
Flow-Based Sampling for Entanglement Entropy and the Machine Learning of Defects
Research article | Entanglement in field theory | 2025-04-15 06:00 EDT
Andrea Bulgarelli, Elia Cellini, Karl Jansen, Stefan Kühn, Alessandro Nada, Shinichi Nakajima, Kim A. Nicoli, and Marco Panero
We introduce a novel technique to numerically calculate R'enyi entanglement entropies in lattice quantum field theory using generative models. We describe how flow-based approaches can be combined with the replica trick using a custom neural-network architecture around a lattice defect connecting two replicas. Numerical tests for the ${\phi }^{4}$ scalar field theory in two and three dimensions demonstrate that our technique outperforms state-of-the-art Monte Carlo calculations, and exhibit a promising scaling with the defect size.
Phys. Rev. Lett. 134, 151601 (2025)
Entanglement in field theory, Statistical field theory, Lattice field theory, Machine learning, Monte Carlo methods
${\mathrm{AdS}}_{3}\times{}{\mathrm{S}}^{3}$ Virasoro-Shapiro Amplitude with Ramond-Ramond Flux
Strings & branes | 2025-04-15 06:00 EDT
Shai M. Chester and De-liang Zhong (钟德亮)
We compute the anti–de Sitter Virasoro-Shapiro amplitude for scattering of dilatons in type IIB string theory with pure Ramond-Ramond flux on ${\mathrm{AdS}}{3}\times{}{S}^{3}\times{}{M}{4}$ for ${M}_{4}={T}^{4}$ or $K3$, to all orders in ${\alpha }^{‘ }$ in a small anti–de Sitter curvature expansion. This is achieved by comparing the flat space limit of the dual D1D5 conformal field theory correlator to an ansatz for the amplitude as a world-sheet integral in terms of single valued multiple polylogarithms. The first curvature correction is fully fixed in this way, and satisfies consistency checks in the high energy limit, and by comparison of the energy of massive string operators to a semiclassical expansion. Our result gives infinite predictions for conformal field theory data in the planar limit at strong coupling, which can guide future integrability studies.
Phys. Rev. Lett. 134, 151602 (2025)
Strings & branes, Conformal symmetry
Emergence of Second-Order Coherence in the Superradiant Emission from a Free-Space Atomic Ensemble
Research article | Atomic & molecular processes in external fields | 2025-04-15 06:00 EDT
Giovanni Ferioli, Igor Ferrier-Barbut, and Antoine Browaeys
We investigate the evolution of the second-order temporal coherence during the emission of a superradiant pulse by an elongated cloud of cold Rb atoms in free space. To do so, we measure the two-times intensity correlation function ${g}{N}^{(2)}({t}{1},{t}{2})$ following the pulsed excitation of the cloud. By monitoring ${g}{N}^{(2)}(t,t)$ during the pulse, we observe the establishment of second-order coherence, and contrast it with the situation where the cloud is initially prepared in a steady state. We compare our findings to the predictions of the Dicke model, using an effective atom number to account for finite size effects, finding that the model reproduces the observed trend at early time. For longer times, we observe a subradiant decay, a feature that goes beyond Dicke’s model. Finally, we measure the ${g}{N}^{(2)}({t}{1},{t}_{2})$ at different times and observe the appearance of anticorrelations during the pulse that are not present when starting from a steady state.
Phys. Rev. Lett. 134, 153602 (2025)
Atomic & molecular processes in external fields, Atomic gases, Cooling & trapping, Fluorescence spectroscopy, Optical lattices & traps, Photon counting, Resonance fluorescence
Giant Nonreciprocity and Gyration through Modulation-Induced Hatano-Nelson Coupling in Integrated Photonics
Research article | Non-reciprocal propagation | 2025-04-15 06:00 EDT
Oğulcan E. Örsel, Jiho Noh, Penghao Zhu, Jieun Yim, Taylor L. Hughes, Ronny Thomale, and Gaurav Bahl
Dynamically tuning light flow in tiny optical circuits enables precise control over how light moves between them.
Phys. Rev. Lett. 134, 153801 (2025)
Non-reciprocal propagation, Non-reciprocal transmission, Nonlinear optics, Optical materials & elements, Photonics
Electron-Only Magnetic Reconnection and Inverse Magnetic-Energy Transfer at Subion Scales
Research article | Magnetic reconnection | 2025-04-15 06:00 EDT
Zhuo Liu, Caio Silva, Lucio M. Milanese, Muni Zhou, Noah R. Mandell, and Nuno F. Loureiro
We derive, and validate numerically, an analytical model for electron-only magnetic reconnection applicable to strongly magnetized plasmas. Our model predicts subion-scale reconnection rates significantly higher than those pertaining to large-scale reconnection, aligning with recent observations and simulations. We apply this reconnection model to the problem of inverse magnetic energy transfer at subion scales. We derive time-dependent scaling laws for the magnetic energy decay and the typical magnetic structure dimensions that differ from those previously found in the magnetohydrodynamics regime. These scaling laws are validated via two- and three-dimensional simulations, demonstrating that subion-scale magnetic fields can reach large, system-size scales via successive coalescence.
Phys. Rev. Lett. 134, 155201 (2025)
Magnetic reconnection, Plasma turbulence, Space & astrophysical plasma, Gyrofluid & gyrokinetics
Hydrodynamic Modes and Operator Spreading in a Long-Range Center-of-Mass-Conserving Brownian Sachdev-Ye-Kitaev Model
Research article | Quantum chaotic transport | 2025-04-15 06:00 EDT
Bai-Lin Cheng, Shao-Kai Jian, and Zhi-Cheng Yang
We study a center-of-mass-conserving Brownian complex Sachdev-Ye-Kitaev model with long-range (power-law) interactions characterized by $1/{r}^{\eta }$. The kinetic constraint and long-range interactions conspire to yield rich hydrodynamics associated with the conserved charge, which we reveal by computing the Schwinger-Keldysh effective action. Our result shows that charge transport in this system can be subdiffusive, diffusive, or superdiffusive, with the dynamical exponent controlled by $\eta $. We further employ a doubled Hilbert space methodology to derive an effective action for the out-of-time-order correlator, from which we obtain the phase diagram delineating regimes where the light cone is linear or logarithmic. Our results provide a concrete example of a quantum many-body system with kinetic constraint and long-range interactions in which the emergent hydrodynamic modes and out-of-time-order correlator can be computed analytically.
Phys. Rev. Lett. 134, 156301 (2025)
Quantum chaotic transport, Quantum transport, Nonequilibrium systems, Quantum many-body systems, Brownian dynamics, Nonequilibrium Green’s function, Sachdev-Ye-Kitaev model
Non-Hermitian Topology in Multiterminal Superconducting Junctions
Research article | Andreev bound states | 2025-04-15 06:00 EDT
David Christian Ohnmacht, Valentin Wilhelm, Hannes Weisbrich, and Wolfgang Belzig
Recent experimental advancements in dissipation control have yielded significant insights into non-Hermitian Hamiltonians for open quantum systems. Of particular interest are the topological characteristics exhibited by these non-Hermitian systems, that arise from exceptional points—distinct degeneracies unique to such systems. In this Letter, we focus on Andreev bound states in multiterminal Josephson junctions with non-Hermiticity induced by normal metal or ferromagnetic leads. By investigating several systems of different synthetic dimensions and symmetries, we predict fragile and stable non-Hermitian topological phases in these engineered superconducting systems.
Phys. Rev. Lett. 134, 156601 (2025)
Andreev bound states, Superconductivity, Topological phases of matter, Exceptional points, Josephson junctions, Non-Hermitian systems, Green’s function methods, Methods in superconductivity, Symmetries in condensed matter, Topology
Magnetic Vortex Dynamics Probed by Time-Resolved Magnetic Helicoidal Dichroism
Research article | Light-matter interaction | 2025-04-15 06:00 EDT
Mauro Fanciulli, Matteo Pancaldi, Anda-Elena Stanciu, Matthieu Guer, Emanuele Pedersoli, Dario De Angelis, Primož Rebernik Ribič, David Bresteau, Martin Luttmann, Pietro Carrara, Arun Ravindran, Benedikt Rösner, Christian David, Carlo Spezzani, Michele Manfredda, Ricardo Sousa, Laurent Vila, Ioan Lucian Prejbeanu, Liliana D. Buda-Prejbeanu, Bernard Dieny, Giovanni De Ninno, Flavio Capotondi, Thierry Ruchon, and Maurizio Sacchi
Time-resolved magnetic helicoidal dichroism reveals transient changes in spin texture not seen with x-ray magnetic circular dichroism.
Phys. Rev. Lett. 134, 156701 (2025)
Light-matter interaction, Magnetic vortices, Structured light, Ultrafast magnetization dynamics, Classical electromagnetism, Magnetization measurements, Time-resolved light scattering spectroscopy, X-ray scattering
Nonequilibrium Fluctuation-Response Relations: From Identities to Bounds
Research article | Fluctuation-dissipation theorem | 2025-04-15 06:00 EDT
Timur Aslyamov, Krzysztof Ptaszyński, and Massimiliano Esposito
Exact fluctuation response relations that generalize the fluctuation-dissipation theorem and unify it with the thermodynamic uncertainty relation (TUR) prove and extend the recently conjectured response-TUR.
Phys. Rev. Lett. 134, 157101 (2025)
Fluctuation-dissipation theorem, Fluctuations & noise, Nonequilibrium statistical mechanics, Stochastic thermodynamics, Linear response theory
Micromechanical Origin of Rate Independence of the Stress in Sheared Granular Materials
Research article | Friction | 2025-04-15 06:00 EDT
Ravi Gautam and Prabhu R. Nott
The stress in slowly sheared granular materials is independent of the shear rate, but individual particles transmit momentum at a rate proportional to the shear rate. How a rate-dependent microscopic momentum flux leads to a rate-independent macroscopic stress is a fundamental, unanswered question. Another prominent feature is the occurrence of large stress fluctuations. Here, we show that the two features are closely related. The fluctuations arise from recurrent jamming-yielding dynamics, with deformation being elastic in the jammed phases and yielding occurring in short bursts. These findings lead to an explanation for the rate independence of the stress.
Phys. Rev. Lett. 134, 158201 (2025)
Friction, Granular flows, Granular materials, Rheology
Myosin-Independent Amoeboid Cell Motility
Research article | Cell locomotion | 2025-04-15 06:00 EDT
Winfried Schmidt, Walter Zimmermann, Chaouqi Misbah, and Alexander Farutin
Mammalian cell polarization and motility are important processes involved in many physiological and pathological phenomena, such as embryonic development, wound healing, and cancer metastasis. The traditional view of mammalian cell motility suggests that molecular motors, adhesion, and cell deformation are all necessary components for mammalian cell movement. However, experiments on immune system cells have shown that the inhibition of molecular motors does not significantly affect cell motility. We present a new theory and simulations demonstrating that actin polymerization alone is sufficient to induce spontaneously cell polarity accompanied by the retrograde flow. These findings provide a new understanding of the fundamental mechanisms of cell movement and at the same time provide a simple mechanism for cell motility in diverse configurations, e.g., on an adherent substrate, in a nonadherent matrix, or in liquids.
Phys. Rev. Lett. 134, 158301 (2025)
Cell locomotion, Living matter & active matter, Microswimmers
Local Clustering and Global Spreading of Receptors for Optimal Spatial Gradient Sensing
Research article | Biological information processing | 2025-04-15 06:00 EDT
Albert Alonso, Robert G. Endres, and Julius B. Kirkegaard
Spatial information from cell-surface receptors is crucial for processes that require signal processing and sensing of the environment. Here, we investigate the optimal placement of such receptors through a theoretical model that minimizes uncertainty in gradient estimation. Without requiring a priori knowledge of the physical limits of sensing or biochemical processes, we reproduce the emergence of clusters that closely resemble those observed in real cells. On perfect spherical surfaces, optimally placed receptors spread uniformly. When perturbations break their symmetry, receptors cluster in regions of high curvature, massively reducing estimation uncertainty. This agrees in many scenarios with mechanistic models that minimize elastic preference discrepancies between receptors and cell membranes. We further extend our model to motile receptors responding to cell-shape changes and external fluid flow, demonstrating the biological relevance of our model. Our findings provide a simple and utilitarian explanation for receptor clustering at high-curvature regions when high sensing accuracy is paramount.
Phys. Rev. Lett. 134, 158401 (2025)
Biological information processing, Biomolecular & subcellular processes, Chemotaxis, Stochastic inference, Cells, Information theory, Stochastic analysis
Physical Review X
Deep-Learning Generation of High-Resolution Images of Live Cells in Culture Using Tri-Frequency Acoustic Images
Research article | Acoustic measurements | 2025-04-15 06:00 EDT
Natsumi Fujiwara, Midori Uno, Hiroki Fukuda, Akira Nagakubo, Shao Ying Tan, Masahiro Kino-oka, and Hirotsugu Ogi
A new method for obtaining high-resolution images of cells from low-resolution ultrasound data enables longer, noninvasive monitoring of organisms.
Phys. Rev. X 15, 021015 (2025)
Acoustic measurements, Deep learning, Super-resolution techniques
Topology of Discrete Quantum Feedback Control
Research article | Open quantum systems | 2025-04-15 06:00 EDT
Masaya Nakagawa and Masahito Ueda
A new class of dynamical topological phases emerges in quantum systems where measurements and feedback control shape evolution. This discovery enables noiseresistant quantum control and advances the study of topology in open quantum systems.
Phys. Rev. X 15, 021016 (2025)
Open quantum systems, Quantum control, Quantum feedback, Topological phases of matter, Nonequilibrium systems
arXiv
Stochastic Thermodynamics of Non-reciprocally Interacting Particles and Fields
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-04-16 20:00 EDT
Atul Tanaji Mohite, Heiko Rieger
Nonreciprocal interactions that violate Newton’s law ‘actio=reactio’ are ubiquitous in nature and are currently intensively investigated in active matter, chemical reaction networks, population dynamics, and many other fields. An outstanding challenge is the thermodynamically consistent formulation of the underlying stochastic dynamics that obeys local detailed balance and allows for a rigorous analysis of the stochastic thermodynamics of non-reciprocally interacting particles. Here, we present such a framework for a broad class of active systems and derive by systematic coarse-graining exact expressions for the macroscopic entropy production. Four independent contributions to the thermodynamic dissipation can be identified, among which the energy flux sustaining vorticity currents manifests the presence of non-reciprocal interactions. Then, Onsager’s non-reciprocal relations, the fluctuation-response relation, the fluctuation relation and the thermodynamic uncertainty relations for non-reciprocal systems are derived. Finally, we demonstrate that our general framework is applicable to a plethora of active matter systems and chemical reaction networks and opens new paths to understand the stochastic thermodynamics of non-reciprocally interacting many-body systems.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
Cat states carrying long-range correlations in the many-body localized phase
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-04-16 20:00 EDT
Nicolas Laflorencie, Jeanne Colbois, Fabien Alet
Despite considerable efforts over the last decade, the high-energy phase diagram of the random-field Heisenberg chain still eludes our understanding, in particular the nature of the non-ergodic many-body localized (MBL) regime expected at strong disorder. In this work, we revisit this paradigmatic model by studying the statistics of rare atypical events of strongly correlated spin pairs traversing the entire system. They occur for unexpectedly strong disorder, i.e., in a regime where standard estimates fail to detect any instability. We then identify these very peculiar high-energy eigenstates, which exhibit system-wide $ {\cal{O}}(1)$ correlations, as nearly degenerate pairs of resonant cat states of the form $ |{\Phi}_{\pm}\rangle\sim {|{\alpha_1}\rangle}\pm {|{\alpha_2}\rangle}$ , where $ {|{\alpha_1}\rangle}$ and $ {|{\alpha_2}\rangle}$ are spin basis states. We propose a simple and generic analytical description of this new class of eigenstates that exhibit system-spanning entanglement. This analytical ansatz guides us in our search for rare hidden cat states in exponentially large many-body spectra. This also enables a systematic numerical inspection of the microscopic anatomy of these unconventional pairs, which appear in a wide range of disorder strengths. In the light of recent studies and ongoing debates on the MBL problem, our results offer new perspectives and stimulating challenges to this very active field.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
26 pages, 18+6 figures
Non-Hermitian Multipole Skin Effects Challenge Localization
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-04-16 20:00 EDT
Jacopo Gliozzi, Federico Balducci, Taylor L. Hughes, Giuseppe De Tomasi
We study the effect of quenched disorder on the non-Hermitian skin effect in systems that conserve a U(1) charge and its associated multipole moments. In particular, we generalize the Hatano-Nelson argument for an Anderson transition in a disordered system with non-reciprocal hopping to the interacting case. When only U(1) charge is conserved, we show that there is a transition between a skin effect phase, in which charges are localized at a boundary, and a many-body localized phase, in which the charges are localized at random positions. In periodic boundary conditions, the skin effect gives way to a delocalized phase with a unidirectional current. If additional multipole moments like dipoles are conserved, we show that the non-Hermitian skin effect remains stable for any amount of disorder. As a result, under periodic boundary conditions, the system is always delocalized regardless of disorder strength.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
5+3 pages, 4+2 figures
Magnetically modified double slit based x-ray interferometry
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
S. Atkar, Z. Tumbleson, S. A. Morley, N. Burdet, A. Islegen-Wojdyla, K. A. Goldberg, A. Scholl, S. A. Montoya, Trinanjan Datta, S. Roy
We demonstrate an experimental approach to determine magneto-optical effects which combines x-ray magnetic circular dichroism (XMCD) with x-ray interferometry, based on the concepts of Young’s canonical double slit. By covering one of two slits with a magnetic thin film and employing XMCD, we show that it is possible to determine both the real and the imaginary parts of the complex refractive index by measuring the fringe shifts that occur due to a change in the sample magnetization. Our hybrid spectroscopic-interferometric methodology provides a means to probe changes in the magnetic refractive index in terms of the electron spin moment.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 8 figures
Development of microwave surface elastoresistivity measurement technique under tunable strain
New Submission | Superconductivity (cond-mat.supr-con) | 2025-04-16 20:00 EDT
Suguru Hosoi, Kohei Matsuura, Masaaki Shimozawa, Koichi Izawa, Shigeru Kasahara, Takasada Shibauchi
By integrating a dielectric microwave resonator with a piezoelectric-based strain device, we develop an in situ strain-tunable microwave spectroscopy technique that enables contactless measurements of superconducting properties under strain. In the slightly overdoped iron-based superconductor BaFe$ _2$ (As$ _{1-x}$ P$ _x$ )$ 2$ , we successfully observe a systematic strain dependence of the superconducting transition, manifested as changes in the quality factor and resonance frequency shifts. Both compressive and tensile anisotropic lattice distortions along the [110]$ {{\rm T}}$ direction suppress superconductivity, consistent with standard transport measurements, highlighting the pivotal role of nematic fluctuations in the superconducting mechanism. Our strain-tunable cavity therefore serves as a powerful, contactless probe of fundamental superconducting material properties under strain and may also potentially facilitate the design of hybrid quantum systems with strain-controlled quantum degrees of freedom.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
5 pages 5 figures
MatterTune: An Integrated, User-Friendly Platform for Fine-Tuning Atomistic Foundation Models to Accelerate Materials Simulation and Discovery
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Lingyu Kong, Nima Shoghi, Guoxiang Hu, Pan Li, Victor Fung
Geometric machine learning models such as graph neural networks have achieved remarkable success in recent years in chemical and materials science research for applications such as high-throughput virtual screening and atomistic simulations. The success of these models can be attributed to their ability to effectively learn latent representations of atomic structures directly from the training data. Conversely, this also results in high data requirements for these models, hindering their application to problems which are data sparse which are common in this domain. To address this limitation, there is a growing development in the area of pre-trained machine learning models which have learned general, fundamental, geometric relationships in atomistic data, and which can then be fine-tuned to much smaller application-specific datasets. In particular, models which are pre-trained on diverse, large-scale atomistic datasets have shown impressive generalizability and flexibility to downstream applications, and are increasingly referred to as atomistic foundation models. To leverage the untapped potential of these foundation models, we introduce MatterTune, a modular and extensible framework that provides advanced fine-tuning capabilities and seamless integration of atomistic foundation models into downstream materials informatics and simulation workflows, thereby lowering the barriers to adoption and facilitating diverse applications in materials science. In its current state, MatterTune supports a number of state-of-the-art foundation models such as ORB, MatterSim, JMP, and EquformerV2, and hosts a wide range of features including a modular and flexible design, distributed and customizable fine-tuning, broad support for downstream informatics tasks, and more.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI), Machine Learning (cs.LG)
Out-of-equilibrium dynamics across the first-order quantum transitions of one-dimensional quantum Ising models
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-04-16 20:00 EDT
Andrea Pelissetto, Davide Rossini, Ettore Vicari
We study the out-of-equilibrium dynamics of one-dimensional quantum Ising models in a transverse field $ g$ , driven by a time-dependent longitudinal field $ h$ across their {\em magnetic} first-order quantum transition at $ h=0$ , for sufficiently small values of $ |g|$ . We consider nearest-neighbor Ising chains of size $ L$ with periodic boundary conditions. We focus on the out-of-equilibrium behavior arising from Kibble-Zurek protocols, in which $ h$ is varied linearly in time with time scale $ t_s$ , i.e., $ h(t)=t/t_s$ . The system starts from the ground state at $ h_i\equiv h(t_i)<0$ , where the longitudinal magnetization $ M$ is negative. Then it evolves unitarily up to positive values of $ h(t)$ , where $ M(t)$ becomes eventually positive. We identify several scaling regimes characterized by a nontrivial interplay between the size $ L$ and the time scale $ t_s$ , which can be observed when the system is close to one of the many avoided level crossings that occur for $ h\ge 0$ . In the $ L\to\infty$ limit, all these crossings approach $ h=0^+$ , making the study of the thermodynamic limit, defined as the limit $ L\to\infty$ keeping $ t$ and $ t_s$ constant, problematic. We study such limit numerically, by first determining the large-$ L$ quantum evolution at fixed $ t_s$ , and then analyzing its behavior with increasing $ t_s$ . Our analysis shows that the system switches from the initial state with $ M<0$ to a positively magnetized state at $ h = h_\ast(t_s)>0$ , where $ h_\ast(t_s)$ decreases with increasing $ t_s$ , apparently as $ h_\ast\sim 1/\ln t_s$ . This suggests the existence of a scaling behavior in terms of the rescaled time $ \Omega = t \ln t_s/t_s$ . The numerical results also show that the system converges to a nontrivial stationary state in the large-$ t$ limit, characterized by an energy significantly larger than that of the corresponding homogeneously magnetized ground state.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
21 pages, 14 figs
Grain Boundary Space Charge Engineering of Solid Oxide Electrolytes: Model Thin Film Study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Thomas Defferriere, Yong Beom Kim, Colin Gilgenbach, James M. LeBeau, WooChul Jung, Harry L. Tuller
Grain boundaries (GB) profoundly influence the electrical properties of polycrystalline ionic solids. Yet, precise control of their transport characteristics has remained elusive, thereby limiting the performance of solid-state electrochemical devices. Here, we demonstrate unprecedented manipulation of space charge controlled ionic grain boundary resistance (up to 12 orders of magnitude) in metal oxide thin films. We exploit the orders of magnitude higher grain boundary diffusivities of substrate cation elements (i.e. Al from $ Al_2O_3$ and Mg from MgO) relative to the bulk to modify the grain boundary chemistry, and thereby GB core charge, in a model oxygen ion conducting polycrystalline thin film solid electrolyte, Gd-doped $ CeO_2$ . This approach, confirmed jointly by TEM imaging and by extracting the respective GB and bulk diffusivities from measured SIMS profiles, enabled us to selectively control the chemistry of the GBs, while minimally modifying grain (bulk) chemistry or film microstructure, thereby ruling out potential effects of microstructure, strain or secondary phases. Broad tuning of GB space charge potentials is achieved by manipulating GB core charge density by over an order of magnitude, thereby providing a powerful tool for systematic studies of grain boundary phenomena across various functional materials. The implications of such control are far-reaching in achieving new functionality, improving efficiency and longevity of solid-state electrochemical devices.
Materials Science (cond-mat.mtrl-sci)
Biomechanics of orientationally ordered epithelial tissue
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-04-16 20:00 EDT
Patrick W. Alford, Luiza Angheluta, Jorge Vinals
Organogenesis involves large deformations and complex shape changes that require elaborate mechanical regulation. Models of tissue biomechanics have been introduced to account for the coupling between mechanical response and biochemical processes. Recent experimental evidence indicates that the mechanical response of epithelial tissue is strongly anisotropic, with the degree of anisotropy being correlated with the existence of long range orientational order of cytoskeletal organization across the tissue. A theoretical framework is introduced that captures the dynamic feedback between tissue elastic response and cytoskeletal reorganization under stress. Within the linear regime for small and uniform applied strains, the shear modulus is effectively reduced by the nematic order in cytoskeletal alignment induced by the applied strain. This prediction agrees with experimental observations of epithelial response in lithographically patterned micro tissues.
Soft Condensed Matter (cond-mat.soft), Tissues and Organs (q-bio.TO)
Shuttling Majorana zero modes in disordered and noisy topological superconductors
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Bill P. Truong, Kartiek Agarwal, T. Pereg-Barnea
The braiding of Majorana zero modes (MZMs) forms the fundamental building block for topological quantum computation. Braiding protocols which involve the physical exchange of MZMs are typically envisioned on a network of topological superconducting wires. An essential component of these protocols is the transport of MZMs, which can be performed by using electric gates to locally tune sections (“piano keys”) of the wire between topologically trivial and non-trivial phases. In this work, we numerically simulate this piano key transport on a superconducting wire which contains either disorder (uncorrelated and correlated) or noise. We focus on the impact of these additional effects on the diabatic error, which describes unwanted transitions between the ground state and excited states. For disorder, we show that the behavior of the average diabatic error is predominantly controlled by the statistics of the minimum bulk energy gap. When the disorder is spatially correlated, we demonstrate that this leads to an increase in the diabatic error due to a further suppression of the minimum bulk energy gap and highlight the scaling of this suppression with the piano key size. For noise, we illustrate that the diabatic error is significantly enhanced due to optical transitions which depend on the minimum bulk energy gap as well as the frequency modes present in the noise. The results presented here serve to further characterize the diabatic error in disordered and noisy settings, which are important considerations in practical implementations of physical braiding schemes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
18 pages, 9 figures
Adaptive Synaptogenesis Implemented on a Nanomagnetic Platform
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-04-16 20:00 EDT
Faiyaz Elahi Mullick, Supriyo Bandyopadhyay, Rob Baxter, Tony J. Ragucci, Avik W. Ghosh
The human brain functions very differently from artificial neural networks (ANN) and possesses unique features that are absent in ANN. An important one among them is “adaptive synaptogenesis” that modifies synaptic weights when needed to avoid catastrophic forgetting and promote lifelong learning. The key aspect of this algorithm is supervised Hebbian learning, where weight modifications in the neocortex driven by temporal coincidence are further accepted or vetoed by an added control mechanism from the hippocampus during the training cycle, to make distant synaptic connections highly sparse and strategic. In this work, we discuss various algorithmic aspects of adaptive synaptogenesis tailored to edge computing, demonstrate its function using simulations, and design nanomagnetic hardware accelerators for specific functions of synaptogenesis.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Neural and Evolutionary Computing (cs.NE), Systems and Control (eess.SY)
Ground-State-Based Model Reduction with Unitary Circuits
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Shengtao Jiang, Steven R. White
We present a method to numerically obtain low-energy effective models based on a unitary transformation of the ground state. The algorithm finds a unitary circuit that transforms the ground state of the original model to a projected wavefunction with only the low-energy degrees of freedom. The effective model can then be derived using the unitary transformation encoded in the circuit. We test our method on the one-dimensional and two-dimensional square-lattice Hubbard model at half-filling, and obtain more accurate effective spin models than the standard perturbative approach.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
5 pages, 4 figures; comments are welcome
Non-resonant two-photon x-ray absorption in Cu
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
J. J. Kas, J. J. Rehr, J. Stohr, J. Vinson
We present a real-space Green’s function theory and calculations of two-photon x-ray absorption (TPA). Our focus is on non-resonant K-shell TPA in metallic Cu, which has been observed experimentally at intense x-ray free electron laser (XFEL) sources. The theory is based on an independentparticle Green’s function treatment of the Kramers-Heisenberg equation and an approximation for the sum over non-resonant intermediate states in terms of a static quadrupole transition operator. XFEL effects are modeled by a partially depleted d-band. This approach is shown to give results for K-shell TPA in quantitative agreement with XFEL experiment and with a Bethe-Salpeter Equation approach. We also briefly discuss many-body corrections and TPA sum-rules.
Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 4 figures
Gapless Foliated-Exotic Duality
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Kantaro Ohmori, Shutaro Shimamura
In this work, we construct a new foliated quantum field theory equivalent to the exotic $ \phi$ -theory – a fractonic gapless scalar field theory described by tensor gauge fields and exhibiting $ U(1) \times U(1)$ subsystem global symmetry. This subsystem symmetry has an ‘t Hooft anomaly, which is captured by a subsystem symmetry-protected topological (SSPT) phase in one dimension higher via the anomaly inflow mechanism. By analyzing both the anomaly inflow structure and the foliated-exotic duality in the SSPT phases, we establish the foliated-exotic duality in the $ \phi$ -theories. Furthermore, we also investigate the foliated-exotic duality in the $ \hat\phi$ -theory, which is dual to the $ \phi$ -theory, and construct the foliated $ \hat\phi$ -theory. These are the first examples of the foliated-exotic duality in gapless theories.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th)
59 pages, 1 figure
Elastocaloric signature of the excitonic instability in Ta$_2$NiSe$_5$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Elliott Rosenberg, Joss Ayres-Sims, Andrew Millis, David Cobden, Jiun-Haw Chu
On cooling through a temperature $ T_S$ of around 324 K, Ta$ _2$ NiSe$ _5$ undergoes a transition from a semimetallic state to one with a gapped electronic spectrum which is suspected to be an excitonic insulator. However, at this transition the structure also changes, from orthorhombic to monoclinic, leaving open the question of whether it is driven primarily by excitonic ordering or by a lattice instability. A lattice instability of this symmetry would correspond to softening of a B$ _{2g}$ optical or acoustic phonon mode. Here, we report that elastocaloric measurements of Ta$ _2$ NiSe$ _5$ with induced B$ _{2g}$ strain reveal a thermodynamic susceptibility described by a Curie-Weiss law with a Curie temperature $ T^\ast$ of 298 K. The fact that $ T^\ast$ is close to $ T_S$ rules out the possibility that the B$ _{2g}$ acoustic mode is responsible for the transition. Since prior Raman measurements have shown minimal softening of the B$ _{2g}$ optical mode as well, our finding strengthens the case that the transition is largely excitonic in nature. Our work underscores the potential of using strain as a tool for separating electronic and lattice contributions in phase transitions.
Strongly Correlated Electrons (cond-mat.str-el)
XRD study of the magnetization plateau above 40 T in the frustrated helimagnet CuGaCr${4}$S${8}$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
M. Gen, K. Noda, K. Shimbori, T. Tanaka, D. Bhoi, K. Seki, H. Kobayashi, K. Gautam, M. Akaki, Y. Ishii, Y. H. Matsuda, Y. Kubota, Y. Inubushi, M. Yabashi, Y. Kohama, T. Arima, A. Ikeda
CuGaCr$ _{4}$ S$ _{8}$ , which contains a chromium breathing pyrochlore network, exhibits diverse magnetic phases, including an incommensurate helical state below 31 K and a 1/2-magnetization plateau above 40 T, owing to the interplay between magnetic frustration and spin-lattice coupling. Here, we perform a single-shot powder x-ray diffraction experiment on CuGaCr$ _{4}$ S$ _{8}$ in a pulsed high magnetic field of 55 T, revealing an orthorhombic-to-cubic (or pseudocubic) structural transition upon entering the 1/2-magnetization plateau phase at low temperatures. This observation suggests the emergence of a commensurate ferrimagnetic order, where a 3-up-1-down spin configuration is realized in each small tetrahedron, and the all-up or all-down in each large tetrahedron. We propose two types of 16-sublattice magnetic structures, which are degenerate within exchange interactions between the first, second, and third nearest neighbors.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 7 figures, 2 tables
Intertwined fluctuations and isotope effects in the Hubbard-Holstein model on the square lattice from functional renormalization
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Aiman Al-Eryani, Sabine Andergassen, Michael M. Scherer
Electron-electron and electron-phonon interactions are responsible for the formation of spin, charge, and superconducting correlations in layered quantum materials. A paradigmatic model for such materials that captures both kinds of interactions is the two-dimensional Hubbard-Holstein model with a dispersionless Einstein phonon. In this work, we provide a detailed analysis of the magnetic, density, and superconducting fluctuations at and away from half-filling. To that end, we employ the functional renormalization group using the recently introduced extension of the single-boson exchange formulation. More precisely, we go beyond previous approaches to the model by resolving the full frequency dependence of the two-particle vertex and taking into account the feedback from the electronic self-energy. We perform broad parameter scans in the space of Hubbard repulsion, electron-phonon coupling strength, and phonon frequency to explore the leading magnetic, density, and superconducting susceptibilities from the adiabatic to the anti-adiabatic regime. Our numerical data reveal that self-energy effects lead to an enhancement of the $ d$ -wave superconducting susceptibility towards larger phonon frequencies, in contrast to earlier isotope-effect studies. At small phonon frequencies, large density contributions to the $ s$ -wave superconducting susceptibility change sign and eventually lead to a reduction of $ s$ -wave superconductivity with increasing electron-phonon coupling, signaling the breakdown of Migdal-Eliashberg theory. We analyze our findings systematically, employing detailed diagnostics of the intertwined fluctuations and pinning down the various positive and negative isotope effects of the physical susceptibilities.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
33 pages, 24 figures; comments welcome
Strain effect on optical properties and quantum weight of 2D magnetic topological insulators MnBi$_2$X$_4$ (X = Te, Se, S)
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Nguyen Tuan Hung, Vuong Van Thanh, Mingda Li, Takahiro Shimada
Manipulating the optical and quantum properties of two-dimensional (2D) materials through strain engineering is not only fundamentally interesting but also provides significant benefits across various applications. In this work, we employ first-principles calculations to investigate the effects of strain on the magnetic and optical properties of 2D topological insulators MnBi$ _2$ X$ _4$ (X = Te, Se, S). Our results indicate that biaxial strain enhances the Mn magnetic moment, while uniaxial strains reduce it. Significantly, the strain-dependent behavior, quantified through the quantum weight, can be leveraged to control the system’s quantum geometry and topological features. Particularly, uniaxial strains reduce the quantum weight and introduce anisotropy, thus providing an additional degree of freedom to tailor device functionalities. Finally, by analyzing chemical bonds under various strain directions, we elucidate how the intrinsic ductile or brittle fracture behavior of MnBi$ _2$ X$ _4$ could impact fabrication protocols and structural stability. These insights pave the way for strain-based approaches to optimize the quantum properties in 2D magnetic topological insulators in practical device contexts.
Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
3 figures, 1 table
Unusual gas sensor response and semiconductor-to-insulator transition in WO3-x nanostructures : The role of oxygen vacancy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
WO3-x thinfilms featuring petal-like and lamella-like nanostructures are grown under controlled oxygen partial pressures using hot filament chemical vapor deposition. These synthesized WO3-x nanostructures exhibit monoclinic structure and contain a significant amount of oxygen vacancies (VO) as confirmed by X-ray diffraction and Raman spectroscopy, respectively. These WO3-x nanostructures demonstrate sensor response to both NH3 and NO2 gases even at room temperature. However, the sensor response varies with temperature and analyte gas type. For NH3, the sensors exhibit an increase in resistance behaving like a p-type semiconductor at temperatures below 150 0C while the resistance decreases at higher temperatures, resembling n-type semiconductor behavior. On the other hand, below 150 0C, these sensors display n-type behavior towards NO2 but act like p-type semiconductor at higher temperatures. Further temperature dependent transport studies were performed in these WO3-x nanostructures in the temperature range from 25 to 300 oC, after inducing additional VO in the films through annealing under CH4. The petal-like WO3-x nanostructures display an abrupt change in resistance, indicating insulator-to-semiconductor and semiconductor-to-insulator transitions during heating and cooling cycles respectively, in the temperature range of 100 - 212 0C. In lamella-like WO3-x nanostructures, the resistance is flipped from semiconductor-to-insulator at 300 0C and remains insulating state when cooled down to 30 0C. The abnormal gas sensing behavior and insulator - semiconductor transition is discussed in terms of VO in WO3-x nanostructures.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
26 pages, 9 figures; Accepted in Surfaces and Interfaces (2025)
Infinite temperature spin dynamics in the asymmetric Hatsugai-Kohmoto model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Ádám Bácsi, Doru Sticlet, Catalin Pascu Moca, Balázs Dóra
We focus on the infinite temperature dynamical spin structure factor of the asymmetric Hatsugai-Kohmoto model, the relative of the asymmetric Hubbard model. It is characterized by distinct single particle energies for the two spin species, which interact with each other through a contact interaction in momentum space. We evaluate its spin structure factor exactly and follow the evolution of its excitation spectrum for all fillings and interactions, identify signatures of the Mott transition and fingerprints of the asymmetric hoppings. The longitudinal spin structure factor exhibits sound like and interaction induced gapped excitations, whose number gets doubled in the presence of hopping asymmetry. The transverse response displays the competition of interaction and asymmetry induced gaps and results in a quadratic excitation branch at their transition. The complete asymmetric case features momentum-independent dynamical structure factor, characteristic to transitions involving a flat band.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech)
6 pages, 2 figures
Raman Fingerprints of Phase Transitions and Ferroic Couplings in Van der Waals Material CuCrP$_2$S$_6$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Jing Tang, Benjamin J Lawrie, Mouyang Cheng, Yueh-Chun Wu, Huan Zhao, Dejia Kong, Ruiqi Lu, Ching-Hsiang Yao, Zheng Gai, An-Ping Li, Mingda Li, Xi Ling
CuCrP$ _2$ S$ _6$ (CCPS), a type-II multiferroic material, exhibits unique phase transitions involving ferroelectric, antiferroelectric, and antiferromagnetic ordering. In this study, we conduct a comprehensive investigation on the intricate phase transitions and their multiferroic couplings in CCPS across a wide temperature range from 4 to 345 K through Raman spectroscopic measurements down to 5 cm$ ^{-1}$ . We first assign the observed Raman modes with the support of theoretical calculations and angle-resolved polarized Raman measurements. We further present clear signatures of phase transitions from analyses of temperature-dependent Raman spectral parameters. Particularly, two low-frequency soft modes are observed at 36.1 cm$ ^{-1}$ and 70.5 cm$ ^{-1}$ below 145 K, indicating the antiferroelectric to quasi-antiferroelectric transition. Moreover, phonon modes hardening is observed when the temperature increases from 4 to 65 K, suggesting negative thermal expansion (NTE) and strong magnetoelastic coupling below 65 K. These findings advance the understanding of vdW multiferroic CCPS, paving the way for future design and engineering of multiferroicity in cutting-edge technologies, such as spintronics and quantum devices.
Materials Science (cond-mat.mtrl-sci)
22 pages, 5 figures
Superconducting quantum oscillations and anomalous negative magnetoresistance in a honeycomb nanopatterned oxide interface superconductor
New Submission | Superconductivity (cond-mat.supr-con) | 2025-04-16 20:00 EDT
Yishuai Wang, Siyuan Hong, Wenze Pan, Yi Zhou, Yanwu Xie
The extremely low superfluid density and unprecedented tunability of oxide interface superconductors provide an ideal platform for studying fluctuations in two-dimensional superconductors. In this work, we have fabricated a LaAlO3/KTaO3 interface superconductor patterned with a nanohoneycomb array of insulating islands. Little-Parks-like magnetoresistance oscillations have been observed, which are dictated by the superconducting flux quantum h/2e. Moreover, an anomalous negative magnetoresistance (ANMR) appears under a weak magnetic field, suggesting magnetic-field-enhanced superconductivity. By examining their dependences on temperature, measurement current, and electrical gating, we conclude that both phenomena are associated with superconducting order parameter: The h/2e oscillations provide direct evidence of Cooper pair transport; the ANMR is interpreted as a consequence of multiple connected narrow superconducting paths with strong fluctuations.
Superconductivity (cond-mat.supr-con)
Physical Review X 15, 011006 (2025)
douka: A universal platform of data assimilation for materials modeling
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Aoi Watanabe, Ryuhei Sato, Ikuya Kinefuchi, Yasushi Shibuta
A large-scale, general-purpose data assimilation (DA) platform for materials modeling, douka, was developed and applied to nonlinear materials models. The platform demonstrated its effectiveness in estimating physical properties that cannot be directly obtained from observed data. DA was successfully performed using experimental images of oxygen evolution reaction at a water electrolysis electrode, enabling the estimation of oxygen gas injection velocity and bubble contact angle. Furthermore, large-scale ensemble DA was conducted on the supercomputer Fugaku, achieving state estimation with up to 8,192 ensemble members. The results confirmed that runtime scaling for the prediction step follows the weak scaling law, ensuring computational efficiency even with increased ensemble sizes. These findings highlight the potential of douka as a new approach for data-driven materials science, integrating experimental data with numerical simulation.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
47 pages, 16 figures
Symmetry-protected topological order identified via Gutzwiller-guided density-matrix-renormalization-group: $\mathrm{SO}(n)$ spin chains
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Pei-Yuan Cai, Hui-Ke Jin, Yi Zhou
We present a comprehensive study of topological phases in the SO($ n$ ) spin chains using a combination of analytical parton construction and numerical techniques. For even $ n=2l$ , we identify a novel SPT$ ^2$ phase characterized by two distinct topological sectors, exhibiting exact degeneracy at the matrix product state (MPS) exactly solvable point. Through Gutzwiller-projected mean-field theory and density matrix renormalization group (DMRG) calculations, we demonstrate that these sectors remain topologically degenerate throughout the SPT$ ^2$ phase, with energy gaps decaying exponentially with system size. For odd $ n=2l+1$ , we show that the ground state remains unique. We precisely characterize critical states using entanglement entropy scaling, confirming the central charges predicted by conformal field theories. Our results reveal fundamental differences between even and odd $ n$ cases, provide numerical verification of topological protection, and establish reliable methods for studying high-symmetry quantum systems. The Gutzwiller-guided DMRG is demonstrated to be notably efficient in targeting specific topological sectors.
Strongly Correlated Electrons (cond-mat.str-el)
Induced magnetic moment at two-dimensional MXene/ferromagnetic interface evaluated by angle-dependent hard X-ray photoemission spectroscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Prabhat Kumar, Shunsuke Tsuda, Koichiro Yaji, Shinji Isogami
Emergent ferromagnetism on the surface of recent two-dimensional (2D) MXene is investigated by X-ray magnetic circular dichroism (XMCD) and angle-dependent hard X-ray photoemission spectroscopy (HAXPES). Focusing on the Cr2N as one of the 2D-MXenes, the bilayers of Cr2N/Co and Cr2N/Pt are prepared by magnetron sputtering technique. XMCD reveals the induced magnetic moment of Cr in the Cr2N/Co interface, while it is not observed in the Cr2N/Pt interface at room temperature. To distinguish the possible origins of either the interlayer magnetic exchange coupling or the charge transfer at the interfaces, the additional controlled Cr2N/Cu bilayer, whose work function of Cu is consistent with Co, is prepared. HAXPES spectra for the Cr 2p core level near the interface of Cr2N/Cu is consistent with that of Cr2N/Co, indicating that the induced magnetic moment of Cr observed by XMCD for the Cr2N/Co can be attributed to the interlayer magnetic exchange coupling, rather than the charge transfer, which is a specific characteristics emerged at the interface with 2D-MXene.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
20 PAGES, 4 FIGURES, UNDER REVIEW
Bulk Hydrodynamic Transport in Weyl Semimetals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Joan Bernabeu, Kitinan Pongsangangan, H.T.C. Stoof, Lars Fritz
The role of collective longitudinal modes, plasmons, in bulk hydrodynamic transport in Weyl semimetals is explored. In contrast to graphene, where these modes are gapless, plasmons in Weyl semimetals are gapped. This gap, however, can be made arbitrarily small by decreasing the temperature or the chemical potential, making plasmon modes thermally accessible, both in thermodynamics and transport. In very clean Weyl semimetals near charge-neutrality where the plasmon gap is minimal, we find that they leave an imprint in the thermal conductivity and the viscosity.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
14 pages, 3 figures
Phonon-polaritons in Zn(1-x)MgxTe (x<0.09): A Raman scattering study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
D. Singh, A. Elmahjoubi, O. Pages, V.J.B. Torres, C. Gardiennet, G. Kervern, A. Polian, Y. Le Godec, J.-P. Itie, S. Diliberto, S. Michel, P. Franchetti, K. Strzalkowski
Phonon-polaritons (PP) are phonon-photon coupled modes. Using near-forward Raman scattering, the PP of the cubic Zn(1-x)MgxTe (x<0.09) semiconductor alloy could be measured. While the PP-coupling hardly develops in pure ZnTe, minor Mg-alloying suffices to stabilize a long-lifetime PP strongly bound to the lattice, i.e., with a pronounced phonon character, and yet a fast one originating from the highly dispersive photon-like bottleneck of the PP-dispersion. By combining the advantages of a phonon and of a photon, the long-lifetime PP generated by minor Mg-alloying of ZnTe marks an improvement over the PP of pristine ZnTe, that, from the Raman cross section calculation, can only achieve a balanced compromise between the two kinds of advantages, intensity and speed. The discussion of the PP-related lattice dynamics of Zn(1-x)MgxTe (x<0.09) is grounded in a preliminary study of the lattice macro- and microstructure using X-ray diffraction and solid-state nuclear magnetic resonance, respectively, and further relies on ab initio calculations of the native phonon modes behind the PP in the Mg-dilute limit of Zn(1-x)MgxTe (x~0), considering various Mg-isotopes.
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other)
19 pages, 7 figures
Planar Hall effect in ultrathin topological insulator films
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Mohammad Shafiei, Milorad V. Milošević
The planar Hall effect (PHE), previously observed in Weyl and Dirac semimetals due to the chiral anomaly, emerges with a different origin in topological insulators (TIs), where in-plane magnetic fields induce resistivity anisotropy. In strictly two-dimensional TIs, PHE is generally suppressed due to the inability of the out-of-plane Berry curvature to couple to the in-plane band velocity of the charge carriers. Here, we demonstrate that in ultrathin TI films, a quasi-two-dimensional system, intersurface tunneling coupling with in-plane magnetization induces electronic anisotropy, enabling a finite PHE. In addition, we reveal that strong in-plane magnetization can stabilize the thickness-dependent quantum anomalous Hall effect, typically associated with out-of-plane magnetization. These insights advance the understanding of magnetic topological phases, paving the way for next-generation spintronic devices and magnetic sensing technologies.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Near-room-temperature zero-dimensional polariton lasers with sub-10 GHz linewidths
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Ismael dePedro-Embid, Alexander S. Kuznetsov, Klaus Biermann, Andrés Cantarero, Paulo V. Santos
Narrow and brilliant spectral lines are essential assets for high-resolution spectroscopy as well as for precision sensing and optomechanics. In semiconductor structures and, in particular, in the well-established (Al,Ga)As material system, strong emission lines with nanosecond coherence times can be provided by the opto-electronic resonances of microcavity exciton-polariton condensates. The temporal coherence of these resonances, however, normally rapidly deteriorates as the temperature increases beyond a few tens of kelvins due to exciton dissociation. Here, we demonstrate that the temperature stability of polariton condensates in (Al,Ga)As can be significantly improved by confinement within micrometer-sized intracavity traps. We show that trapped condensates can survive up to ~200 K while maintaining a light-matter character with decoherence rates below 10 GHz (i.e., $ < 40 {\mu}$ eV linewidths). These linewidths are by an order of magnitude smaller than those so far reported for other solid-state systems at these temperatures. Confinement thus provides a pathway towards room-temperature polariton condensation using the well-established (Al,Ga)As material system with prospects for application in scalable on-chip photonic devices for optical processing, sensing, and computing.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Optics (physics.optics)
18 pages, 11 figures
Chiral Domain Walls Induced by Radially Magnetized Nanotube Geometry
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Nobuyuki Umetsu, Hiroki Tokuhira, Michael Quinsat, Hideto Horii, Tsuyoshi Kondo, Masaki Kado
We theoretically investigate chiral domain walls (DWs) formed in radially magnetized nanotubes with perpendicular magnetic anisotropy (PMA). Unlike tubes with an easy axis of magnetization oriented in other directions, radially magnetized tubes exhibit geometrical effects arising not only from exchange interactions but also from magnetostatic interactions, which lead to Dzyaloshinskii-Moriya interaction (DMI)-like effects. We derive expressions for the effective magnetic fields acting on DWs within PMA nanotubes and quantify SOT-driven DW motion using an analytical one-dimensional model, which is validated by micromagnetic simulations. Our results show that the DMI-like field due to magnetostatic interactions can be as significantly as the contribution of the material-induced DMI in nanotubes with diameters below 100$ ,$ nm. This implies that the direction and speed of DW motion in PMA nanotubes could differ from those observed in nanoribbons composed of the same material. Furthermore, we demonstrate that DW velocity can be effectively controlled by adjusting the tube diameter and exchange stiffness constant of the magnetic layer, rather than relying solely on the material-induced DMI. These insights are expected to greatly expand the potential applications of PMA nanotube-based DW devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Effective Theory of Ultrafast Skyrmion Nucleation
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Rein Liefferink, Lukas Körber, Kathinka Gerlinger, Bastian Pfau, Felix Büttner, Johan H. Mentink
Laser-induced ultrafast skyrmion nucleation has been experimentally demonstrated in several materials. So far, atomistic models have been used to corroborate experimental results. However, such simulations do not provide a simple intuitive understanding of the underlying physics. Here, we propose a coarse-grained effective theory where skyrmions can be nucleated or annihilated by thermal activation over energy barriers. Evaluating these two processes during a heat pulse shows good agreement with atomistic spin dynamics simulations and experiments while drastically reducing computational complexity. Furthermore, the effective theory provides a direct guide for experimentally optimizing the number of nucleated skyrmions. Interestingly, the model also predicts a novel pathway for ultrafast annihilation of skyrmions. Our results pave the way for a deeper understanding of ultrafast nanomagnetism and the role of non-equilibrium physics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 4 figures, to be submitted to Physical Review Letters
Floquet realization of prethermal Meissner phase in a two-leg flux ladder
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-04-16 20:00 EDT
Biswajit Paul, Tapan Mishra, K. Sengupta
We show that a periodically driven two-leg flux ladder hosting interacting hardcore bosons exhibits a prethermal Meissner phase for large drive amplitudes and at special drive frequencies. Such a prethermal Meissner phase is characterized by a finite time-averaged chiral current. We find an analytic expression of these frequencies using Floquet perturbation theory. Our analysis reveals that the presence of the prethermal Meissner phase is tied to the emergence of strong Hilbert space fragmentation in these driven ladders. We support our analytical results by numerical study of finite-size flux ladders using exact diagonalization and discuss experiments using ultracold dipolar atom platforms that may test our theory.
Quantum Gases (cond-mat.quant-gas), Other Condensed Matter (cond-mat.other)
4+5 pages, 4+5 figs
Tunable self-emulsification via viscoelastic control of Marangoni-driven interfacial instabilities
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-04-16 20:00 EDT
Christoph Haessig, Mehdi Habibi, Uddalok Sen
Interfacial instabilities in multicomponent fluidic systems are widespread in nature and in industrial processes, yet controlling their dynamics remains a challenge. Here, we present a strategy to actively tune Marangoni-driven self-emulsification at liquid-liquid interfaces by harnessing fluid viscoelasticity. When a water-alcohol droplet spreads on an oil bath, a radial surface tension gradient induced by selective alcohol evaporation drives an interfacial instability, leading to the spontaneous formation of a dense two-dimensional array of “daughter” droplets. We demonstrate that introducing trace amounts of high-molecular-weight polymers, which introduces viscoelasticity, provides a robust means of controlling this process. Increasing viscoelasticity systematically suppresses the instability, resulting in a delayed onset of fragmentation and longer spreading fingers. By combining high-resolution experimental visualization and theoretical analysis, we uncover a quantitative relationship between the polymer concentration and the finger length prior to breakup. These findings establish a predictive framework for designing viscoelastic interfacial materials with programmable dynamic and offer new opportunities for surface-tension-mediated patterning, emulsification, and fluidic control in soft material systems.
Soft Condensed Matter (cond-mat.soft), Fluid Dynamics (physics.flu-dyn)
From Heteropolymer Stiffness Distributions to Effective Homopolymers: A Conformational Analysis of Intrinsically Disordered Proteins
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-04-16 20:00 EDT
Yannick Witzky, Friederike Schmid, Arash Nikoubashman
Intrinsically disordered proteins (IDPs) are characterized by a lack of defined secondary and tertiary structures, and are thus well-suited for descriptions within polymer theory. However, the intrinsic heterogeneity of proteins, stemming from their diverse amino acid building blocks, introduces local variations in chain stiffness, which can impact conformational behavior at larger scales. To investigate this effect, we developed a heterogeneous worm-like chain model in which the local persistence length follows a Gaussian distribution. We demonstrate that these heterogeneous chains can be effectively mapped to homogeneous chains with a single effective persistence length. To assess whether this mapping can be extended to naturally occurring IDPs, we performed simulations using various coarse-grained IDP models, finding that the simulated IDPs have similar shapes like the corresponding homogeneous and heterogeneous worm-like chains. However, the IDPs are systematically larger than ideal worm-like chains, yet slightly more compact when excluded volume interactions are considered. We attribute these differences to intramolecular interactions between non-bonded monomers, which our theoretical models do not account for.
Soft Condensed Matter (cond-mat.soft)
Modeling dislocations in quasicrystals through amplitude equations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Marcello De Donno, Luiza Angheluta, Marco Salvalaglio
Quasicrystals (QCs) are a class of aperiodic ordered structures that emerge in various systems, from metallic alloys to soft matter and driven non-equilibrium systems. Within a mesoscale theory based on slowly-varying complex amplitudes for QCs, we track dislocations as topological defects harbored by the amplitudes and characterize their Burgers vectors and induced deformations. We study the formation of dislocations at semicoherent interfaces, particularly those emerging from rotated inclusions, and find a hierarchy of dislocations forming at such interfaces. We further analyze interfaces in strained systems, revealing conditions for the emergence of periodic dislocation arrays and discussing the energetics of dislocations associated with different phonon and phason deformations. The stability, interaction, and motion of dislocation dipoles and quadrupoles are also discussed. These findings provide new insights into the mesoscale modeling of dislocations in QCs and their distinct behavior compared to conventional crystals, while demonstrating a versatile framework for studying dislocations in systems exhibiting quasicrystalline order.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Soft Condensed Matter (cond-mat.soft)
15 pages, 5 figures
Single-site and multi-site solitons of bright matter-waves in optical lattices
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-04-16 20:00 EDT
Robbie Cruickshank, Francesco Lorenzi, Arthur La Rooij, Ethan Kerr, Timon Hilker, Stefan Kuhr, Luca Salasnich, Elmar Haller
We report the experimental observation of discrete bright matter-wave solitons with attractive interaction in an optical lattice. Using an accordion lattice with adjustable spacing, we prepare a Bose-Einstein condensate of cesium atoms across a defined number of lattice sites. By quenching the interaction strength and the trapping potential, we generate both single-site and multi-site solitons. Our results reveal the existence and characteristics of these solitons across a range of lattice depths and spacings. We identify stable regions of the solitons, based on interaction strength and lattice properties, and compare these findings with theoretical predictions. Our results provide insights into the quench dynamics and collapse mechanisms, paving the way for further studies on transport and dynamical properties of matter-wave solitons in lattices.
Quantum Gases (cond-mat.quant-gas), Pattern Formation and Solitons (nlin.PS), Quantum Physics (quant-ph)
8 pages, 9 figures
Weyl-mediated Ruderman-Kittel-Kasuya-Yosida interaction revisited: imaginary-time formalism and finite temperature effects
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Mengyao Zhou, Hao-Ran Chang, Lijun Yang, Long Liang
Noncentrosymmetric magnetic Weyl semimetals provide a platform for investigating the interplay among magnetism, inversion symmetry breaking, and topologically nontrivial Weyl fermions. The Weyl-mediated Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction may be related to the magnetic orders observed in rare-earth magnetic Weyl semimetals. Previous studies of RKKY interaction between magnetic impurities in Weyl semimetals found Heisenberg, Ising-like, and Dzyaloshinskii-Moriya (DM) types of interactions. However, different range functions are obtained in the literature. In this work, we calculate the Weyl-mediated RKKY interaction by using the divergence-free imaginary-time formalism and obtain exact analytical results at finite temperature. The discrepancies among zero temperature range functions in the literature are resolved. At nonzero temperature, the interaction strength decays exponentially in the long distance limit. But in the short distance limit, the DM interaction shows a thermal enhancement, an effect persists up to higher temperature for shorter distance. This provides a mechanism stabilizing the helical order observed in rare-earth magnetic Weyl semimetals.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
11 pages and 4 figures
Spin demons in d-wave altermagnets
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Pieter M. Gunnink, Jairo Sinova, Alexander Mook
Demons are a type of plasmons, which consist of out-of-phase oscillations of electrons in different bands. Here, we show that $ d$ -wave altermagnets, a recently discovered class of collinear magnetism, naturally realize a spin demon, which consists of out-of-phase movement of the two spin species. The spin demon lives outside of the particle-hole continuum of one of the spin species, and is therefore significantly underdamped, reaching quality factors of $ >10$ . We show that the spin demon carries a magnetic moment, which inherits the $ d$ -wave symmetry. Finally, we consider both three and two dimensional $ d$ -wave altermagnets, and show that spin demons exists in both.
Strongly Correlated Electrons (cond-mat.str-el)
Supplementary Material (SM) available under “Ancillary files”. Data available at this https URL
Electronic transport properties of titanium nitride grown by molecular beam epitaxy
New Submission | Superconductivity (cond-mat.supr-con) | 2025-04-16 20:00 EDT
Kosuke Takiguchi, Yoshiharu Krockenberger, Tom Ichibha, Kenta Hongo, Ryo Maezono, Yoshitaka Taniyasu, Hideki Yamamoto
This study investigates the molecular beam epitaxial (MBE) growth of titanium nitride (TiN) thin films, achieving a high residual resistivity ratio (RRR) of 15.8. We observed a strong correlation between growth temperature and crystalline quality, as reflected in both RRR values and lattice parameter variations. Characterization of superconductivity yielded a Ginzburg-Landau coherence length of 60.4 $ \pm$ 0.6 nm, significantly higher than typical sputtered films, suggesting improved superconducting coherence. First-principles calculations, in conjunction with experimental data, provided detailed insights into the electronic structure and transport properties of the TiN films. Temperature-dependent Hall coefficient measurements further revealed the influence of anisotropic scattering mechanisms. These findings establish a promising route for the development of nitride-based superconducting materials for advanced quantum computing technologies.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
Uncertainty-aware electronic density-functional distributions
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Teitur Hansen, Jens Jørgen Mortensen, Thomas Bligaard, Karsten Wedel Jacobsen
We introduce a method for the estimation of uncertainties in density-functional-theory (DFT) calculations for atomistic systems. The method is based on the construction of an uncertainty-aware functional distribution (UAFD) in a space spanned by a few different exchange-correlation functionals and is illustrated at the level of generalized-gradient-approximation functionals. The UAFD provides reliable estimates of errors – compared to experiments or higher-quality calculations – in calculations performed self-consistently with the Perdew-Burke-Ernzerhof functional. The scheme furthermore allows for a decomposition of the error into a systematic bias and a reduced error. The approach is applied to four different properties: molecular atomization energies, cohesive energies, lattice constants, and bulk moduli of solids. The probability distribution can be tailored to optimize the prediction of a single property or for several properties simultaneously.
Materials Science (cond-mat.mtrl-sci), Data Analysis, Statistics and Probability (physics.data-an)
8 pages, 4 figures
Magnetotransport and activation energy of the surface states in Cd3As2 thin films
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Zhigang Cai, Fuxiang Li, Yi-Xiang Wang
Recent experiments performed the magnetotransport measurements in (001)-oriented Cd$ _3$ As$ _2$ thin films and attributed the magnetotransport properties to the surface states. In this paper, by using an effective model to describe the surface states, we analyze the Landau bands and then calculate the magnetoconductivities and magnetoresistivities. From these results, the features of two-dimensional quantum Hall effect of the surface states can be captured. More importantly, we reveal that the activation energy is determined by the Hall plateau width, which can explain the experimental observations that the activation energies at odd plateaus are larger than those at even plateaus. We also analyze the roles played by the structural inversion symmetry breaking and impurity scatterings in the magnetotransport, and suggest that their combined effects would lead to the absence of some Hall plateaus.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 6 figures
Physics Letters A 534, 130231 (2025)
Electron-transverse acoustic phonon couplings in three-dimensional pentatellurides
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Rui Min, Fuxiang Li, Yi-Xiang Wang
Transverse acoustic (TA) phonon waves are analogous to electromagnetic waves and can carry a certain angular momentum. In this paper, we study the electron-TA phonon couplings in three-dimensional pentatellurides and explore the conditions under which the TA phonon condensation is stable. We analyze the Lindhard response function, phonon softening, mean-field parameters, and renormalized dispersions, on the basis of which the phase diagrams of the electron-phonon couplings in ZrTe$ _5$ and HfTe$ _5$ are calculated. The phase diagrams show that, if the chemical potential lies near the Weyl nodes, the TA phonon condensation will dominate and lead to the shear strain wave phase. We further reveal that when the wave vector of the particular phonon mode is smaller, the critical coupling strength will be weaker for the phonon condensation, which thus favors the condensation phase.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 5 figures
Physical Review B 111, 165204 (2025)
Compositional Effects on Structure, Dynamics, Thermodynamic and Mechanical Properties of Zr-Cu-Al alloys
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Kamal G. Soni, Jayraj P. Anadani, Mitanshu B. Vahiya, Kirit N. Lad
Zr-Cu-Al alloys belong to a commercially important family of CuZr-based alloys that form bulk metallic glasses on microalloying of Al. However, the identification of compositions with good glass-forming ability and desirable properties from a vast compositional space remains a major challenge due to complex compositional effects on the structure, dynamics and properties. In the present work, we report molecular dynamic investigations of structure, dynamics, thermodynamic and mechanical properties of Zr$ _{50}$ Cu$ _{50-x}$ Al$ _x$ and Cu$ _{50}$ Zr$ _{50-x}$ Al$ _x$ alloys ($ x=5,10,15,20,25,30,40$ ) covering a wide compositional space. Our results and findings lead to some important conclusions that could serve as overarching guidelines for choosing good glass-forming alloy compositions that give Zr-Cu-Al glasses with tailored thermal and mechanical properties. Overall, present results suggest that a good glass-forming Zr-Cu-Al alloy composition leading to an MG with good thermal and mechanical properties should be Cu-rich with Zr concentration in the window 30%-35% and Al% > 20. Our results also highlight the impact of icosahedral short- and medium-range ordering on the dynamics and mechanical properties of the alloys. It is observed that the fractions of the full icosahedra $ \langle 0,0,12,0 \rangle$ and the degree of their interconnectivity are directly correlated to the structural relaxation, diffusion, dynamic heterogeneity and mechanical properties.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn)
28 pages, 13 Figures (Main Manuscript), 3 pages, 3 Figures (Supplementary Material)
Asymmetric Resonant Ferroelectric Tunnel Junctions for Simultaneous High Tunnel Electroresistance and Low Resistance-Area Product
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Balram Khattar, Adarsh Tripathi, Manmohan Brahma, Abhishek Sharma
Ferroelectric tunnel junctions offer potential for non-volatile memory with low power, fast switching, and scalability, but their performance is limited by a high resistance-area product and a low tunnel electroresistance ratio. To address these challenges, we propose a doped HfO2-based, silicon-compatible asymmetric resonant ferroelectric tunnel junction design with a quantum well embedded between two ferroelectric layers, replacing the conventional metal-ferroelectric-metal structure. Using a self-consistent coupling of the non-equilibrium Green’s function method with a Preisach-based model, we demonstrate that the quantum well enhances resonant tunneling effects, leading to a simultaneous reduction in the resistance-area product and a boost in the tunnel electroresistance ratio. The low-resistance state becomes more robust, while the high-resistance state is suppressed, improving readout speed and reducing power usage. We observed that incorporating a 2 nm quantum well significantly enhances the tunnel electroresistance ratio, achieving a peak value of approximately 6.15 x 10^4 percent, while simultaneously minimizing the resistance-area product to 47.1 Ohm-cm^2 at 0.175 V. Additionally, the device exhibits negative differential resistance, further enhancing its functionality. Our results confirm that this design enables scalable, energy-efficient, and high-performance non-volatile memory, making it a strong candidate for future memory technologies.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Nonreciprocal Spin-Wave Propagation in Anisotropy-Graded Iron Films Prepared by Nitrogen Implantation
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
L. Christienne, J. Jiménez-Bustamante, P. Rovillain, Mahmoud Eddrief, Yunlin Zheng, Franck Fortuna, Massimiliano Marangolo, M. Madami, R. A. Gallardo, P. Landeros, S. Tacchi
Gradual modification of the magnetic properties in ferromagnetic films has recently been proposed as an effective method to channel and control spin waves for the development of new functionalities in magnonic devices. Here, we investigate graded FeN films prepared by low-dose nitrogen implantation of Fe epitaxial thin films. Combining Brillouin light scattering measurements and a spin-wave theoretical approach, we show that nitrogen implantation induces a graded profile of both the in-plane and the perpendicular anisotropies along the film thickness. This graduation leads to a significant modification of the spin-wave spatial localization and generates a marked frequency asymmetry in the spin-wave dispersion. Moreover, we find that the anisotropy profile, and as a consequence the dispersion relation, can be tuned on changing the implantation dose, opening a way for the potential use of the graded Fe-N films in magnonic applications.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Soft Condensed Matter (cond-mat.soft)
The interplay between Jahn-Teller distortions and structural degrees of freedom on pseudocubic states in manganite perovskites
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Ben R. M. Tragheim, Elodie A. Harbourne, Clemens Ritter, Andrew L. Goodwin, Mark S. Senn
The average structure of the solid solution LaMn$ _{1-x}$ Ga$ _x$ O$ _3$ (LMGO) has been investigated from a symmetry-motivated approach utilizing synchrotron x-ray and neutron powder diffraction techniques. We show experimentally that a trilinear coupling term ($ \Gamma_5^+$ M$ _2^+$ M$ _3^+$ ) between shear strain, octahedral rotation, and the $ C$ -type orbital ordering mode is responsible for driving the orthorhombic to pseudocubic phase transition occurring in the composition range 0.5 $ <$ $ x$ $ <$ 0.6. Our Monte Carlo simulations elucidate the macroscopic origin of this coupling to shear strain, and point to its importance with respect to controlling the orbital order-disorder transitions. We find that the emergence of the pseudocubic state can be rationalized by considering the competition between this trilinear term and a linear-quadratic term of the out-of-phase octahedral tilting with strain ($ \Gamma_5^+$ (R$ _5^-$ )$ ^2$ ). Illustrating the general nature of these results, we construct a simple function that captures the change in Landau free energy at the order-disorder transition, in parameters that are trivial to relate to the concentration of Jahn–Teller active species, temperature, tolerance factor and unit cell strain, for a broad range of manganite perovskites. Our results point to the fact that far from the pseudocubic state being a symptom of orbital disorder, it is in many cases more correctly to view it as a cause. The results have a broad impact on the study of orbital ordering physics in the perovskite materials and on chemical and physical control parameters through which to tune the richness of the intertwined physical properties.
Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 4 figures
Adjustable Molecular Cross-Linkage of MXene Layers for Tunable Charge Transport and VOC Sensing
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Yudhajit Bhattacharjee, Lukas Mielke, Mahmoud Al-Hussein, Shivam Singh, Karen Schaefer, Anik Kumar Ghosh, Carmen Herrmann, Yana Vaynzof, Andreas Fery, Hendrik Schlicke
MXenes, two-dimensional transition metal carbides, nitrides or carbonitrides, are emerging as highly promising materials due to their remarkable charge transport characteristics and their versatile surface chemistry. Herein, we demonstrate the tunability of interfaces and the inter-layer spacing between Ti$ _3$ C$ _2$ T$ _X$ MXene flakes through molecular cross-linking via ligand exchange with homologous diamines. Oleylamine was initially introduced as a ligand, to facilitate the delamination and stable dispersion of pristine Ti$ _3$ C$ _2$ T$ _X$ flakes in chloroform. Subsequently, controlled cross-linkage of the flakes was achieved using diamine ligands with varying aliphatic chain lengths, enabling the precise tuning of the inter-layer spacing. Grazing incidence X-ray scattering (GIXRD / GIWAXS) confirmed the correlation between ligand chain length and inter-layer spacing, which was further supported by Density Functional Theory (DFT) calculations. Furthermore, we investigated the charge transport properties of thin films consisting of these diamine cross-linked MXenes and observed a strong dependence of the conductivity on the interlayer spacing. Finally, we probed chemiresistive vapor sensing properties of the MXene composites and observed a pronounced sensitivity and selectivity towards water vapor, highlighting their potential for use in humidity sensors. Providing significant insights into molecular cross-linking of MXenes to form hybrid inorganic/organic composites and its consequences for charge transport, this study opens avenues for the development of next-generation MXene-based electronic devices.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Algorithmic thresholds in combinatorial optimization depend on the time scaling
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-04-16 20:00 EDT
M. C. Angelini, M. Avila-González, F. D’Amico, D. Machado, R. Mulet, F. Ricci-Tersenghi
In the last decades, many efforts have focused on analyzing typical-case hardness in optimization and inference problems. Some recent work has pointed out that polynomial algorithms exist, running with a time that grows more than linearly with the system size, which can do better than linear algorithms, finding solutions to random problems in a wider range of parameters. However, a theory for polynomial and superlinear algorithms is in general lacking. In this paper, we examine the performance of the Simulated Annealing algorithm, a standard, versatile, and robust choice for solving optimization and inference problems, in the prototypical random $ K$ -Sat problem. For the first time, we show that the algorithmic thresholds depend on the time scaling of the algorithm with the size of the system. Indeed, one can identify not just one, but different thresholds for linear, quadratic, cubic regimes (and so on). This observation opens new directions in studying the typical case hardness in optimization problems.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
Pressure-Tunable Generalized Wigner Crystal and Fractional Chern Insulator in twisted MoTe$_2$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Bingbing Wang, Junxi Yu, Prakash Sharma, Cheng-Cheng Liu
Due to the forming of low-energy flat bands, the moiré superlattices of the transition metal dichalcogenides are fascinating platforms for studying novel correlated states when such flat bands are fractionally filled, with the Coulomb interaction dominating. Here, we demonstrate that pressure can efficiently tune the flatness and quantum geometry of the single-particle bands in twisted bilayer MoTe$ _2$ ($ \textit{t}$ MoTe$ _2$ ). By fractionally filling the topmost valence band, we find that pressure can act as a flexible means to modulate the fractional Chern insulator (FCI) and the generalized Wigner crystal (GWC) and control their many-body topological phase transitions. Moreover, our results indicate a remarkable correspondence between the single-particle band geometry and the formation of FCI and GWC. As the recent experiments report the presence of FCI phases in $ \textit{t}$ MoTe$ _2$ , our predictions could be readily implemented experimentally.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Discontinuous depinning/yielding transition of elastic manifolds with tailored internal elasticity
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-04-16 20:00 EDT
We consider elastic manifolds evolving on disordered energy potentials under the action of an external uniform driving. This scenario includes the cases of {\em depinning} and {\em yielding}, which provide paradigmatic examples of out of equilibrium phase transitions. In both cases, velocity of the manifold is zero at low driving force, and increases smoothly when a critical driving is exceeded,defining a continuous flow-curve for these systems. We show that when more general forms of the manifold elasticity are considered, the flow curve may become reentrant, and the transition hysteretic, or discontinuous. This constitutes a novel scenario for a discontinuous transition out of equilibrium.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
6pages, 6 figures
Accurate Machine Learning Interatomic Potentials for Polyacene Molecular Crystals: Application to Single Molecule Host-Guest Systems
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Burak Gurlek, Shubham Sharma, Paolo Lazzaroni, Angel Rubio, Mariana Rossi
Emerging machine learning interatomic potentials (MLIPs) offer a promising solution for large-scale accurate material simulations, but stringent tests related to the description of vibrational dynamics in molecular crystals remain scarce. Here, we develop a general MLIP by leveraging the graph neural network-based MACE architecture and active-learning strategies to accurately capture vibrational dynamics across a range of polyacene-based molecular crystals, namely naphthalene, anthracene, tetracene and pentacene. Through careful error propagation, we show that these potentials are accurate and enable the study of anharmonic vibrational features, vibrational lifetimes, and vibrational coupling. In particular, we investigate large-scale host-guest systems based on these molecular crystals, showing the capacity of molecular-dynamics-based techniques to explain and quantify vibrational coupling between host and guest nuclear motion. Our results establish a framework for understanding vibrational signatures in large-scale complex molecular systems and thus represent an important step for engineering vibrational interactions in molecular environments.
Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
Ab initio Maxwell-Bloch Approach for X-Ray Excitations in Two-Dimensional Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Joris Sturm, Ivan Maliyov, Dominik Christiansen, Malte Selig, Marco Bernardi, Andreas Knorr
The combination of Maxwell and X-ray Bloch equations forms an appropriate framework to describe ultrafast time-resolved X-ray experiments on attosecond time scale in crystalline solids. However, broadband experiments such as X-ray absorption near edge spectroscopy or resonant inelastic X-ray scattering require a detailed knowledge of the electronic structure and transition matrix elements. Here, we show how to fill this gap by combining the Maxwell-X-ray Bloch formalism with first-principles calculations treating explicitly the core states. The resulting X-ray absorption spectrum recovers key spectral signatures which were missing in our previous work relying on a semi-empirical tight-binding approach.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Emergent Magnetic Structures at the 2D Limit of the Altermagnet MnTe
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Marc G. Cuxart, Roberto Robles, Beatriz Muñiz Cano, Pierluigi Gargiani, Clara Rebanal, Iolanda Di Bernardo, Alireza Amiri, Fabián Calleja, Manuela Garnica, Miguel A. Valbuena, Amadeo L. Vázquez de Parga
MnTe has recently emerged as a canonical altermagnet, a newly identified class of magnetism characterized by compensated antiferromagnetic order coexisting with spin-split electronic bands, traditionally considered exclusive to ferromagnets. However, the extent to which altermagnetism persists as altermagnets are thinned to the two-dimensional (2D) limit remains unexplored. Here, we investigate the magnetic behaviour of 2D MnTe, specifically atomically-thin monolayers (MLs) and bilayers (BLs) grown on graphene/Ir(111) substrate, by combining experimental scanning tunneling microscopy, x-ray photoelectron spectroscopy, x-ray absorption spectroscopy and x-ray magnetic circular dichroism with density functional theory calculations. We find that while ML and BL MnTe adopt atomic structures with symmetries incompatible with altermagnetism, they exhibit intriguing magnetic phases: the BL forms a highly-robust layered antiferromagnet with in-plane spin anisotropy, whereas the ML exhibits a spin-glass-like behavior below its freezing temperature, a phenomenon not previously observed in an atomically thin material. These findings highlight how reduced dimensionality can promote the emergence of unusual magnetic structures distinct from those of their three-dimensional counterparts, providing new insights into low-dimensional magnetism.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Influence of a Xenon interlayer on dissociative electron attachment to deuterated methane on a platinum substrate
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Norhan Omar, Pierre Cloutier, Christophe Ramseyer, Léon Sanche, Michel Fromm
We investigate the impact of intercalating a xenon layer between a thin condensed CD4 film of two monolayers (ML) and a platinum surface on the dissociative electron attachment (DEA). The observed desorption results are compared with density functional theory (DFT) calculations, which reveal the binding energies of various anionic and neutral species as a function of the xenon film thickness on the Pt (111) substrate. The theoretical results suggest that 6 ML of xenon are sufficient to diminish the surface effect, enabling physisorbed anionic fragments to desorb from the CD4 film. In contrast, 20 ML (approximately 10 nm) are experimentally necessary to achieve saturation in the desorption of D-. In addition, the presence of xenon layers enables the coupling of resonance states with Xe excited states, thereby inhibiting the electrons from returning to the metal. Aside from reducing surface interactions, the xenon interlayer significantly enhances DEA to CD4.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph), Computational Physics (physics.comp-ph)
Remote electric-field control of antiferromagnetic magnon-polaritons
New Submission | Other Condensed Matter (cond-mat.other) | 2025-04-16 20:00 EDT
Dmitriy Yavorskiy, Jan Suffczyński, Rafał Kowerdziej, Olga Strzeżysz, Jerzy Wróbel, Wojciech Knap, Marcin Białek
The control of hybrid light-matter states, specifically magnon-polaritons that emerge from the strong coupling between magnons and cavity photons, remains a key challenge in developing reconfigurable quantum and classical devices. Here, we showcase the ability to remotely control antiferromagnetic magnon-polaritons at room temperature using electric field by integrating a highly birefringent liquid crystal layer into a terahertz Fabry-Pérot cavity containing an antiferromagnetic crystal. Positioned several millimeters from the magnetic material, the liquid crystal allows for adjusting the cavity’s photonic environment through electric field. This adjustment, in turn, influences the coupling strength of a particular cavity mode to the magnon resonance, thereby controlling the extent of magnon dressing by cavity photons. Our approach facilitates dynamic and reversible tuning of magnon-photon hybridization without the need for direct electrical contact or alterations to the magnetic medium. These findings create the conditions for voltage-programmable terahertz magnonic devices and new possibilities for noninvasive control strategies in spin-based information processing technologies.
Other Condensed Matter (cond-mat.other)
Current response to axial gauge fields in noncentrosymmetric magnetic Weyl semimetals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
We investigate the electric current response to axial gauge fields in noncentrosymmetric magnetic Weyl semimetals. The absence of both time-reversal and inversion symmetries allows for new types of responses. We systematically calculate the transverse, longitudinal, and Hall responses to axial gauge potentials with both linear and quadratic dispersion relations. The transverse and Hall responses are of comparable magnitude, while the longitudinal response is much smaller. Notably, with increasing frequency, the transverse and Hall response functions manifest a peak whose height is determined by the properties of Weyl fermions and is independent of the axial gauge potential. The main features of the response functions survive in the presence of disorders. As applications of our results, we propose a Hall type magnetopiezoelectric effect, where a transverse sound wave can induce an electric current whose direction is perpendicular to the directions of sound propagation and polarization. Our results also provide a mechanism to excite magnons using electric fields and could be useful for magnon spintronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
7 pages and 4 figures
Giant Magnetocaloric Effect in Spin Supersolid Candidate Na$_2$BaCo(PO$_4$)$_2$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Junsen Xiang, Chuandi Zhang, Yuan Gao, Wolfang Schmidt, Karin Schmalzl, Chin-Wei Wang, Bo Li, Ning Xi, Xin-Yang Liu, Hai Jin, Gang Li, Jun Shen, Ziyu Chen, Yang Qi, Yuan Wan, Wentao Jin, Wei Li, Peijie Sun, Gang Su
Supersolid, an exotic quantum state of matter that consists of particles forming an incompressible solid structure while simultaneously showing superfluidity of zero viscosity [1], is one of the long-standing pursuits in fundamental research [2, 3]. Although the initial report of $ ^4$ He supersolid turned out to be an artifact [4], this intriguing quantum matter has inspired enthusiastic investigations into ultracold quantum gases [5-8]. Nevertheless, the realization of supersolidity in condensed matter remains elusive. Here we find evidence for a quantum magnetic analogue of supersolid – the spin supersolid – in the recently synthesized triangular-lattice antiferromagnet Na$ _2$ BaCo(PO$ _4$ )$ _2$ [9]. Notably, a giant magnetocaloric effect related to the spin supersolidity is observed in the demagnetization cooling process, manifesting itself as two prominent valley-like regimes, with the lowest temperature attaining below 100 mK. Not only is there an experimentally determined series of critical fields but the demagnetization cooling profile also shows excellent agreement with the theoretical simulations with an easy-axis Heisenberg model. Neutron diffractions also successfully locate the proposed spin supersolid phases by revealing the coexistence of three-sublattice spin solid order and interlayer incommensurability indicative of the spin superfluidity. Thus, our results indicate a strong entropic effect of the spin supersolid phase in a frustrated quantum magnet and open up a viable and promising avenue for applications in sub-Kelvin refrigeration, especially in the context of persistent concerns about helium shortages [10, 11].
Strongly Correlated Electrons (cond-mat.str-el)
19 pages, 13 figures
Nature volume 625, pages 270-275 (2024)
Energy-resolved tip-orbital fingerprint in scanning tunneling spectroscopy based on the revised Chen’s derivative rule
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Ivan Abilio, Krisztián Palotás
The revised Chen’s derivative rule for electron tunneling is implemented to enable computationally efficient first-principles-based calculations of the differential conductance dI/dV for scanning tunneling spectroscopy (STS) simulations. The probing tip is included through a single tip apex atom, and its electronic structure can be modeled as a linear combination of electron orbitals of various symmetries, or can be directly transferred from first-principles electronic structure calculations. By taking pristine and boron- or nitrogen-doped graphene sheets as sample surfaces, the reliability of our implementation is demonstrated by comparing its results to those obtained by the Tersoff-Hamann and Bardeen’s electron tunneling models. It is highlighted that the energy-resolved direct and interference contributions to dI/dV arising from the tip’s electron orbitals result in a fingerprint of the particular combined surface-tip system. The significant difference between the electron acceptor boron and donor nitrogen dopants in graphene is reflected in their dI/dV fingerprints. The presented theoretical method allows for an unprecedented physical understanding of the electron tunneling process in terms of tip-orbital-resolved energy-dependent dI/dV maps, that is anticipated to be extremely useful for investigating the local electronic properties of novel material surfaces in the future.
Materials Science (cond-mat.mtrl-sci)
12 pages, 5 figures, 4 tables
Crystal nucleation and growth in high-entropy alloys revealed by atomic electron tomography
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Yakun Yuan, Saman Moniri, Yao Yang, Jihan Zhou, Andrew Yuan, Dennis S. Kim, Yongsoo Yang, Chenyang Li, Wei Chen, Peter Ercius, Jianwei Miao
High-entropy alloys (HEAs) balance mixing entropy and intermetallic phase formation enthalpy, creating a vast compositional space for structural and functional materials (1-6). They exhibit exceptional strength-ductility trade-offs in metallurgy (4-10) and near-continuum adsorbate binding energies in catalysis (11-16). A deep understanding of crystal nucleation and growth in HEAs is essential for controlling their formation and optimizing their structural and functional properties. However, atomic-scale nucleation in HEAs challenges traditional theories based on one or two principal elements (17-23). The intricate interplay of structural and chemical orders among multiple principal elements further obscures our understanding of nucleation pathways (5,24-27). Due to the lack of direct three-dimensional (3D) atomic-scale observations, previous studies have relied on simulations and indirect measurements (28-32), leaving HEA nucleation and growth fundamentally elusive. Here, we advance atomic electron tomography (33,34) to resolve the 3D atomic structure and chemical composition of 7,662 HEA and 498 medium-entropy alloy nuclei at different nucleation stages. We observe local structural order that decreases from core to boundary, correlating with local chemical order. As nuclei grow, structural order improves. At later stages, most nuclei coalesce without misorientation, while some form coherent twin boundaries. To explain these experimental observations, we propose the gradient nucleation pathways model, in which the nucleation energy barrier progressively increases through multiple evolving intermediate states. We expect these findings to not only provide fundamental insights into crystal nucleation and growth in HEAs, but also offer a general framework for understanding nucleation mechanisms in other materials.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn), Soft Condensed Matter (cond-mat.soft)
Hunting for Maxwell’s Demon in the Wild
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-04-16 20:00 EDT
Johan du Buisson, Jannik Ehrich, Matthew P. Leighton, Avijit Kundu, Tushar K. Saha, John Bechhoefer, David A. Sivak
The apparent paradox of Maxwell’s demon motivated the development of information thermodynamics and, more recently, engineering advances enabling the creation of nanoscale information engines. From these advances, it is now understood that nanoscale machines like the molecular motors within cells can in principle operate as Maxwell demons. This motivates the question: does information help power molecular motors? Answering this would seemingly require simultaneous measurement of all system degrees of freedom, which is generally intractable in single-molecule experiments. To overcome this limitation, we derive a statistical estimator to infer both the direction and magnitude of subsystem heat flows, and thus to determine whether – and how strongly – a motor operates as a Maxwell demon. The estimator uses only trajectory measurements for a single degree of freedom. We demonstrate the estimator by applying it to simulations of an experimental realization of an information engine and a kinesin molecular motor. Our results show that kinesin transitions to a Maxwell-demon mechanism in the presence of nonequilibrium noise, with a corresponding increase in velocity consistent with experiments. These findings suggest that molecular motors may have evolved to leverage active fluctuations within cells.
Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph)
12 pages, 5 figures
Organisation and dynamics of individual DNA segments in topologically complex genomes
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-04-16 20:00 EDT
Saminathan Ramakrishnan, Auro Varat Patnaik, Guglielmo Grillo, Luca Tubiana, Davide Michieletto
Capturing the physical organisation and dynamics of genomic regions is one of the major open challenges in biology. The kinetoplast DNA (kDNA) is a topologically complex genome, made by thousands of DNA (mini and maxi) circles interlinked into a two-dimensional Olympic network. The organisation and dynamics of these DNA circles are poorly understood. In this paper, we show that dCas9 linked to Quantum Dots can efficiently label different classes of DNA minicircles in kDNA. We use this method to study the distribution and dynamics of different classes of DNA minicircles within the network. We discover that maxicircles display a preference to localise at the periphery of the network and that they undergo subdiffusive dynamics. From the latter, we can also quantify the effective network stiffness, confirming previous indirect estimations via AFM. Our method could be used more generally, to quantify the location, dynamics and material properties of genomic regions in other complex genomes, such as that of bacteria, and to study their behaviour in the presence of DNA-binding proteins.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
Deciphering the Structure of Push-Pull Conjugated Polymer Aggregates in Solution and Film
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-04-16 20:00 EDT
Thomas P. Chaney, Christine LaPorte Mahajan, Masoud Ghasemi, Andrew J. Levin, Keith P. White, Scott T. Milner, Enrique D. Gomez, Michael F. Toney
The morphology of conjugated polymer films is highly tunable, influencing their performance in organic electronics. Specifically, molecular packing or crystal structure strongly influence electronic processes such as light absorption and charge transfer. However, the unit cells of high-performance electron donor polymers remain unknown, limiting the understanding of how processing affects structure and device performance. This study characterizes the aggregate structure of PM6-type push-pull polymers using X-ray scattering, cryogenic electron microscopy, and molecular dynamics (MD) simulations. A novel forward simulation approach linking grazing-incidence wide-angle X-ray scattering (GIWAXS) with MD resolves a monoclinic unit cell that accurately describes PM6-type polymer aggregates in both thin films and casting solutions. Intimate pi-pi stacking between donor and acceptor units emerges from this unit cell. Analysis of experimental GIWAXS using this unit cell quantifies sliding disorder in these aggregates, which may impact device performance. The shape and internal structure of solution aggregates are also identified in chlorobenzene. These findings enhance our understanding of PM6-type polymer packing, outline a strategy for elucidating the crystal structure of weakly ordered materials, and provide an opportunity to control optoelectronic performance through aggregate formation in PM6 and other push-pull conjugated polymers.
Materials Science (cond-mat.mtrl-sci), Soft Condensed Matter (cond-mat.soft)
Main text: 29 pages, 6 figures. Supporting Information: 16 pages, 19 figures
Taxonomy of Prediction
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-04-16 20:00 EDT
Alexandra Jurgens, James P. Crutchfield
A prediction makes a claim about a system’s future given knowledge of its past. A retrodiction makes a claim about its past given knowledge of its future. We introduce the ambidextrous hidden Markov chain that does both optimally – the bidirectional machine whose state structure makes explicit all statistical correlations in a stochastic process. We introduce an informational taxonomy to profile these correlations via a suite of multivariate information measures. While prior results laid out the different kinds of information contained in isolated measurements, in addition to being limited to single measurements the associated informations were challenging to calculate explicitly. Overcoming these via bidirectional machine states, we expand that analysis to information embedded across sequential measurements. The result highlights fourteen new interpretable and calculable information measures that fully characterize a process’ informational structure. Additionally, we introduce a labeling and indexing scheme that systematizes information-theoretic analyses of highly complex multivariate systems. Operationalizing this, we provide algorithms to directly calculate all of these quantities in closed form for finitely-modeled processes.
Statistical Mechanics (cond-mat.stat-mech), Information Theory (cs.IT), Adaptation and Self-Organizing Systems (nlin.AO)
18 pages, 6 figures; this https URL
Solving the Phase Problem of Diffraction: X-ray Standing Waves Imaging on Bismuthene/SiC(0001)
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-04-16 20:00 EDT
Niclas Tilgner, Susanne Wolff, Serguei Soubatch, Tien-Lin Lee, Fabian Göhler, F. Stefan Tautz, Thomas Seyller, Philip Schädlich, Christian Kumpf
The phase retrieval problem is a fundamental shortcoming of all diffraction-based methods, arising from the inability to measure the phase of scattered waves. The (normal incidence) X-ray standing wave (NIXSW) technique circumvents this issue by introducing a (Bragg-generated) X-ray standing wave field throughout the sample, relative to which any atomic species can be localized by probing its fluorescence or photoelectron yield. In essence, in a single measurement the complex scattering factor (i.e., its amplitude \textit{and} phase) corresponding to the used Bragg reflection is determined. Performing this for multiple Bragg reflections enables one to reconstruct the scattering density of the sample in three dimensions, straightforwardly as the Fourier sum of all measured (complex) scattering factors. Here, we utilize this technique to reveal the structural key features involved in the formation of the quantum spin Hall insulator bismuthene on silicon carbide. In this prominent example, the two-dimensional Bi layer is confined between a 4H-SiC substrate crystal and an epitaxial graphene layer. The key finding is a change in the adsorption site of the Bi atoms underneath the graphene upon hydrogenation, caused by the H-saturation of one (out of three) Si dangling bonds per unit cell. This structural change, clearly revealed by our NIXSW imaging experiment, is the key feature leading to the formation of the characteristic band structure of the 2D bismuthene honeycomb.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Five Figures, supplement with three figures
A tutorial on simulating nonlinear behaviors of flexible structures with the discrete differential geometry (DDG) method
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-04-16 20:00 EDT
Weicheng Huang, Zhuonan Hao, Jiahao Li, Dezhong Tong, Kexin Guo, Yingchao Zhang, Huajian Gao, K. Jimmy Hsia, Mingchao Liu
Flexible elastic structures, such as beams, rods, ribbons, plates, and shells, exhibit complex nonlinear dynamical behaviors that are central to a wide range of engineering and scientific applications, including soft robotics, deployable structures, and biomedical devices. While various numerical methods have been developed to simulate these behaviors, many conventional approaches struggle to simultaneously capture geometric and material nonlinearities, as well as nonlinear external interactions, particularly in highly deformable and dynamically evolving systems. The Discrete Differential Geometry (DDG) method has emerged as a robust and efficient numerical framework that intrinsically preserves geometric properties, accommodates material nonlinearity, and accurately models interactions with external environments and fields. By directly discretizing geometric and mechanical quantities, DDG provides an accurate, stable, and efficient approach to modeling flexible structures, addressing key limitations of traditional numerical methods. This tutorial provides a systematic introduction to the DDG method for simulating nonlinear behaviors in flexible structures. It covers DDG theory, simulation frameworks, and MATLAB implementation, with examples spanning dynamic systems, geometric and material nonlinearities, and external interactions like magnetics and fluids, culminating in practical insights and future directions. By offering a comprehensive and practical guide, together with open-source MATLAB code, this tutorial aims to facilitate the broader adoption of DDG-based numerical tools among researchers and engineers in computational mechanics, applied mathematics, and structural design.
Soft Condensed Matter (cond-mat.soft)
87 pages
Probing the Quantum Geometry of Correlated Metals using Optical Conductivity
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Deven P. Carmichael, Martin Claassen
Recent studies have revealed that the quantum geometry of electronic bands determines the electromagnetic properties of non-interacting insulators and semimetals. However, the role of quantum geometry in the optical responses of interacting electron systems remains largely unexplored. Here we examine the interplay between Coulomb interactions and Bloch-band quantum geometry in clean metals. We demonstrate that the low-frequency optical conductivity of a correlated metal encodes the structure of Bloch wave functions at the Fermi surface. This response originates from integrating out highly off-resonant interband scattering processes enabled by Coulomb interactions. The resulting quantum-geometric contribution appears generically in multiband systems, but becomes the dominant effect in the optical conductivity for a parabolic band. We consider a dilute correlated metal near a topological band inversion and show that the doping dependence of optical absorption can measure how the orbital character of Bloch wave functions changes at the Fermi surface. Our results illustrate how the confluence of quantum geometry and Coulomb interactions can enable optical processes and enrich the physics of Fermi liquids.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
11 pages, 5 figures, including appendix
SymTFT construction of gapless exotic-foliated dual models
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
Fabio Apruzzi, Francesco Bedogna, Salvo Mancani
We construct Symmetry Topological Field Theories (SymTFTs) for continuous subsystem symmetries, which are inherently non-Lorentz-invariant. Our framework produces dual bulk descriptions – gapped foliated and exotic SymTFTs – that generates gapless boundary theories with spontaneous subsystem symmetry breaking via interval compactification. In analogy with the sandwich construction of SymTFT, we call this Mille-feuille. This is done by specifying gapped and symmetry-breaking boundary conditions. In this way we obtain the foliated dual realizations of various models, including the XY plaquette, XYZ cube, and $ \phi$ , $ \hat{\phi}$ theories. This also captures self-duality symmetries as condensation defects and provides a systematic method for generating free theories that non-linearly realize subsystem symmetries.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th)
40 pages, 3 figures, comments welcome
Intermediate phases in $α$-RuCl$_3$ under in-plane magnetic field via interlayer spin interactions
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-04-16 20:00 EDT
$ \alpha$ -RuCl$ _3$ has attracted significant attention as a prime candidate for the spin-1/2 Kitaev spin liquid in two-dimensional honeycomb lattices. Although its ground state is magnetically ordered, the order is suppressed under a moderate in-plane magnetic field. The intermediate regime of the field has exotic behaviours, some of which are claimed to originate from a Kitaev spin liquid. In resolving debates surrounding these behaviours, the interlayer interactions in $ \alpha$ -RuCl$ _3$ have been largely overlooked due to their perceived weakness in van der Waals materials. However, near the transition, they may become significant as the field energy approaches the interlayer coupling scale. Here we investigate the effects of interlayer couplings in $ \alpha$ -RuCl$ _3$ with $ R\bar{3}$ and $ C2/m$ structures. We first examine their effects on the transition temperature ($ T_N$ ) using classical Monte Carlo simulations. We found that the interlayer couplings have minimal effects on $ T_N$ , and the different $ T_N$ between the two structures are mainly due to the anisotropy in the intralayer interactions. Focusing on the $ R{\bar 3}$ structure, we show that the nearest neighbour interlayer interaction is XXZ-type due to the symmetry, and the next nearest neighbor interaction of the Kitaev-type is crucial for the transition between two zigzag orders under an in-plane field. Furthermore, an intermediate phase with a large unit cell emerges due to the interlayer interactions. Our findings provide new insights into the exotic behaviours and sample dependence reported in $ \alpha$ -RuCl$ _3$ .
Strongly Correlated Electrons (cond-mat.str-el)
13 pages, 11 figures