CMP Journal 2025-10-08
Statistics
Nature: 15
Nature Materials: 1
Physical Review Letters: 18
Physical Review X: 1
arXiv: 64
Nature
Enzyme specificity prediction using cross attention graph neural networks
Original Paper | Biocatalysis | 2025-10-07 20:00 EDT
Haiyang Cui, Yufeng Su, Tanner J. Dean, Tianhao Yu, Zhengyi Zhang, Jian Peng, Diwakar Shukla, Huimin Zhao
Enzymes are the molecular machines of life, and a key property that governs their function is substrate specificity–the ability of an enzyme to recognize and selectively act on particular substrates. This specificity originates from the three-dimensional (3D) structure of the enzyme active site and complicated transition state of the reaction1,2. Many enzymes can promiscuously catalyze reactions or act on substrates beyond those for which they were originally evolved1,3-5. However, millions of known enzymes still lack reliable substrate specificity information, impeding their practical applications and comprehensive understanding of the biocatalytic diversity in nature. Herein, we developed a cross-attention-empowered SE(3)-equivariant graph neural network architecture named EZSpecificity for predicting enzyme substrate specificity, which was trained on a comprehensive tailor-made database of enzyme-substrate interactions at sequence and structural levels. EZSpecificity outperformed the existing machine learning models for enzyme substrate specificity prediction, as demonstrated by both an unknown substrate and enzyme database and seven proof-of-concept protein families. Experimental validation with eight halogenases and 78 substrates revealed that EZSpecificity achieved a 91.7% accuracy in identifying the single potential reactive substrate, significantly higher than that of the state-of-the-art model ESP (58.3%). EZSpecificity represents a general machine learning model for accurate prediction of substrate specificity for enzymes related to fundamental and applied research in biology and medicine.
Biocatalysis, Machine learning, Protein function predictions
A parabrachial hub for need-state control of enduring pain
Original Paper | Cellular neuroscience | 2025-10-07 20:00 EDT
Nitsan Goldstein, Amadeus Maes, Heather N. Allen, Tyler S. Nelson, Kayla A. Kruger, Morgan Kindel, Albert T. M. Yeung, Nicholas K. Smith, Jamie R. E. Carty, Lavinia Boccia, Niklas Blank, Emily Lo, Rachael E. Villari, Ella Cho, Erin L. Marble, Michelle Awh, Yasmina Dumiaty, Melissa J. Chee, Rajesh Khanna, Christoph A. Thaiss, Bradley K. Taylor, Ann Kennedy, J. Nicholas Betley
Long-term sustained pain following acute physical injury is a prominent feature of chronic pain conditions1. Populations of neurons that rapidly respond to noxious stimuli or tissue damage have been identified in the spinal cord and several nuclei in the brain2,3,4. Understanding the central mechanisms that signal ongoing sustained pain, including after tissue healing, remains a challenge5. Here we use spatial transcriptomics, neural manipulations, activity recordings and computational modelling to demonstrate that activity in an ensemble of anatomically and molecularly diverse parabrachial neurons that express the neuropeptide Y (NPY) receptor Y1 (Y1R neurons) is increased following injury and predicts functional coping behaviour. Hunger, thirst or predator cues suppressed sustained pain, regardless of the injury type, by inhibiting parabrachial Y1R neurons via the release of NPY. Together, our results demonstrate an endogenous analgesic hub at pain-responsive parabrachial Y1R neurons.
Cellular neuroscience, Diagnostic markers, Learning algorithms, Neural circuits, Neural decoding
Hotspots of human mutation point to clonal expansions in spermatogonia
Original Paper | Mutation | 2025-10-07 20:00 EDT
Vladimir Seplyarskiy, Mikhail A. Moldovan, Evan Koch, Prathitha Kar, Matthew D. C. Neville, Raheleh Rahbari, Shamil Sunyaev
In renewing tissues, mutations conferring selective advantage may result in clonal expansions1,2,3,4. In contrast to somatic tissues, mutations driving clonal expansions in spermatogonia (CES) are also transmitted to the next generation. This results in an effective increase of de novo mutation rate for CES drivers5,6,7,8. CES was originally discovered through extreme recurrence of de novo mutations causing Apert syndrome5. Here, we develop a systematic approach to discover CES drivers as hotspots of human de novo mutation. Our analysis of 54,715 trios ascertained for rare conditions9,10,11,12,13, 6,065 control trios12,14,15,16,17,18,19 and population variation from 807,162 mostly healthy individuals20 identifies genes manifesting rates of de novo mutations inconsistent with plausible models of disease ascertainment. We propose 23 genes hypermutable at loss-of-function (LoF) sites as candidate CES drivers. An extra 17 genes feature hypermutable missense mutations at individual positions, suggesting CES acting through gain of function. CES increases the average mutation rate roughly 17-fold for LoF genes in both control trios and sperm and roughly 500-fold for pooled gain-of-function sites in sperm21. Positive selection in the male germline elevates the prevalence of genetic disorders and increases polymorphism levels, masking the effect of negative selection in human populations. Despite the excess of mutations in disease cohorts for 19 LoF CES driver candidates, only 9 show clear evidence of disease causality22, suggesting that CES may lead to false-positive disease associations.
Mutation, Neurodevelopmental disorders, Rare variants
Age and gender distortion in online media and large language models
Original Paper | Communication | 2025-10-07 20:00 EDT
Douglas Guilbeault, Solène Delecourt, Bhargav Srinivasa Desikan
Are widespread stereotypes accurate1,2,3 or socially distorted4,5,6? This continuing debate is limited by the lack of large-scale multimodal data on stereotypical associations and the inability to compare these to ground truth indicators. Here we overcame these challenges in the analysis of age-related gender bias7,8,9, for which age provides an objective anchor for evaluating stereotype accuracy. Despite there being no systematic age differences between women and men in the workforce according to the US Census, we found that women are represented as younger than men across occupations and social roles in nearly 1.4 million images and videos from Google, Wikipedia, IMDb, Flickr and YouTube, as well as in nine language models trained on billions of words from the internet. This age gap is the starkest for content depicting occupations with higher status and earnings. We demonstrate how mainstream algorithms amplify this bias. A nationally representative pre-registered experiment (n = 459) found that Googling images of occupations amplifies age-related gender bias in participants’ beliefs and hiring preferences. Furthermore, when generating and evaluating resumes, ChatGPT assumes that women are younger and less experienced, rating older male applicants as of higher quality. Our study shows how gender and age are jointly distorted throughout the internet and its mediating algorithms, thereby revealing critical challenges and opportunities in the fight against inequality.
Communication, Sociology
A full-featured 2D flash chip enabled by system integration
Original Paper | Electrical and electronic engineering | 2025-10-07 20:00 EDT
Chunsen Liu, Yongbo Jiang, Boqian Shen, Shengchao Yuan, Zhenyuan Cao, Zhongyu Bi, Chong Wang, Yutong Xiang, Tanjun Wang, Haoqi Wu, Zizheng Liu, Yang Wang, Shuiyuan Wang, Peng Zhou
Two-dimensional (2D) materials have extended the device scalability1,2,3 of silicon (Si) technology and enabled fundamental innovations in device mechanisms4,5,6. Both industry7,8,9 and academia10,11,12,13, particularly in the field of integrated circuits, are pursuing integration breakthroughs to demonstrate the superiority of 2D electronics at the system level. Despite considerable integration progress on either 2D material integration11,12,13 or 2D-CMOS hybrid integration14, a system that can migrate the advantages of the device to the application is still lacking. Here we report a full-featured 2D NOR flash memory chip realized by an atomic device to chip (ATOM2CHIP) technology, which combines a superior 2D electronic device as a memory core and a powerful CMOS platform to support complex instruction control. The ATOM2CHIP blueprint includes a full-stack on-chip process and a cross-platform system design, providing a complete framework to bridge the gap from emerging device concept to an applicable chip. The full-stack on-chip process is a specially designed flow that incorporates planar integration, three-dimensional (3D) architecture and chip packaging, contributing to a high yield of 94.34% based on a full-chip test. The cross-platform system design handles both the 2D circuit design and the 2D-CMOS modules compatibility verification design, contributing to a highly complex, instruction-driven, full-featured chip with 8-bit commands and 32-bit parallelism. These results demonstrate an efficient system integration strategy that showcases the advantages of the 2D electronic system.
Electrical and electronic engineering, Electronic and spintronic devices
Somatic mutation and selection at population scale
Original Paper | Cancer epidemiology | 2025-10-07 20:00 EDT
Andrew R. J. Lawson, Federico Abascal, Pantelis A. Nicola, Stefanie V. Lensing, Amy L. Roberts, Georgios Kalantzis, Adrian Baez-Ortega, Natalia Brzozowska, Julia S. El-Sayed Moustafa, Dovile Vaitkute, Belma Jakupovic, Ayrun Nessa, Samuel Wadge, Marc F. Österdahl, Anna L. Paterson, Doris M. Rassl, Raul E. Alcantara, Laura O’Neill, Sara Widaa, Siobhan Austin-Guest, Matthew D. C. Neville, Moritz J. Przybilla, Wei Cheng, Maria Morra, Lucy Sykes, Matthew Mayho, Nicole Müller-Sienerth, Nicholas Williams, Diana Alexander, Luke M. R. Harvey, Thomas Clarke, Alex Byrne, Jamie R. Blundell, Matthew D. Young, Krishnaa T. A. Mahbubani, Kourosh Saeb-Parsy, Hilary C. Martin, Michael R. Stratton, Peter J. Campbell, Raheleh Rahbari, Kerrin S. Small, Iñigo Martincorena
As we age, many tissues become colonized by microscopic clones carrying somatic driver mutations1,2,3,4,5,6,7. Some of these clones represent a first step towards cancer whereas others may contribute to ageing and other diseases. However, our understanding of this phenomenon remains limited due to the challenge of detecting mutations in small clones. Here we introduce a new version of nanorate sequencing (NanoSeq)8, a duplex sequencing method with an error rate lower than five errors per billion base pairs, which is compatible with whole-exome and targeted capture. Deep sequencing of polyclonal samples with single-molecule sensitivity simultaneously profiles large numbers of clones, providing accurate mutation rates, signatures and driver frequencies in any tissue. Applying targeted NanoSeq to 1,042 non-invasive samples of oral epithelium and 371 blood samples from a twin cohort, we report an extremely rich selection landscape, with 46 genes under positive selection in oral epithelium, more than 62,000 driver mutations and evidence of negative selection in essential genes. High-resolution maps of selection across coding and non-coding sites are obtained for many genes: a form of in vivo saturation mutagenesis. Multivariate regression models enable mutational epidemiology studies on how exposures and cancer risk factors, such as age, tobacco or alcohol, alter the acquisition or selection of somatic mutations. Accurate single-molecule sequencing provides a powerful tool to study early carcinogenesis, cancer prevention and the role of somatic mutations in ageing and disease.
Cancer epidemiology, Cancer genomics, DNA sequencing, Molecular evolution, Mutation
Efficient and accurate search in petabase-scale sequence repositories
Original Paper | Computational platforms and environments | 2025-10-07 20:00 EDT
Mikhail Karasikov, Harun Mustafa, Daniel Danciu, Oleksandr Kulkov, Marc Zimmermann, Christopher Barber, Gunnar Rätsch, André Kahles
The amount of biological sequencing data available in public repositories is growing rapidly, forming a critical resource for biomedicine. However, making these data efficiently and accurately full-text searchable remains challenging. Here we build on efficient data structures and algorithms for representing large sequence sets1,2,3,4,5,6. We present MetaGraph, a methodological framework that enables us to scalably index large sets of DNA, RNA or protein sequences using annotated de Bruijn graphs. Integrating data from seven public sources7,8,9,10,11,12,13, we make 18.8 million unique DNA and RNA sequence sets and 210 billion amino acid residues across all clades of life–including viruses, bacteria, fungi, plants, animals and humans–full-text searchable. We demonstrate the feasibility of a cost-effective full-text search in large sequence repositories (67 petabase pairs (Pbp) of raw sequence) at an on-demand cost of around US$100 for small queries up to 1 megabase pairs (Mbp) and down to US$0.74 per queried Mbp for large queries. We show that the highly compressed representation of all public biological sequences could fit on a few consumer hard drives (total cost of around US$2,500), making it cost-effective to use and readily transportable for further analysis. We explore several practical use cases to mine existing archives for interesting associations, demonstrating the use of our indexes for integrative analyses, and illustrating that such capabilities are poised to catalyse advancements in biomedical research.
Computational platforms and environments, Data mining, Genome informatics
Sperm sequencing reveals extensive positive selection in the male germline
Original Paper | Disease genetics | 2025-10-07 20:00 EDT
Matthew D. C. Neville, Andrew R. J. Lawson, Rashesh Sanghvi, Federico Abascal, My H. Pham, Alex Cagan, Pantelis A. Nicola, Tetyana Bayzetinova, Adrian Baez-Ortega, Kirsty Roberts, Stefanie V. Lensing, Sara Widaa, Raul E. Alcantara, María Paz García, Sam Wadge, Michael R. Stratton, Peter J. Campbell, Kerrin Small, Iñigo Martincorena, Matthew E. Hurles, Raheleh Rahbari
Mutations that occur in the cell lineages of sperm or eggs can be transmitted to offspring. In humans, positive selection of driver mutations during spermatogenesis can increase the birth prevalence of certain developmental disorders1,2,3. Until recently, characterizing the extent of this selection in sperm has been limited by the error rates of sequencing technologies. Here we used the duplex sequencing method NanoSeq4 to sequence 81 bulk sperm samples from individuals aged 24-75 years. Our findings revealed a linear accumulation of 1.67 (95% confidence interval of 1.41-1.92) mutations per year per haploid genome driven by two mutational signatures associated with human ageing. Deep targeted and exome NanoSeq5 of sperm samples identified more than 35,000 germline coding mutations. We detected 40 genes (31 newly identified) under significant positive selection in the male germline that have activating or loss-of-function mechanisms and are involved in diverse cellular pathways. Most of the positively selected genes are associated with developmental or cancer predisposition disorders in children, whereas four of the genes exhibited increased frequencies of protein-truncating variants in healthy populations. We show that positive selection during spermatogenesis drives a 2-3-fold increased risk of known disease-causing mutations, which results in 3-5% of sperm from middle-aged to older individuals with a pathogenic mutation across the exome. These findings shed light on germline selection dynamics and highlight a broader increased disease risk for children born to fathers of advanced age than previously appreciated.
Disease genetics, Genome evolution, Rare variants
A ductile chromium-molybdenum alloy resistant to high-temperature oxidation
Original Paper | Mechanical properties | 2025-10-07 20:00 EDT
Frauke Hinrichs, Georg Winkens, Lena Katharina Kramer, Gabriely Falcão, Ewa M. Hahn, Daniel Schliephake, Michael Konrad Eusterholz, Sandipan Sen, Mathias Christian Galetz, Haruyuki Inui, Alexander Kauffmann, Martin Heilmaier
Even with the rapid development of renewable energy sources, improving the efficiency of energy conversion from fossil or synthetic fuels remains a challenge because, for example, combustion engines in long-range aircraft will still be needed in the upcoming decades1. Increasing their operating temperatures (1,050-1,150 °C (refs. 2,3,4)) is one option. This requires replacing single-crystalline Ni-based superalloys in the hottest sections of turbines by refractory-element-based materials, which exhibit much higher solidus temperatures beyond 2,000 °C (refs. 5,6,7). Here we introduce a single-phase Cr-36.1Mo-3Si (at.%) alloy that meets, for the first time, to our knowledge, the most important critical requirements for refractory-element-based materials: (1) relevant resistance against pesting, nitridation and scale spallation at elevated temperatures, minimum up to 1,100 °C, and (2) sufficient compression ductility at room temperature. Although strength and creep resistance in such alloys were already superior to Ni-based superalloys in several cases, oxidation/corrosion resistance, mandatory to withstand the combustion atmosphere, and ductility/toughness, needed for damage tolerance and device setting, still pose barriers for the development or application of refractory-element-based candidate materials. Any previous successful attempts to address the otherwise catastrophic oxidation of Mo and nitridation of Cr during oxidation suffered from a loss in ductility at ambient temperatures.
Mechanical properties, Metals and alloys
Southward impact excavated magma ocean at the lunar South Pole-Aitken basin
Original Paper | Geodynamics | 2025-10-07 20:00 EDT
Jeffrey C. Andrews-Hanna, William F. Bottke, Adrien Broquet, Alexander J. Evans, Gabriel Gowman, Brandon C. Johnson, James T. Keane, Janette N. Levin, Ananya Mallik, Simone Marchi, Samantha A. Moruzzi, Arkadeep Roy, Shigeru Wakita
The ancient South Pole-Aitken impact basin provides a key data point for our understanding of the evolution of the Moon, as it formed during the earliest pre-Nectarian epoch of lunar history1, excavated more deeply than any other known impact basin2,3 and is found on the lunar far side, about which less is known than the well-explored near side. Here we show that the tapering of the basin outline and the more gradual topographic and crustal thickness transition towards the south support a southward impact trajectory, opposite of that commonly assumed. A broad thorium-rich and iron-rich ejecta deposit southwest of the basin is consistent with partial excavation of late-stage magma ocean liquids. These observations indicate that thorium-rich magma ocean liquids persisted only beneath the southwestern half of the basin at the time of impact, matching predictions for the transition from a global magma ocean to a local enrichment of potassium, rare-earth elements and phosphorus (KREEP) in the near-side Procellarum KREEP Terrane. These results have important implications for the upcoming human exploration of the lunar south pole by Artemis, as proposed landing sites are now recognized to sit on the downrange rim and thorium-rich impact ejecta of the basin.
Geodynamics, Inner planets
Sex and smoking bias in the selection of somatic mutations in human bladder
Original Paper | Cancer epidemiology | 2025-10-07 20:00 EDT
Ferriol Calvet, Raquel Blanco Martinez-Illescas, Ferran Muiños, Maria Tretiakova, Elena S. Latorre-Esteves, Jeanne Fredrickson, Maria Andrianova, Stefano Pellegrini, Axel Rosendahl Huber, Joan Enric Ramis-Zaldivar, Shuyi Charlotte An, Elana Thieme, Brendan F. Kohrn, Miguel L. Grau, Abel Gonzalez-Perez, Nuria Lopez-Bigas, Rosa Ana Risques
Men are at higher risk of several cancer types than women1. For bladder cancer the risk is four times higher for reasons that are not clear2. Smoking is also a principal risk factor for several tumour types, including bladder cancer3. As tumourigenesis is driven by somatic mutations, we wondered whether the landscape of clones in the normal bladder differs by sex and smoking history. Using ultradeep duplex DNA sequencing (approximately 5,000×), we identified thousands of clonal driver mutations in 16 genes across 79 normal bladder samples from 45 people. Men had significantly more truncating driver mutations in RBM10, CDKN1A and ARID1A than women, despite similar levels of non-protein-affecting mutations. This result indicates stronger positive selection on driver truncating mutations in these genes in the male urothelium. We also found activating TERT promoter mutations driving clonal expansions in the normal bladder that were associated strongly with age and smoking. These findings indicate that bladder cancer risk factors, such as sex and smoking, shape the clonal landscape of the normal urothelium. The high number of mutations identified by this approach offers a new strategy to study the functional effect of thousands of mutations in vivo–natural saturation mutagenesis–that can be extended to other human tissues.
Cancer epidemiology, Cancer genomics, Genome informatics, Urological cancer
Quantum-amplified global-phase spectroscopy on an optical clock transition
Original Paper | Atomic and molecular interactions with photons | 2025-10-07 20:00 EDT
Leon Zaporski, Qi Liu, Gustavo Velez, Matthew Radzihovsky, Zeyang Li, Simone Colombo, Edwin Pedrozo-Peñafiel, Vladan Vuletić
Optical lattice clocks are at the forefront of precision metrology1,2,3,4,5,6, operating near a standard quantum limit set by quantum noise4,7. Harnessing quantum entanglement offers a promising route to surpass this limit8,9,10,11,12,13,14,15; however, there are practical difficulties in terms of scalability and measurement resolution requirements16,17. Here we adapt the holonomic quantum gate concept18 to develop a new Rabi-type ‘global-phase spectroscopy’ that uses the detuning-sensitive global Aharonov-Anandan phase19. With this approach, we can demonstrate quantum-amplified time-reversal spectroscopy on an optical clock transition that achieves directly measured 2.4(7) dB metrological gain and 4.0(8) dB improvement in laser noise sensitivity beyond the standard quantum limit. To this end, we introduce rotary echo to protect the dynamics from inhomogeneities in light-atom coupling and implement a laser-noise-cancelling differential measurement through symmetric phase encoding in two nuclear spin states. Our technique is not limited by measurement resolution, scales easily because of the global nature of entangling interaction and exhibits high resilience to typical experimental imperfections. We expect it to be broadly applicable to next-generation atomic clocks and other quantum sensors approaching the fundamental quantum precision limits20,21,22.
Atomic and molecular interactions with photons, Quantum metrology
KCTD10 is a sensor for co-directional transcription-replication conflicts
Original Paper | DNA damage and repair | 2025-10-07 20:00 EDT
Jake A. Kloeber, Bin Chen, Guangchao Sun, Charles S. King, Zhiquan Wang, Li Wang, Zheming Wu, Shouhai Zhu, Fei Zhao, Hongran Qin, Yaobin Ouyang, Huaping Xiao, Xinyi Tu, Jing Lu, Yanxia Jiang, Kuntian Luo, Ping Yin, Xinyan Wu, Robert W. Mutter, Jinzhou Huang, Zhenkun Lou
During DNA replication, the replisome must remove barriers and roadblocks including the transcription machinery1,2. Transcription-replication conflicts (TRCs) occur when there are collisions between the replisome and transcription machinery, and are increasingly recognized as an important source of mammalian genome instability3. How cells facilitate replisome bypass at sites of TRCs is incompletely understood. Here we show that the CUL3-KCTD10 E3 ligase senses TRCs and promotes remodelling of the RNA polymerase complex to allow replisome bypass. We found that the substrate adaptor KCTD10 interacts with the replisome and the transcription machinery and regulates both in unstressed conditions. These bivalent interactions allow KCTD10 to detect co-directional TRCs and facilitate higher-order assembly of KCTD10 complexes that recruit CUL3 to induce the ubiquitination and removal of the RNA polymerase factor TCEA2. In the absence of KCTD10, there is increased retention of TCEA2 and the RNA polymerase complex, causing an accumulation of TRCs and increased DNA damage. Our results demonstrate how replication can proceed through transcriptionally active regions, utilizing a unique bridging function of the CUL3-KCTD10 complex. These findings provide a framework for how the coordination between transcription and replication may contribute to the maintenance of genome stability.
DNA damage and repair, DNA replication, Transcription
Programmable on-chip nonlinear photonics
Original Paper | Nanoscience and technology | 2025-10-07 20:00 EDT
Ryotatsu Yanagimoto, Benjamin A. Ash, Mandar M. Sohoni, Martin M. Stein, Yiqi Zhao, Federico Presutti, Marc Jankowski, Logan G. Wright, Tatsuhiro Onodera, Peter L. McMahon
Nonlinear optics1 plays a central role in many photonic technologies, both classical2,3,4,5 and quantum6,7,8. However, the function of a nonlinear-optical device is typically determined during design and fixed during fabrication9, restricting the use of nonlinear optics to scenarios in which this inflexibility is tolerable. Here we present a photonic device with highly programmable nonlinear functionality: an optical slab waveguide with an arbitrarily reconfigurable two-dimensional distribution of χ(2) nonlinearity. The nonlinearity is realized using electric-field-induced χ(2) (refs. 10,11,12,13,14,15,16), and the programmability is engineered by massively parallel control of the electric-field distribution within the device using a photoconductive layer and optical programming with a spatial light pattern. To showcase the versatility of our device, we demonstrate spectral, spatial and spatio-spectral engineering of second-harmonic generation by tailoring arbitrary quasi-phase-matching grating structures1 in two dimensions. The programmability of the device makes it possible to perform inverse design of grating structures in situ, as well as real-time feedback to compensate for fluctuations in operating and environmental conditions. Our work shows that we can break from the conventional one-device-one-function paradigm, potentially expanding the applications of nonlinear optics to situations in which fast device reconfigurability is desirable–such as in programmable optical quantum gates and quantum light sources7,17,18,19, all-optical signal processing20, optical computation21 and adaptive structured light for sensing22,23,24.
Nanoscience and technology, Nonlinear optics, Optics and photonics
Flexible perceptual encoding by discrete gamma events
Original Paper | Neural circuits | 2025-10-07 20:00 EDT
Quentin Perrenoud, Antonio H. de O. Fonseca, Austin Airhart, James Bonanno, Rong Mao, Jessica A. Cardin
Cognitive processes underlying behaviour are linked to specific spatiotemporal patterns of neural activity in the neocortex1,2,3,4,5,6. These patterns arise from synchronous synaptic activity7 and are often analysed as oscillations, but may also display aperiodic dynamics that are not well detected. Here we develop a novel analytical method decomposing patterned activity into discrete network events and use this approach to track gamma activity (30-80 Hz) in the mouse visual cortex (V1). We find that the gamma event rate varies with arousal and individual events can cluster in brief oscillatory bouts but also occur in isolation. Individual events synchronize neural firing across layers and promote enhanced visual encoding. V1 gamma events are evoked by patterned input from the dorsal lateral geniculate nucleus (dLGN) and suppressed by optogenetic modulation of the dLGN, suggesting that they support thalamocortical integration of visual information. In behaving mice, the gamma event rate increases steadily before visually cued behavioural responses, predicting trial-by-trial performance. Suppressing V1 gamma events impairs visual detection performance, whereas evoking them elicits a behavioural response. This relationship between gamma events and behaviour is sensory modality specific and rapidly modulated by changes in task objectives. Gamma events thus support a flexible encoding of visual information according to behavioural context.
Neural circuits, Sensory processing
Nature Materials
Relativistic Mott transition in twisted WSe2 tetralayers
Original Paper | Phase transitions and critical phenomena | 2025-10-07 20:00 EDT
Liguo Ma, Raghav Chaturvedi, Phuong X. Nguyen, Kenji Watanabe, Takashi Taniguchi, Kin Fai Mak, Jie Shan
The realization of graphene has provided a bench-top laboratory for quantum electrodynamics. The low-energy excitations of graphene are two-dimensional massless Dirac fermions with opposite chiralities at the ±K valleys of the graphene Brillouin zone. It has been speculated that the electron-electron interactions in graphene could spontaneously break the chiral symmetry to induce a finite mass for Dirac fermions, which is also known as the relativistic Mott transition. However, the phenomenon has not been observed in pristine graphene because the interaction strength is insufficient. Here, we report the realization of strongly correlated artificial graphene and the observation of the relativistic Mott transition in twisted WSe2 tetralayers. Using magnetotransport, we show that the first Γ-valley moiré valence band mimics the low-energy graphene band structure. At half band filling, the system exhibits hallmarks of massless Dirac fermions, including an anomalous Landau fan originated from a π Berry phase and a square-root density dependence of the cyclotron mass. We tune the interaction across the semimetal-insulator transition by reducing the twist angle below about 2.7°. The emergent insulator is compatible with an antiferromagnetic Mott insulator. Our results open the possibility of studying strongly correlated Dirac fermions in a condensed matter system.
Phase transitions and critical phenomena, Quantum Hall, Two-dimensional materials
Physical Review Letters
Dynamical Response of Viscous Objects to Gravitational Waves
Article | Cosmology, Astrophysics, and Gravitation | 2025-10-08 06:00 EDT
Valentin Boyanov, Vitor Cardoso, Kostas D. Kokkotas, and Jaime Redondo-Yuste
A neutron star's viscosity determines how the star interacts with gravitational waves, a behavior that could be useful to the study of neutron-star interiors.
Phys. Rev. Lett. 135, 151402 (2025)
Cosmology, Astrophysics, and Gravitation
Ab Initio Study of the Radii of Oxygen Isotopes
Article | Nuclear Physics | 2025-10-08 06:00 EDT
Zhengxue Ren, Serdar Elhatisari, and Ulf-G. Meißner
We present an ab initio study of the charge and matter radii of oxygen isotopes from to using nuclear lattice effective field theory (NLEFT) with high-fidelity chiral interactions. To efficiently address the Monte Carlo sign problem encountered in nuclear radius calculations, we introdu…
Phys. Rev. Lett. 135, 152502 (2025)
Nuclear Physics
Precision Mass Measurements around $^{84}\mathrm{Mo}$ Rule Out ZrNb Cycle Formation in the Rapid Proton-Capture Process at Type I X-Ray Bursts
Article | Nuclear Physics | 2025-10-08 06:00 EDT
S. Kimura et al.
The rapid proton-capture process is one of the primary, explosive thermonuclear burning processes that drive type I x-ray bursts. A possible termination of the rapid proton-capture process at around was previously suggested by the formation of a ZrNb cycle. We report here precision mass measure…
Phys. Rev. Lett. 135, 152701 (2025)
Nuclear Physics
Parity-Doubled Nucleons Can Rapidly Cool Neutron Stars
Article | Nuclear Physics | 2025-10-08 06:00 EDT
Liam Brodie and Robert D. Pisarski
In confined hadronic matter, the spontaneous breaking and restoration of chiral symmetry can be described by considering nucleons, , and excited states of opposite parity, . In a cold, dense hadronic phase where chiral symmetry remains spontaneously broken, direct Urca decay processes…
Phys. Rev. Lett. 135, 152702 (2025)
Nuclear Physics
Maximum Dissipation Reduction in Bulk Polymeric Turbulence
Article | Physics of Fluids, Earth & Planetary Science, and Climate | 2025-10-08 06:00 EDT
Yi-Bao Zhang, Feng Wang, Sheng-Hong Peng, and Heng-Dong Xi
New experiments show that adding polymers to a fluid can reduce energy dissipation by suppressing small eddies.
Phys. Rev. Lett. 135, 154001 (2025)
Physics of Fluids, Earth & Planetary Science, and Climate
Droplets Wicking in Thin Materials Exhibit Universal Drying Dynamics
Article | Physics of Fluids, Earth & Planetary Science, and Climate | 2025-10-08 06:00 EDT
Garam Lee, Samira Shiri, and James C. Bird
When a drop contacts and absorbs in a thin porous surface, it can wick radially outward. This phenomenon is exploited in cooling textiles, but also complicates forensic stain analysis. The distance that the liquid spreads and the time it takes to evaporate are coupled, yet the consequence of this co…
Phys. Rev. Lett. 135, 154002 (2025)
Physics of Fluids, Earth & Planetary Science, and Climate
Voltage-Tuned Anomalous-Metal to Metal Transition in Hybrid Josephson Junction Arrays
Article | Condensed Matter and Materials | 2025-10-08 06:00 EDT
S. Sasmal, M. Efthymiou-Tsironi, G. Nagda, E. Fugl, L. L. Olsen, F. Krizek, C. M. Marcus, and S. Vaitiekėnas
We report on voltage-tuned phase transitions in arrays of hybrid semiconductor-superconductor islands arranged in a square lattice. A double-layer electrostatic gate geometry enables independent tuning of interisland coupling and proximity-induced superconductivity. This design enables access to the…
Phys. Rev. Lett. 135, 156301 (2025)
Condensed Matter and Materials
Bridging-Induced Phase Separation and Loop Extrusion Drive Noise in Chromatin Transcription
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-10-08 06:00 EDT
Michael Chiang, Cleis Battaglia, Giada Forte, Chris A. Brackley, Nick Gilbert, and Davide Marenduzzo
Cell-to-cell heterogeneity in transcription, or transcriptional noise, is important in cellular development and in disease. The molecular mechanisms driving it are, however, elusive and ill-understood. Here, we use computer simulations to explore the role of 3D chromatin structure in driving transcr…
Phys. Rev. Lett. 135, 158401 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Scalable and Modular Generation of $W$-State Entanglements via Memory-Enhanced Fusion
Article | Quantum Information, Science, and Technology | 2025-10-07 06:00 EDT
Jixuan Shi, Sheng Zhang, Yukai Wu, Yuedong Sun, Yibo Liang, Hai Wang, Yunfei Pu, and Luming Duan
Efficient generation of large-scale multipartite entangled states is a critical but challenging task in quantum information processing. Although generation of multipartite entanglement within a small set of individual qubits has been demonstrated, further scale-up in system size requires the connect…
Phys. Rev. Lett. 135, 150802 (2025)
Quantum Information, Science, and Technology
Emergence of a Landau Level Structure in Dark Optical Lattices
Article | Atomic, Molecular, and Optical Physics | 2025-10-07 06:00 EDT
Sylvain Nascimbene and Jean Dalibard
An optical flux lattice is a set of light beams that couple different internal states of an atom, thereby producing topological energy bands. Here we present a configuration in which the atoms exhibit a dark state, i.e., an internal state that is not coupled to the light. At large light intensity, t…
Phys. Rev. Lett. 135, 153402 (2025)
Atomic, Molecular, and Optical Physics
High-Efficiency Plasma-Based Compressor for Ultrafast Soft X-Ray Free-Electron Lasers
Article | Plasma and Solar Physics, Accelerators and Beams | 2025-10-07 06:00 EDT
Mingchang Wang, Li Zeng, Bingbing Zhang, Qinghao Zhu, Xiaozhe Shen, Xiaofan Wang, Qinming Li, and Weiqing Zhang
The generation of intense, femtosecond-scale x-ray pulses is crucial for probing matter under extreme temporal and field conditions. Current chirped-pulse amplification (CPA) techniques in free-electron lasers (FELs), however, face efficiency limitations in the soft x-ray regime due to the inherent …
Phys. Rev. Lett. 135, 155001 (2025)
Plasma and Solar Physics, Accelerators and Beams
Intra-Unit-Cell Singlet Pairing Mediated by Altermagnetic Fluctuations
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Yi-Ming Wu, Yuxuan Wang, and Rafael M. Fernandes
We investigate the superconducting instabilities induced by altermagnetic fluctuations. Because of the nontrivial sublattice structure of the altermagnetic order, shorter-range and longer-range fluctuations favor qualitatively different types of pairing states. Specifically, while the latter stabili…
Phys. Rev. Lett. 135, 156001 (2025)
Condensed Matter and Materials
Transparency of Graphene to Solid-Solid van der Waals Interactions
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Chuanli Yu, Weijia Zeng, Zepu Kou, Wenxiang Wang, Ling Wang, Qunyang Li, Xiaofei Liu, and Zhaohe Dai
Experiments clarify the degree to which a graphene coating can reduce the strength of van der Waals interactions with a surface.
Phys. Rev. Lett. 135, 156202 (2025)
Condensed Matter and Materials
Altermagnetism in Modified Lieb Lattice Hubbard Model
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Nitin Kaushal and Marcel Franz
We study the emergence of altermagnetism from repulsive interactions for electrons on the Lieb lattice as a model of quasi-2D oxychalcogenides with the so-called "" lattice structure. A comprehensive study of the Lieb lattice Hubbard model, using unrestricted Hartree-Fock and exact diagonal…
Phys. Rev. Lett. 135, 156502 (2025)
Condensed Matter and Materials
Artificial Gauge Field Engineered Excited-State Topology: Control of Dynamical Evolution of Localized Spinons
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Jie Ren, Yi-Ran Xue, Run-Jia Luo, Rui Wang, and Baigeng Wang
Spinons are elementary excitations at the core of frustrated quantum magnets. Although it is well established that a pair of spinons can emerge from a magnon via deconfinement, controlled manipulation of individual spinons and direct observation of their deconfinement remain elusive. We propose an a…
Phys. Rev. Lett. 135, 156601 (2025)
Condensed Matter and Materials
Large Orbital Torque from Interfacial Spin-Vorticity Coupling in PtCo/Cu Heterostructures
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Longwen Yi, Tianxiang Yang, Cheng Tan, Ronghuan Xie, Senmiao Liu, Li Cai, Qiang Cao, Yan Wang, Weiming Lü, Yufeng Tian, QiKun Huang, and Shishen Yan
The use of orbital torques to efficiently modulate magnetization is currently a central topic in orbitronics. In this Letter, we report the discovery of an unexpectedly large dampinglike torque efficiency per unit electric field in metallic heterostructures, with its maximum value being 2 (1…
Phys. Rev. Lett. 135, 156702 (2025)
Condensed Matter and Materials
Prediction of Room Temperature Ferroelectricity in Subnano Silicon Thin Films with an Antiferroelectric Ground State
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Hongyu Yu, Shihan Deng, Haiyan Zhu, Muting Xie, Yuwen Zhang, Xizhi Shi, Jianxin Zhong, Chaoyu He, and Hongjun Xiang
Recent advancements highlight the critical need for ferroelectric (FE) materials compatible with silicon, particularly pure silicon phases exhibiting FE behavior above room temperature that can be readily integrated onto silicon substrates. Here, we systematically predict potential FE silicon films …
Phys. Rev. Lett. 135, 156801 (2025)
Condensed Matter and Materials
Surface-Mediated Ultrastrong Cavity Coupling of Two-Dimensional Itinerant Electrons
Article | Condensed Matter and Materials | 2025-10-07 06:00 EDT
Christian J. Eckhardt, Andrey Grankin, Dante M. Kennes, Michael Ruggenthaler, Angel Rubio, Michael A. Sentef, Mohammad Hafezi, and Marios H. Michael
Engineering phases of matter in cavities requires effective light-matter coupling strengths that are on the same order of magnitude as the bare system energetics, coined the ultrastrong coupling regime. For models of itinerant electron systems, which do not have discrete energy levels, a clear defin…
Phys. Rev. Lett. 135, 156902 (2025)
Condensed Matter and Materials
Physical Review X
Experimental Signatures of a New Channel of the Deuteron-Deuteron Reaction at Very Low Energy
Article | | 2025-10-07 06:00 EDT
R. Dubey, K. Czerski, Gokul Das H., A. Kowalska, N. Targosz-Sleczka, M. Kaczmarski, and M. Valat
Deuteron-deuteron fusion at energies below 5 keV occurs mainly via a helium-4 resonance that decays by emitting electron-positron pairs, a newly observed, dominant reaction channel important for stellar nucleosynthesis and fusion models.
Phys. Rev. X 15, 041004 (2025)
arXiv
Vestigial $d$-wave charge-$4e$ Superconductivity from Bidirectional Pair Density Waves
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
We analyze the leading vestigial instability due to the melting of a bidirectional pair-density-wave state in two dimensions. In a previous work by one of the authors, it was found that the interplay between pair-density-wave fluctuations with ordering momenta along the $ x$ and $ y$ directions can provide a strong attractive interaction for charge-$ 4e$ superconductivity in the $ d$ -wave channel. In this work, we go beyond the artificial large-$ M$ mean-field theory previously adopted and compute the phase diagram by incorporating phase fluctuations of the pair-density-wave order parameters. By investigating the relevance of various topological defects, we show that the interaction in the $ d$ -wave channel, together with the strong anisotropy of phase fluctuations around the pair-density-wave ordering momenta, favors a vestigial charge-$ 4e$ superconducting order at intermediate temperatures. By contrast, a competing charge-density-wave vestigial order does not develop, due to the suppression of its stiffness.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
Effects of intertube dipole-dipole interactions in nearly integrable one-dimensional $^{162}$Dy gases
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-08 20:00 EDT
Yicheng Zhang, Kangning Yang, Benjamin L. Lev, Marcos Rigol
We study the effects of the intertube dipole-dipole interactions (DDI) in recent experiments with arrays of nearly integrable one-dimensional (1D) dipolar Bose gases of $ ^{162}$ Dy atoms. An earlier theoretical modeling ignored those interactions, which we include here via a modification of the 1D confining potentials. We investigate the effects of the intertube DDI both during the state preparation and during the measurements of the rapidity distributions. We explore how the strength of the contact interactions and the magnetic field angles modify the intertube DDI corrections. We find that those corrections slightly change both the properties of the equilibrium state and the rapidity measurements. Remarkably, however, the changes nearly cancel each other, resulting in measured rapidity distributions that are very close to those predicted in the absence of the intertube DDI.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
10 pages, 11 figures
Scalable accuracy gains from postselection in quantum error correcting codes
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-08 20:00 EDT
Hongkun Chen, Daohong Xu, Grace M. Sommers, David A. Huse, Jeff D. Thompson, Sarang Gopalakrishnan
Decoding stabilizer codes such as the surface and toric codes involves evaluating free-energy differences in a disordered statistical mechanics model, in which the randomness comes from the observed pattern of error syndromes. We study the statistical distribution of logical failure rates across observed syndromes in the toric code, and show that, within the coding phase, logical failures are predominantly caused by exponentially unlikely syndromes. Therefore, postselecting on not seeing these exponentially unlikely syndrome patterns offers a scalable accuracy gain. In general, the logical error rate can be suppressed from $ p_f$ to $ p_f^b$ , where $ b \geq 2$ in general; in the specific case of the toric code with perfect syndrome measurements, we find numerically that $ b = 3.1(1)$ . Our arguments apply to general topological stabilizer codes, and can be extended to more general settings as long as the decoding failure probability obeys a large deviation principle.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
17 pages, 11 figures
Superfluid weight in disordered flat-band superconductors as a competition between localization functionals
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-08 20:00 EDT
Kryštof Kolář, Tero T. Heikkilä, Päivi Törmä
According to Anderson’s theorem, the gap of a time-reversal symmetric weak-coupling superconductor is unaffected by non-magnetic disorder. However, the superfluid weight (stiffness) is reduced in the disordered limit by a factor of $ \Delta \tau$ , a product of the scattering time $ \tau$ and the superconducting order parameter $ \Delta$ . Here we show that the opposite holds true in flat-band superconductors. While non-magnetic disorder does reduce the order parameter, we find that its direct effect on superfluid weight is mostly negligible. We show analytically that the effect of disorder is to lowest order given in terms of the difference between the intraband and interband parts of the localization functional of impurity wavefunctions, finding it to be typically vanishing.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
5 pages + Supplementary
Spin-spiral instability of the Nagaoka ferromagnet in the crossover between square and triangular lattices
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Darren Pereira, Erich J. Mueller
We study the hard-core Fermi-Hubbard model in the crossover between square and triangular lattices near half-filling. As was recognized by Nagaoka in the 1960s, on the square lattice the presence of a single hole leads to ferromagnetic spin ordering. On the triangular lattice, geometric frustration instead leads to a spin-singlet ground state, which can be associated with a 120-degree spiral order. On lattices which interpolate between square and triangular, there is a phase transition at which the ferromagnetic order becomes unstable to a spin spiral. We model this instability, finding the exact critical point.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
6 pages, 2 figures
TeMFpy: a Python library for converting fermionic mean-field states into tensor networks
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
We introduce TeMFpy, a Python library for converting fermionic mean-field states to finite or infinite matrix product state (MPS) form. TeMFpy includes new, efficient, and easy-to-understand algorithms for both Slater determinants and Pfaffian states. Together with Gutzwiller projection, these also allow the user to build variational wave functions for various strongly correlated electron systems, such as quantum spin liquids. We present all implemented algorithms in detail and describe how they can be accessed through TeMFpy, including full example workflows. TeMFpy is built on top of TeNPy and, therefore, integrates seamlessly with existing MPS-based algorithms.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con), Computational Physics (physics.comp-ph), Quantum Physics (quant-ph)
28 pages, 5 figures, 3 code listings
Boundary criticality in two-dimensional correlated topological superconductors
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Yang Ge, Huan Jiang, Hong Yao, Shao-Kai Jian
The presence of a boundary enriches the nature of quantum phase transitions. However, the boundary critical phenomena in topological superconductors remain underexplored so far. Here, we investigate the boundary criticality in a two-dimensional correlated time-reversal-invariant topological superconductor tuned through a quantum phase transition into a trivial time-reversal-breaking superconductor. Using sign-problem-free determinant quantum Monte Carlo simulations, we chart the quantum phase diagram and reveal the boundary criticalities encompassing ordinary, special, and extraordinary transitions. Additionally, using renormalization group analysis, we compute the boundary critical exponent up to two loops. Remarkably, the simulations and two-loop renormalization group calculations consistently demonstrate that the presence of the boundary Majorana fermion at the special transition gives rise to a new type of boundary Gross-Neveu-Yukawa fixed point. We conclude with a discussion of possible experimental realizations in iron-based superconductors.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
7+4 pages, 3+4 figures, 1 table
Emergence of nematic loop-current bond order in vanadium Kagome metals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
The family of layered Kagome metals $ \mathrm{A}\mathrm{V}_3\mathrm{Sb}_5$ $ (\mathrm{A}=\mathrm{K,Rb,Cs})$ has recently attracted significant interest due to reports of charge-bond order, orbital magnetism, and superconductivity. Some of these phases may exhibit time-reversal symmetry breaking, as suggested by their response to magnetic fields. More recently, experiments have reported the emergence of nematic order that lowers the rotational symmetry of the system from sixfold to twofold. Here we investigate the mechanism behind a nematic phase that breaks both rotational and time-reversal symmetries. Starting from a nine-band tight-binding model and nearest-neighbour Coulomb interactions, we find nematic order to emerge in a narrow region of phase space within mean-field theory. The nematic state is a superposition of charge-bond order along one Kagome bond and loop-current order on the other two, preserving one of the three mirror planes. To understand this behaviour, we examine an effective patch model that captures one $ p$ -type and one $ m$ -type van Hove singularity at each $ M$ point on the Brillouin zone boundary. Within the effective model, nematic order is stabilized by the coupling between the complex phases of the three bond order parameters. As a consequence, the nematic phase develops an elongated Fermi surface distinct from those of competing phases.
Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 10 figures
Variational and field-theoretical approach to exciton-exciton interactions and biexcitons in semiconductors
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Peter A. Noordman, Lucas Maisel Licerán, Henk T. C. Stoof
Bound electron-hole pairs in semiconductors known as excitons are the subject of intense research due to their potential for optoelectronic devices and applications, especially in the realm of two-dimensional materials. While the properties of free excitons in these systems are well understood, a general description of their interactions is complicated due to their composite nature, which leads to exchange between the identical fermions of different excitons. In this work we employ a variational approach to study interactions between Wannier excitons and obtain an effective interaction potential between two ground-state excitons in a system of spin-degenerate electrons and holes. This potential is in general nonlocal and depends on the coupled spins of the particles. When particularized to hydrogen-like excitons with a heavy hole, it becomes local and exactly reproduces the Heitler-London result for two interacting hydrogen atoms. Thus, our result can be interpreted as a generalization of the Heitler-London potential to arbitrary masses. Including corrections due to excited states results in a van der Waals potential at large distances, which is expected due to the induced dipole-dipole nature of the interactions. Additionally, we use a path-integral formalism to develop a many-body theory for a gas of excitons, resulting in an excitonic action that formally includes many-body interactions between excitons. While in the field representing the excitons is exactly bosonic, we clarify how the internal exchange processes arise in the field-theoretical treatment, and show that the diagrams corresponding to the interactions between excitons align with our variational calculation when evaluated on shell. Our methods and results lay the groundwork for a generalized theory of exciton-exciton interactions and their application to the study of biexciton spectra and correlated excitonic matter.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
Semiconductor Meta-Graphene and Valleytronics
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Praveen Pai, Aron W. Cummings, Alexander Cerjan, Wei Pan, Fan Zhang, Catalin D. Spataru
Nano-patterned semiconductor interfaces offer a versatile platform for creating quantum metamaterials and exploring novel electronic phenomena. In this study, we illustrate this concept using artificial graphene–a metamaterial featuring distinctive properties including Dirac and saddle points. We demonstrate that introducing additional nano-patterning can open a Dirac band gap, giving rise to what we term artificial hexagonal boron nitride (AhBN). The calculated valley Chern number of AhBN indicates the presence of topological valley Hall states confined to Dirac-gap domain walls. A key question is whether these one-dimensional edge states are topologically protected against disorder, given their vulnerability to Anderson localization. To this end, we perform band structure and electronic transport simulations under experimentally relevant disorder, including charge puddles and geometric imperfections. Our results reveal the resilience of the domain wall states against typical experimental disorder, particularly while the AhBN band gap remains open. The localization length along the domain wall can reach several microns–several times longer than the bulk electron mean free path–even though the number of bulk transport channels is greater. To enhance the effectiveness of the low-dissipation domain wall channel, we propose ribbon geometries with a large length-to-width ratio. These findings underscore both the potential and challenges of AhBN for low-energy, power-efficient microelectronic applications.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Topological Protection in a Landau Flat Band at $ν=7/11$, a Candidate Filling Factor for Unconventional Correlations
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Waseem Hussain, Haoyun Huang, Loren N. Pfeiffer, Kenneth W. West, Kirk. W. Baldwin, Gábor A. Csáthy
Strong interactions in Landau flat bands are known to stabilize correlated states that do not form in other types of flat bands. We report hallmarks of topological protection at the Landau level filling factor v=7/11 in a two-dimensional electron system. The $ \nu=7/11$ filling factor is the particle-hole conjugate of $ \nu=4/11$ , a filling factor intensely studied for the possibility of realizing unconventional electronic correlations. Our data establishes a new instance for an unusual fractional quantum Hall state and opens up possibilities for the study of unconventional correlations in an enlarged parameter space. We report and discuss transport signatures developing at other filling factors of interest $ \nu= 11/17$ , $ 5/8$ , and $ 8/13$ , which however in our sample do not exhibit topological protection.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
PNAS Nexus, Volume 4, Issue 8, pgaf254 (2025)
Tunable electronic energy level alignment and exciton diversity in organic-inorganic van der Waals heterostructures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Aurélie Champagne, Olugbenga Adeniran, Jonah B. Haber, Antonios M. Alvertis, Zhen-Fei Liu, Jeffrey B. Neaton
van der Waals stacking of two-dimensional (2D) materials offers a powerful platform for engineering material interfaces with tailored electronic and optical properties. While most van der Waals multilayers have featured inorganic monolayers, incorporating molecular monolayers introduces new degrees of tunability and functionality. Here, we investigate hybrid bilayers composed of atomically thin perylene-based molecular crystals interfaced with monolayer transition metal dichalcogenides (TMDs), specifically MoS2 and WS2. Using ab initio many-body perturbation theory within the GW approximation and the Bethe-Salpeter equation approach, we predict emergent properties beyond those of the isolated constituent systems. Notably, we find substantial renormalization of monolayer molecular crystal band gap due to TMD-induced polarization. Furthermore, by varying the TMD monolayer, we demonstrate tuning of the energy level alignment of the bilayer and subsequent control over a diversity of lowest-energy excitons, which include strongly bound hybrid excitons and long-lived charge-transfer excitons. These findings establish organic-inorganic van der Waals heterostructures as a promising class of materials for tunable optoelectronic devices and quantum excitonic phenomena, expanding the design space for low-dimensional systems.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph), Computational Physics (physics.comp-ph)
23 pages, 5 figures
Switchable spin-photon coupling with hole spins in single-quantum dots
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Carlos Sagaseta, María José Calderón, José Carlos Abadillo-Uriel
Spin qubits in semiconductor quantum dots offer a gate-tunable platform for quantum information processing. While two-qubit interactions are typically realized through exchange coupling between neighboring spins, coupling spin qubits to photons via hybrid spin-cQED devices enables long-range interactions and integration with other cQED platforms. Here, we investigate hole spin-photon coupling in compact single quantum dot setups. By incorporating ubiquitous strain inhomogeneities to our theory, we identify three main spin-photon coupling channels: a vector-potential-spin-orbit geometric mechanism–dominant for vertical magnetic fields–, an inhomogeneous Rashba term generalizing previous spin-orbit field models, and strain-induced $ g$ -tensor terms–most relevant for in-plane fields. Comparing Si, unstrained (relaxed) Ge, and biaxially strained Ge wells, we find that Si and unstrained Ge provide optimal coupling strengths (tens of MHz) thanks to their reduced heavy-hole, light-hole splitting. We demonstrate efficient switching of the spin-photon coupling while preserving sweet spot operation. Finally, we evaluate quantum state transfer and two-qubit gate protocols, achieving $ >99%$ fidelity for state transfer and $ >90%$ for two-qubit gates with realistic coherence times, establishing single-dot hole spins as a viable platform for compact spin-cQED architectures and highlighting unstrained Ge as a promising candidate for spin-photon interactions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages + 5 figures + appendices
Fermi surface and Berry phase analysis for Dirac nodal line semimetals: cautionary tale to SrGa$_2$ and BaGa$_2$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Yuxiang Gao, Yichen Zhang, Shiming Lei, Neil Harrison, Mun Keat Chan, Jonathan D. Denlinger, Sergey Gorovikov, Sanu Mishra, Yan Sun, Ming Yi, Emilia Morosan
A Berry phase of odd multiples of $ \pi$ inferred from quantum oscillations (QOs) has often been treated as evidence for nontrivial reciprocal space topology. However, disentangling the Berry phase values from the Zeeman effect and the orbital magnetic moment is often challenging. In centrosymmetric compounds, the case is simpler as the orbital magnetic moment contribution is negligible. Although the Zeeman effect can be significant, it is usually overlooked in most studies of QOs in centrosymmetric compounds. Here, we present a detailed study on the non-magnetic centrosymmetric $ \mathrm{SrGa_2}$ and $ \mathrm{BaGa_2}$ , which are predicted to be Dirac nodal line semimetals (DNLSs) based on density functional theory (DFT) calculations. Evidence of the nontrivial topology is found in magnetotransport measurements. The Fermi surface topology and band structure are carefully studied through a combination of angle-dependent QOs, angle-resolved photoemission spectroscopy (ARPES), and DFT calculations, where the nodal line is observed in the vicinity of the Fermi level. Strong de Haas-van Alphen fundamental oscillations associated with higher harmonics are observed in both compounds, which are well-fitted by the Lifshitz-Kosevich (LK) formula. However, even with the inclusion of higher harmonics in the fitting, we found that the Berry phases cannot be unambiguously determined when the Zeeman effect is included. We revisit the LK formula and analyze the phenomena and outcomes that were associated with the Zeeman effect in previous studies. Our experimental results confirm that $ \mathrm{SrGa_2}$ and $ \mathrm{BaGa_2}$ are Dirac nodal line semimetals. Additionally, we highlight the often overlooked role of spin-damping terms in Berry phase analysis.
Materials Science (cond-mat.mtrl-sci)
15 pages, 13 figures
Thermodynamics of proton insertion across the perovskite-brownmillerite transition in La0.5Sr0.5CoO3-δ
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Armand J. Lannerd, Nathan J. Szymanski, Christopher J. Bartel
La$ _{1-x}$ Sr$ _{x}$ CoO3-$ \delta$ is a promising off-stoichiometric metal oxide that undergoes a topotactic perovskite ($ \delta$ = 0) to brownmillerite ($ \delta$ = 0.5) transition under electrochemical and thermochemical stimuli, with concomitant variations in its electrical, magnetic, thermal, and optical properties. Recent studies on thin-film cycling in electrochemical devices show incomplete reversibility of this transition, with significant acid-etching serving as a degradation mechanism. While earlier investigations examined the protonation of brownmillerite SrCoO2.5, the thermodynamics of protonation across the perovskite-to-brownmillerite transition remain poorly understood. In this work, we combine density functional theory calculations with predictions from universal machine-learning interatomic potentials to elucidate the energetics and implications of protonation across the transition for La0.5Sr0.5CoO3-$ \delta$ . These calculations reveal negative hydrogen insertion energies and strong competition with oxygen vacancy formation across the transition for a wide range of conditions. The extent of protonation is primarily limited by the availability of Co 3d states to accommodate reduction by inserted hydrogen. Although hydrogen insertion is often thermodynamically favorable within a defect picture, a convex hull analysis of the resulting HyLa0.5Sr0.5CoO3-$ \delta$ phases reveals them to be unstable against decomposition into hydroxides among other products. This instability increases with hydrogen content and provides a thermodynamic basis for the acid-etching observed during electrochemical cycling. This work advances the fundamental understanding of protonation in La0.5Sr0.5CoO3-$ \delta$ and contextualizes experimental observations of related materials in the presence of moisture or H2.
Materials Science (cond-mat.mtrl-sci)
Cation vacancies mediate thermochemical water splitting with iron aluminates
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Nathan J. Szymanski, Kent J. Warren, Alan W. Weimer, Christopher J. Bartel
Solar thermochemical water splitting enables hydrogen production by cycling metal oxides between reduced and oxidized states, typically through an oxygen vacancy mechanism. However, recent experimental work suggests that cation vacancies have a greater influence on the redox behavior of iron aluminate spinels used in water splitting. This remains debated, as calculations predict that such cation vacancies are thermodynamically unfavorable. In the current work, we show that Fe vacancies in (Fe$ \zeta$ Al1-$ \zeta$ )3O4 become accessible only when facilitated by inversion between Fe and Al. This antisite disorder lowers the formation energy of octahedral Fe vacancies in Al-rich spinels ($ \zeta$ = 1/3) from over 3 eV to just 0.62 eV when one third of the cation sites are inverted, allowing high Fe vacancy concentrations under oxidizing conditions. This mechanism supports high H2 yields up to 361 $ \mu$ mol/g, consistent with experimental observations. Our findings support the notion that solar thermochemical water splitting can occur through a cation vacancy mechanism. They also clarify how site inversion, vacancy energetics, and defect interactions each contribute to redox performance, offering general design principles for identifying and optimizing materials that operate through cation vacancy cycling.
Materials Science (cond-mat.mtrl-sci)
Machine Learning Interatomic Potentials Enable Molecular Dynamics Simulations of Doped MoS2
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
We present the first computational framework for molecular dynamics simulation of MoS2 doped with 25 elements spanning metals, non-metals, and transition metals using Meta’s Universal Model for Atoms machine learning interatomic potential (MLIP). Benchmarking against density functional theory calculations demonstrates the accuracy of the MLIP for simulating doped-MoS2 systems and highlights opportunities for improvement. Using the MLIP, we perform heating-cooling simulations of doped-MoS2 supercells. The simulations capture complex phenomena including dopant clustering, MoS2 layer fracturing, interlayer diffusion, and chemical compound formation at orders-of-magnitude reduced computational cost compared to density functional theory. This work provides an open-source computational workflow for application-oriented design of doped-MoS2, enabling high-throughput screening of dopant candidates and optimization of compositions for targeted tribological, electronic, and optoelectronic performance. The MLIP bridges the accuracy-efficiency gap between first-principles methods and empirical potentials, and the framework offers unprecedented opportunities for large-scale materials discovery in two-dimensional doped material systems.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Exact Quench Dynamics from Thermal Pure Quantum States
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-08 20:00 EDT
We present an exact solution for a quantum quench in an integrable system that reveals a new, coherent pathway to thermalization. In chaotic systems, thermalization is understood via the eigenstate thermalization hypothesis (ETH), which implies that a quench from a thermal pure quantum (TPQ) state should exhibit trivial dynamics. In contrast, integrable systems are expected to retain memory of their initial conditions in a non-thermal generalized Gibbs ensemble (GGE). We show that a quench from a TPQ state in the integrable spin-1/2 XX chain defies both expectations. The system thermalizes to a canonical Gibbs ensemble, yet the entanglement dynamics are highly non-trivial, exhibiting a “double plateau” structure. We solve this process exactly using techniques in two-dimensional (2D) conformal field theories (CFT), an exact numerical method based on the matrix Riccati equation, and an asymptotically exact quasiparticle picture. We prove that the non-trivial dynamics are the macroscopic signature of the coherent dephasing of the initial state’s anomalous pairing correlations.
Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
5+16 pages, 1 figure
Dynamics of quantum measurement via electron transport in quantum dot systems: many-particle wavefunction approach
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
George Stavisskii, Leonid Fedichkin
Measurement of a charge qubit via point contacts with complex internal structures is considered. In this context, a fully formalized derivation of the many-body wave function method is presented, together with the corresponding master equations for point contacts possessing an arbitrary number of internal states. The focus is placed on the current noise power spectrum and its dependence on the qubit dynamics and the point contact parameters.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
15 pages, 10 figures
Investigation of the Effect of Thermal-Induced Atomic Motion on the Conductance of Copper Thin Films
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Sihe Chen, Kevin Batzinger, Manuel Smeu
Decrease in the size of integrated circuits (IC) and metal interconnects raise resistivity due the amplification of electron scattering effects, which decreases the efficiency of chiplets. While previous studies have investigated the electron scattering due to a roughened surface, the effect of thermal induced atomic motion on the roughened surface remains unclear. To address this gap, we investigated electron transport in pristine and roughened Cu thin films by performing \textit{ab initio} molecular dynamics (AIMD) trajectories over 20ps at temperatures of 218K, 300K, and 540K on Cu thin film models, and then calculating the electron transport properties of the resulting snapshots at 100-fs intervals for the last 10~ps using the non-equilibrium Green’s function formalism in combination with density functional theory (NEGF-DFT). As expected, higher temperatures induce larger atomic displacement from their equilibrium positions and increase atomic layer separation. We also find that increase in temperature results in increased resistance (lower conductance) for the pristine film, but less so for the roughened thin film where the surface roughness itself is the main source of resistance. This study provides insights into how pristine and roughened Cu thin films behave under thermal conditions, helping researchers design better treatments to mitigate thermal effects in ICs and their metal interconnects.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Photoluminescence excitation spectroscopy of quantum wire-like dislocation states in ZnS
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Alexander Blackston, Alexandra Fonseca Montenegro, Sevim Polat Genlik, Maryam Ghazisaeidi, Roberto C. Myers
Recent \textit{ab initio} calculations predict 1D dispersive electronic bands confined to the atomic scale cores of dislocations in the wide bandgap (3.84 eV) semiconductor ZnS. We test these predictions by correlating sub-bandgap optical transitions with the density of dislocations formed during strain relaxation in epitaxial ZnS grown on GaP. The densities for four predicted partial dislocations are quantified using scanning electron microscopy-based electron channeling contrast imaging. Room-temperature ellipsometry reveals absorption peaks that scale with dislocation density and align with theoretical predictions. Low-temperature photoluminescence spectra show deep emission peaks matching dislocation 1D band-to-band transitions. Photoluminescence excitation spectroscopy reveals six distinct emission lines with contrasting excitation dependence. Four peaks (2.78, 2.41, 2.20, 1.88 eV), assigned to dislocations, exhibit only modest suppression ($ \leq$ 5$ \times$ ) when excited below the ZnS bandgap, while two other peaks (3.11, 1.53~eV) are strongly quenched ($ >$ 10$ \times$ ). These findings support the existence of efficient, 1D band-to-band radiative transitions within quantum wire-like dislocation core states in ZnS, distinct from typical non-radiative deep-level defects in wide-gap semiconductors.
Materials Science (cond-mat.mtrl-sci)
8 pages, 8 figures, 3 tables
Quantum oscillations and anisotropic magnetoresistance in the quasi-two-dimensional Dirac nodal line superconductor $\mathrm{YbSb_2}$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-08 20:00 EDT
Yuxiang Gao, Kevin Allen, Rose Albu Mustaf, Yichen Zhang, Sanu Mishra, Christopher Lane, Marta Zonno, Sergey Gorovikov, Jian-Xin Zhu, Ming Yi, Emilia Morosan
Recent interest in quantum materials has focused on systems exhibiting both superconductivity and non-trivial band topology as material candidates to realize topological or unconventional superconducting states. So far, superconductivity in most topological materials has been identified as type II. In this work, we present magnetotransport studies on the quasi-two-dimensional type I superconductor $ \mathrm{YbSb_2}$ . Combined ab initio DFT calculations and quantum oscillation measurements confirm that $ \mathrm{YbSb_2}$ is a Dirac nodal line semimetal in the normal state. The complex Fermi surface morphology is evidenced by the non-monotonic angular dependence of both the quantum oscillation amplitude and the magnetoresistance. Our results establish $ \mathrm{YbSb_2}$ as a candidate material platform for exploring the interplay between band topology and superconductivity.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
9 pages, 8 figures
Imaging Nanoscale Carrier, Thermal, and Structural Dynamics with Time-Resolved and Ultrafast Electron Energy-Loss Spectroscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Wonseok Lee, Levi D. Palmer, Thomas E. Gage, Scott K. Cushing
Time-resolved and ultrafast electron energy-loss spectroscopy (EELS) is an emerging technique for measuring photoexcited carriers, lattice dynamics, and near-fields across femtosecond to microsecond timescales. When performed in either a specialized scanning transmission electron microscope or ultrafast electron microscope (UEM), time-resolved and ultrafast EELS can directly image charge carriers, lattice vibrations, and heat dissipation following photoexcitation or applied bias. Yet recent advances in theoretical calculations and electron optics are often required to realize the full potential of ultrafast EEL spectrum imaging. In this review, we present a comprehensive overview of the recent progress in the theory and instrumentation of time-resolved and ultrafast EELS. We begin with an introduction to the technique, followed by a physical description of the loss function. We outline approaches for calculating and interpreting ground-state and transient EEL spectra spanning low-loss plasmons to core-level excitations analogous to X-ray absorption. We then survey the current state of time-resolved and ultrafast EELS techniques beyond photon-induced near-field electron microscopy, highlighting abilities to image carrier and thermal dynamics. Finally, we examine future directions enabled by emerging technologies, including electron beam monochromation, in situ and operando cells, laser-free UEM, and high-speed direct electron detectors. These advances position time-resolved and ultrafast EELS as a critical tool for uncovering nanoscale dynamic processes in quantum materials and solar energy conversion devices.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
65 Pages, 18 figures; the following article has been submitted to Chemical Physics Reviews. After it is published, it will be found at this https URL
The roles of elasticity and dimension in liquid-gel phase separation
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-08 20:00 EDT
Shichen Wang, Peter D. Olmsted
We compare six elastic models for polymer networks in the context of phase separation within a gel, including a new model that combines the finite extensible Arruda-Boyce model and the slip tube model for entangled chains. We study incompressible uniaxial stretch and compression, and three volume-changing constrained-dimension deformations, in which the material can only deform in the designated dimensions(s) while the constrained direction(s) remain(s) the same. Each model responds differently to large deformations, and our proposed model successfully describes both strain softening and strain hardening, which are both present in well-entangled elastomers. When considering phase separation, we show that the commonly-used neo-Hookean model fails to admit a common tangent construction for phase coexistence for 3D deformations. This can be resolved by using a model with finite extension, such as the Arruda-Boyce model. In constrained-dimension deformations, where the gel’s volume is allowed to change, for elastic models in which phase coexistence is possible, the critical temperatures increases and the critical concentration decreases with increasing deformation dimensions. This strong dependence of the phase diagram on spatial dimension and geometry distinguishes phase separation elastic media from conventional phase separation.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
Unveiling the physical attributes of CdGa2Te4 and ZnGa2Te4 compounds: A first-principles study for next-generation photovoltaics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Md Hasan Shahriar Rifat, Tanvir Khan, Md Arafat Hossain Shourov, Md Sahat Bin Sayed, Md Saiful Islam
The electronic and optical properties of CdGa2Te4 and ZnGa2Te4 were studied using first-principles DFT calculations. Band gaps were calculated using the GGA-PBESol functional. Both materials show promise for photovoltaic applications because of their large, near-unity absorption efficiencies (10^4 cm^-1) in the visible region. They exhibit low exciton binding energies (18.85-26.81 meV), large Bohr radii (23-34.3 Angstrom), and moderate exciton temperatures (218-311 K), which are favorable for photovoltaic applications. Their performance as solar cells was simulated using the SCAPS-1D tool for thin-film devices with Pt/CdS/CdGa2Te4/Cu2O/Ti and Pt/CdS/ZnGa2Te4/Cu2O/Ti structures. We investigated the effects of layer thickness, donor and acceptor concentrations (shallow donors/acceptors), and defect density on device performance. The ideal absorber thickness for XGa2Te4 (X = Cd, Zn) was found to be 1000-1800 nm, and the CdS buffer layer around 150 nm. To obtain an efficiency above 20%, the defect density in the CdGa2Te4 and ZnGa2Te4 absorber layers should be kept below 1.772 x 10^13 cm^-3. The best simulations show efficiencies of 18.46% and 17.35% for CdGa2Te4- and ZnGa2Te4-based solar cells, respectively.
Materials Science (cond-mat.mtrl-sci)
33 pages, 8 figures
Surface Excess Energy Governs the Non-Monotonic Behavior of Active Diffusivity with Activity
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-08 20:00 EDT
Self-propulsion of particles is typically explained by phoretic mechanisms driven by externally imposed chemical, electric, or thermal gradients. In contrast, chemical reactions can enhance particle diffusion even in the absence of such external gradients. We refer to this increase as active diffusivity, often attributed to self-diffusiophoresis or self-electrophoresis, although these mechanisms alone do not fully account for experimental observations. Here, we investigate active diffusivity in catalytic Janus particles immersed in reactive media without imposed gradients. We show that interfacial reactions generate excess surface energy and sustained interfacial stresses that supplement thermal energy, enabling diffusion beyond the classical thermal limit. We consistently quantify this contribution using both dissipative and non-dissipative approaches, assuming that the aqueous bath remains near equilibrium. Our framework reproduces experimentally observed trends in diffusivity versus activity, including the non-monotonic behaviors reported in some systems, and agrees with data for nanometric Janus particles catalyzing charged substrates as well as vesicles with membrane-embedded enzymes driven by ATP hydrolysis. These results demonstrate that chemical reactions can induce and sustain surface-tension gradients and surface excess energy, providing design principles for tuning mobility in synthetic active matter.
Soft Condensed Matter (cond-mat.soft), Chemical Physics (physics.chem-ph)
Cryogenic growth of aluminum: structural morphology, optical properties, superconductivity and microwave dielectric loss
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-08 20:00 EDT
Wilson J. Yánez-Parreño, Teun A. J. van Schijndel, Anthony P. McFadden, Kaixuan Ji, Susheng Tan, Yu Wu, Sergey Frolov, Stefan Zollner, Raymond W. Simmonds, Christopher J. Palmstrøm
We explore the molecular beam epitaxy synthesis of superconducting aluminum thin films grown on c-plane sapphire substrates at cryogenic temperatures of 6 K and compare their behavior with films synthesized at room temperature. We demonstrate that cryogenic growth increases structural disorder, producing crystalline grains that modify the optical, electrical, and superconducting properties of aluminum. We observe that cryogenic deposition changes the color of aluminum from fully reflective to yellow and correlate the pseudo-dielectric function and reflectance with structural changes in the film. We find that smaller grain sizes enhance the superconductivity of aluminum, increasing its critical temperature and critical field. We then estimate the superconducting gap and coherence length of Cooper pairs in aluminum in the presence of disorder. Finally, we fabricate superconducting microwave resonators on these films and find that, independently of the growth temperature, the system is dominated by two-level system loss with similar quality factors in the high and low power regimes. We further measure a higher kinetic inductance in the cryogenically grown films.
Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
Full counting statistics of electron-photon hybrid systems: Joint statistics and fluctuation symmetry
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-08 20:00 EDT
Electron-photon hybrid systems serve as ideal light-matter interfaces with broad applications in quantum technologies. These systems are typically operated dynamically under nonequilibrium conditions, giving rise to coupled electronic and photonic currents. Understanding the joint fluctuation behavior of these currents is essential for assessing the performance of light-matter interfaces that rely on electron-photon correlations. Here, we investigate the full counting statistics of coupled electronic and photonic currents in an experimentally feasible hybrid system composed of a double quantum dot coupled to an optical cavity. We employ the framework of quantum Lindblad master equation which is augmented with both electronic and photonic counting fields to derive their joint cumulant generating function–a treatment that differs significantly from existing studies, which typically focus on either electron or photon statistics separately. We reveal that the ratio between photonic and electronic currents, as well as their variances, can deviate from an expected quadratic scaling law in the large electron-photon coupling regime. Furthermore, we demonstrate that conventional modelings of photonic dissipation channels in quantum master equations must be modified to ensure that the joint cumulant generating function satisfies the fluctuation symmetry enforced by the fluctuation theorem. Our results advance the understanding of joint fluctuation behaviors in electron-photon hybrid systems and may inform the design of efficient quantum light-matter interfaces.
Statistical Mechanics (cond-mat.stat-mech), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
16 pages, 6 figures, comments are welcome!
Spin Symmetry Criteria for Odd-parity Magnets
New Submission | Other Condensed Matter (cond-mat.other) | 2025-10-08 20:00 EDT
Xun-Jiang Luo, Jin-Xin Hu, K. T. Law
Inspired by the discovery of altermagnets, which exhibit even-parity nonrelativistic spin splitting, odd-parity magnets (OPMs) have been proposed and emerged as a novel research frontier. In this study, we perform a comprehensive spin group symmetry analysis to establish symmetry criteria for the emergence of OPMs. We identify eight distinct symmetry-driven cases that support OPMs, enabling their realization in collinear, coplanar, and noncoplanar magnetic orders. These OPMs are categorized into three types based on their spin textures for Bloch states: collinear (type-I), coplanar (type-II), and noncoplanar (type-III). For type-I OPMs, we further delineate additional symmetry requirements for $ p$ -wave and $ f$ -wave spin splitting. We identify 48 candidate materials in the Magndata database that satisfy these symmetry criteria. Additionally, we construct two theoretical models to validate the effectiveness of the established symmetry criteria. Finally, we show that OPMs can exhibit an intrinsic $ \mathbb{Z}_2$ topology and construct a theoretical model to realize this phase.
Other Condensed Matter (cond-mat.other)
7 pages, 2 figures
Memory behavior of a randomly driven model glass
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-08 20:00 EDT
Roni Chatterjee, Smarajit Karmakar, Muhittin Mungan, Damien Vandembroucq
We investigate by atomistic simulations the memory behavior a model glass subjected to random driving protocols. The training consists of a random walk of forward and/or backward shearing sequences bounded by a maximal shear strain of absolute value {\gamma}T . We show that such a stochastic training protocol is able to record the training amplitude. Different read-out protocols are also tested and are shown to be able to retrieve the training amplitude. We then emphasize the ten- sorial character of the memory encoded in the glass sample and then characterize the anisotropic mechanical behavior of the trained samples.
Soft Condensed Matter (cond-mat.soft), Disordered Systems and Neural Networks (cond-mat.dis-nn), Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech), Applied Physics (physics.app-ph)
yes
Probing orbital currents through inverse orbital Hall and Rashba effects
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
E. Santos, J. L. Costa, R.L. Rodriguez-Suarez, J. B. S. Mendes, A. Azevedo
We report a comprehensive experimental investigation of orbital-to-charge conversion in metallic and semiconductor materials, emphasizing the fundamental roles of the inverse orbital Hall effect (IOHE) and the inverse orbital Rashba effect. Using spin pumping driven by ferromagnetic resonance (SP-FMR) and the spin Seebeck effect (SSE), we demonstrate efficient orbital current generation and detection in YIG/Pt/NM structures, where NM is either a metal or a semiconductor. A central finding is the dominance of orbital contributions over spin-related effects, even in systems with weak spin-orbit coupling. In particular, a large enhancement of the SP-FMR and SSE signals is observed in the presence of naturally oxidized Cu in different heterostructures. Furthermore, we identify positive and negative IOHE signals in Ti and Ge, respectively, and extract orbital diffusion lengths in both systems using a diffusive model. Our results confirm the presence of orbital transport and offer valuable insights that may guide the further development of orbitronics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
25 pages, 9 figures, 1 table
Co-evaporated Formamidinium tin triiodide with suppressed p-type self-doping
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Junhyoung Park, Andrea Olivati, Mirko Prato, Min Kim, Annamaria Petrozza
Co-evaporation of formamidinium tin triiodide (FASnI3) precursors, without any additives or reducing agents, leads to the growth of a highly crystalline thin film which shows a bandgap around 1.31 eV, closely matching the theoretical value predicted from the ideal single crystal structure of FASnI3. The polycrystalline thin film presents a lower tendency of Sn2+ to Sn4+ oxidation and highly reduced tendency to self-doping, demonstrating, overall, an improved resistance to defects formation. These findings suggest solvent-free co-evaporation processes as a promising route for high quality Sn-based perovskite polycrystalline thin films.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
14 Pages, 6 figures
Engineering Magnetic States and Magnetoresistance in Bisegmented Co-Ni Jellyfish Nanowires via Interplay of Shape and Magnetocrystalline Anisotropies
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
M.I. Sobirov, K.A. Rogachev, M.A. Bazrov, Zh. Zh. Namsaraev, I.M. Sapovskii, T.R. Rakhmatullaev, N.V. Ilin, A.O Lembikov, S.M. Pisarev, A.V. Ognev, A.S. Samardak, A.Yu. Samardak
Expanding the spectrum of 3D magnetic nanostructures requires mastering the interplay between different anisotropy contributions. Here, we fabricate bisegmented jellyfish nanowires with tailored arrangements of Co (strong magnetocrystalline anisotropy) and Ni (dominant shape anisotropy) segments. We uncover a unique magnetic duality: Co segments can be tuned to exhibit either a flux-closing multidomain state or a shape-anisotropy-dominated vortex configuration, directly governed by their geometry. This local domain structure, imaged by MFM and simulated micromagnetically, dictates the global magnetic response-suppressing magnetostatic interactions in arrays and enabling the programming of the anisotropic magnetoresistance (AMR) in single nanowires. Our work provides a blueprint for designing functional magnetic nanomaterials where magnetoresistive properties are engineered through strategic anisotropy control.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
19 pages, 9 figures, 2 tables, 5 supplementary figures
From High-Entropy Ceramics (HECs) to Compositionally Complex Ceramics (CCCs) and Beyond
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Over the past decade, the field of high-entropy ceramics (HECs) has rapidly expanded to encompass a wide range of oxides, borides, silicides, and other ceramic solid solutions. In 2020, we proposed extending the concept of HECs to compositionally complex ceramics (CCCs), in which non-equimolar compositions and the presence of long- or short-range order reduce entropy while offering new opportunities to tailor and enhance properties, often beyond those of higher-entropy counterparts. Here, fundamental questions arise: Is the entropy in HECs truly high? Should maximizing entropy always be our goal? This perspective article revisits key concepts and terminologies and highlights emerging directions, including dual-phase CCCs, ultrahigh-entropy phases, and novel processing routes such as ultrafast reactive sintering. We propose that exploring compositional complexity across vast non-equimolar spaces, together with correlated disorder (coupled short-range chemical and structural orders), offers a more effective strategy for designing ceramics with superior performance than simply maximizing entropy.
Materials Science (cond-mat.mtrl-sci)
Valley-dependent topological interface states in biased armchair nanoribbons in gapless graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Zheng-Han Huang, Jing-Yuan Lai, Yu-Shu G. Wu
We investigate an electrical bias-controlled, topological kind discontinuity in valley polarization, in a two-segment armchair nanoribbon of gapless graphene, where the discontinuity is created at the interface by applying opposite in-plane, transverse electrical biases to the two segments. In particular, using an efficient tight-binding theoretical formulation, we explicitly obtain energy eigenvalues and probability distributions of discontinuity-induced, interface-confined electron eigenstates, in a reference configuration. Moreover, implications of the confinement for electron transport are explored. A configurational variation is introduced to transform the eigenstates into transport-active, quasi-localized ones. Such states are shown to result in Fano “anti-resonances” in transmission spectra. The resilience of the quasi-localized states and their associated Fano fingerprints is also illustrated with respect to configurational fluctuations, demonstrating their potential detectability in realistic devices and suggesting transport spectroscopy as a practical probe of valley-dependent topological interface physics in graphene nanoribbons.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
9 pages, and 7 figures
Liquid-gas analog multicriticality in a frustrated Ising bilayer
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
We report the discovery of a multicritical point that extends the liquid-gas paradigm to systems with competing symmetry-breaking orders. Using large-scale Monte Carlo simulations of a frustrated bilayer Ising antiferromagnet with tunable couplings, we map out a rich finite-temperature phase diagram hosting three ordered phases separated by both continuous and first-order transitions. By tuning the couplings, a tricritical line and a critical end-point line converge into a single multicritical line. At all points along the multicritical line, symmetry-distinct phases exhibit identical leading critical behavior – consistent with the tricritical Ising universality class – while the subleading exponent exhibits a sharp shift from $ y_g = 0.8$ to $ y_g = 1$ . This shift reflects an emergent $ Z_2$ symmetry akin to that of the liquid-gas critical point, but realized here at a genuine multicritical point involving simultaneous microscopic symmetry breaking. Our results establish a universality scenario in which emergent symmetry preserves the leading class but reorganizes subleading scaling, providing a general mechanism for symmetry-enforced multicriticality.
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 9 figures
Phys. Rev. B 112, 155109 (2025)
Signatures of superconducting Higgs mode in irradiated Josephson junctions
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-08 20:00 EDT
Aritra Lahiri, Juan Carlos Cuevas, Björn Trauzettel
The Higgs mode, originally proposed in the context of superconductivity, corresponds to oscillations of the amplitude of the superconducting order parameter. Recent THz-domain optical studies have found signatures consistent with the Higgs mode, but its unambiguous detection is still challenging. We predict that the existence of the Higgs mode can be unambiguously revealed by standard measurements of the transport characteristics in microwave-irradiated asymmetric and transparent Josephson junctions. One signature of the Higgs mode in a Josephson junction is the microwave-induced enhancement of the second harmonic of the equilibrium current-phase relation (at zero DC bias voltage), whose sign differs from its expected value in the absence of the Higgs mode. As the radiation frequency is varied, this enhancement exhibits resonant behavior when the microwave frequency is tuned across the Higgs mass. The second signature that we propose is the enhancement of the second harmonic of the AC Josephson current at finite DC voltage bias, which can be probed in a customary analysis of the Shapiro steps in a microwave-irradiated junction.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Giant and robust Josephson diode effect in multiband topological nanowires
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
Bao-Zong Wang, Zi-Kai Li, Zhong-Da Li, Xiong-Jun Liu
We theoretically predict the giant and robust Josephson diode effect in quasi-one-dimensional topological Majorana nanowires in the regime with multiple subbands, which is expected to be relevant for the real experiment. In the multiband regime, the Majorana bound states and conventional Andreev bound states can naturally coexist, and respectively contribute to the fractional and conventional parts in the Josephson effect, with the former/latter having 4$ \pi$ /2$ \pi$ -periodicity. We show that the interplay between the two types of bound modes can produce a robust and giant diode effect in the deep topological phase regime. Notably, we unveil a novel spin parity exchange mechanism, occurring only in the multiband regime, which leads to a robust high efficiency plateau of the giant diode effect. This effect is a nontrivial consequence of the balanced Fermi moment shifts of the multiple subbands in tuning the external magnetic field. Our finding highlights the subband engineering as a powerful tool to optimize the Josephson diode effect realistically and provides a new feasible signature to identify topological phase regime in superconducting nanowires.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
Measurement of the Quantum Capacitance Between Two Metallic Electrodes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-08 20:00 EDT
T. de Ara, B. Olivera, C. Sabater, C. Untiedt
Two factors contribute to the electrical capacitance between two electrodes: a classical contribution, stemming from the electric field, and a quantum contribution, governed by the Pauli exclusion principle, which increases the difficulty of adding charge to the electrodes. In metals, the high electronic Density of States (DOS) at the Fermi energy allows the quantum contribution to be neglected, and a classical description of the electrical capacitance between two metallic electrodes is normally used. Here, we study the evolution of the capacitance as two metallic electrodes (Pt or Au) are approached to the limit when quantum corrections are needed, before contact formation. At small distances, we observe that the classical increase in capacitance turns into saturation as the electrodes are approached, reaching the quantum capacitance limit. Finally, a capacitance leakage due to quantum tunneling is observed. Since the quantum capacitance depends on the electronic DOS on the surface of the electrodes, we use it to probe the DOS change induced by molecular adsorption (Toluene) on the metallic surface.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Dynamics of Choline Chloride based Deep Eutectic Solvents: Neutron Scattering Study
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-08 20:00 EDT
Rinesh T., H. Srinivasan, V.K. Sharma, S. Mitra
In this study, we investigate the microscopic diffusion dynamics of choline chloride (ChCl) based deep eutectic solvents (DESs) to elucidate the influence of hydrogen bond donor (HBD) identity on the mobility of cholinium ions. The DES systems examined include ethaline, glyceline, and reline, comprising ChCl mixed with ethylene glycol, glycerol, and urea, respectively, in a 1:2 molar ratio. Quasielastic neutron scattering experiments was used to probe the self-diffusion of cholinium ions at molecular length and time scales. The dynamics were modelled as a combination of jump diffusion of the molecular center of mass and localized translation within transient hydrogen-bond cages. Among the three systems, ethaline consistently exhibited the highest cholinium self-diffusion coefficients across all investigated temperatures, attributed to shorter residence times and more frequent molecular jumps. In contrast, reline displayed longer residence times with significantly larger jump length, leading to a temperature-dependent dynamical crossover: While reline and glyceline exhibited comparable diffusivities at low temperatures, reline surpassed glyceline above 330 K. These findings highlight the crucial role of HBD identity in modulating microscopic diffusion and provide valuable molecular-level insights for the rational design of DESs for targeted applications.
Soft Condensed Matter (cond-mat.soft)
Full Eigenstate Thermalization in Integrable Spin Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-08 20:00 EDT
The Eigenstate Thermalization Hypothesis(ETH) is a standard tool to understand the thermalization properties of an isolated quantum system. Its generalization to higher order correlations of matrix elements of local operators, dubbed the full ETH, predicts the decomposition of higher-order correlation function into thermal free cumulants. In this work, we numerically test these predictions of full ETH using exact diagonalization of two spin models: the Ising and the XXZ Heisenberg models. The differences from the behavior of full ETH prediction in chaotic systems are highlighted and contrasted along the way. We also show that although in these integrable spin models the dynamics of the four-time correlators, specifically the out-of-time-ordered correlator (OTOC), is encoded in the fourth order free cumulant, it exhibits late-time dynamics that is different from nonintegrable systems.
Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
7pages, 4 figures + Supplementary Material
Confinement-Controlled Morphology and Stability of One-Dimensional CrI3 Nanotubes
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Ihsan Caha, Aqrab ul Ahmad, Francis Leonard Deepak
Integrating monolayers derived from 2D van der Waals (vdW) magnetic materials into next-generation technological applications remains a significant challenge due to their structural and magnetic instability issues. Template-assisted encapsulation is a potential route for the growth of stable 2D monolayers aimed at designing novel 1D heterostructures, opening new avenues for studying low-dimensional quantum effects and spin-related phenomena. In this study, we explored the diameter-dependent encapsulation of 2D CrI3 crystals using multi-walled carbon nanotubes as nanoscale host templates. Advanced microscopic analysis revealed distinct structural transitions, ranging from internal nanorod encapsulation to external shell formation, directly influenced by the host nanotube diameter. Furthermore, statistical analysis of structural morphologies indicates that CrI3 nanorods preferentially form within MWCNTs with inner diameters up to 5 nm, while single-walled CrI3 nanotubes are stabilized in CNTs with diameters up to 8 nm. For host CNTs exceeding 10 nm in diameter, CrI3 predominantly forms surface coatings rather than confined one-dimensional structures. In situ electron beam irradiation demonstrates the superior structural stability of single-walled CrI3 confined within MWCNTs, while externally coated CrI3 undergoes decomposition into metallic Cr clusters. Prolonged irradiation induces a morphological transformation of CrI3 nanotubes into nanorods. These insights lay the groundwork for engineering robust, tunable 1D magnetic heterostructures of CrI3 for spintronic and data storage applications.
Materials Science (cond-mat.mtrl-sci)
Research article
Hidden phonon-assisted charge density wave transition in BaFe2Al9 revealed by ultrafast optical spectroscopy
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Lei Wang, Mingwei Ma, Jiangxu Li, Liucheng Chen, Bingru Lu, Xiang Li, Feng Jin, Elbert E. M. Chia, Jianlin Luo, Rongyan Chen, Peitao Liu, Fang Hong, Xinbo Wang
The interplay between electronic and lattice degrees of freedom is fundamental to charge density wave (CDW) formation, yet the microscopic origin often remains elusive. Here, we investigate the transient optical response of the intermetallic compound BaFe2Al9 using polarization-resolved ultrafast optical spectroscopy. We identify a discontinuous sign reversal in the transient reflectivity at Tc ~ 110 K, providing unambiguous evidence for the first-order transition. The anisotropic quasiparticle relaxation establishes the three-dimensional nature of the ordered state. Below Tc, a single coherent 1.6 THz oscillation appears abruptly and remains confined to the CDW phase. This mode exhibits weak temperature dependence with negligible softening and is absent in Raman spectra. First-principles calculations imply that it is a precursor phonon at the CDW wave vector with strong electron-phonon coupling. Our results indicate that the CDW in BaFe2Al9 arises from intertwined electronic and lattice instabilities, assisted by a displacive mechanism mediated by a hidden strongly coupled phonon, distinct from conventional amplitude-mode softening scenarios.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
7 pages, 4 figures
Superconducting Nanowire Single Photon Detectors based on NbRe nitride ultrafilms
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-08 20:00 EDT
F. Avitabile, F. Colangelo, M. Yu. Mikhailov, Z. Makhdoumi Kakhaki, A. Kumar, I. Esmaeil Zadeh, C. Attanasio, C. Cirillo
The influence of the reactive DC sputtering parameters on the superconducting properties of NbReN ultrathin films was investigated. A detailed study of the current-voltage characteristics of the plasma was performed to optimize the superconducting critical temperature, Tc. The thickness dependence of Tc for the films deposited under different conditions was analyzed down to the ultrathin limit. Optimized films were used to fabricate superconducting nanowire single photon detectors which, at T=3.5 K, show saturated internal detection efficiency (IDE) up to a wavelength of 1301 nm and 95% IDE at 1548 nm with recovery times and timing jitter of about 8 ns and 28 ps, respectively.
Superconductivity (cond-mat.supr-con), Instrumentation and Detectors (physics.ins-det)
accepted for publication in Applied Physics Letters
From Lasers to Photon Bose–Einstein Condensates: A Unified Description via an Open-Dissipative Bose–Einstein Distribution
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-08 20:00 EDT
Joshua Krauß, Enrico Stein, Axel Pelster
Photon condensation was first experimentally realized in 2010 within a dye-filled microcavity at room temperature. Since then, interest in the field has increased significantly, as a photon Bose-Einstein condensate (BEC) represents a prototypical driven-dissipative system. Here, we investigate how its inherent open nature influences the condensation process both quantitatively and qualitatively. To this end, we consider a mean-field model, which can be derived microscopically from a Lindblad master equation. The underlying rate equations depend on various external parameters such as emission and absorption rates of the dye molecules as well as the cavity photon loss rate. In steady state, we obtain an open-dissipative Bose-Einstein distribution for the mode occupations. The chemical potential of this distribution depends on the occupations of the dye molecules in both their ground and excited state and must therefore be determined this http URL find that the resulting photon distribution is strongly influenced by the driven-dissipative parameters. Based on this result, we identify the main differences between a photonic BEC, an atomic BEC, and a laser.
Quantum Gases (cond-mat.quant-gas)
18 pages, 6 figures
High- and medium-entropy nitride coatings from the Cr-Hf-Mo-Ta-W-N system: properties and high-temperature stability
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Pavel Souček, Stanislava Debnárová, Šárka Zuzjaková, Shuyao Lin, Matej Fekete, Zsolt Czigány, Katalin Balázsi, Lukáš Vrána, Tatiana Pitoňáková, Ondřej Jašek, Petr Zeman, Nikola Koutná
High- and medium-entropy nitride coatings from the Cr-Hf-Mo-Ta-W-N system were studied using ab initio calculations and experiments to clarify the role of entropy and individual elements in phase stability, microstructure, and high-temperature behaviour. Formation energy calculations indicated that nitrogen vacancies stabilise the cubic (fcc) phase, with hafnium and tantalum acting as strong stabilisers, while tungsten destabilises the lattice. Coatings were deposited by reactive magnetron sputtering at approx. 50C (AT) and approx. 580C (HT). All exhibited columnar fcc structures; high-temperature deposition produced denser coatings, lower nitrogen content, and larger crystallites, resulting in higher hardness and elastic modulus. Thermal stability was tested up to 1200C on Si and oxidation at 1400C on sapphire. AT coatings failed early, while most HT coatings endured. Nitrogen loss less than 10 at.% at 1000C was critical for survival. TEM revealed tungsten segregation and HfO2 formation, while fcc nitride remained dominant. Ta enrichment proved essential for superior thermal and oxidation stability.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Retardance of lab grown diamond substrates as a function of thickness: momentum-drift random walk model
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Thanh Tran, Phuong Vo, Thomas Sheppard, Timothy Grotjohn, Paul Quayle
This work studies the correlation between mean retardance and thickness of diamond substrates grown homoepitaxially via microwave plasma-enhanced chemical vapor deposition (MPCVD). We measure the retardance of a diamond substrate in two orientations: perpendicular and parallel to the growth direction. Our experimental results demonstrate that the correlation between mean retardance and thickness differs for these orientations. When measured perpendicular to the growth direction, the mean retardance is approximately proportional to the square root of the substrate thickness. In contrast, when measured parallel to the growth direction, we observe a generally higher mean retardance and an approximately linear correlation with thickness. This anisotropy arises not from differences in stress magnitude but from differences in the interlayer correlation of the principal stress axes, as evidenced by correlation coefficients between the azimuth angles of consecutive layers in the diamond crystal. To simulate the integrated retardance of diamond wafers, we propose a two-dimensional random walk model with momentum drift, which captures the diamond crystal tendency to preserve the azimuth angle across the samples. By optimizing the momentum factor, we show that the model can closely match experimental data. The momentum factor is found higher along the growth direction, which is consistent with the calculated correlation coefficients. Furthermore, both the model and experiments indicate that retardance-to-thickness ratios of thin samples converge toward similar base retardances in both orientations. These findings establish a quantitative framework for interpreting birefringence in diamond substrates, with implications for material selection and development in thermal management, quantum sensing, high-power electronics, and optical applications.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
20 pages, 8 figures
Autonomous interpretation of atomistic scattering data
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Andy S. Anker, John L. A. Gardner, Louise A. M. Rosset, Andrew L. Goodwin, Volker L. Deringer
Materials with bespoke properties have long been identified by computational searches, and their experimental realisation is now coming within reach through autonomous laboratories. Scattering experiments are central to verifying the atomic structures of autonomously synthesised materials. Yet, interpreting these measurements typically requires user expertise and manual processing, or machine learning (ML) models trained on predefined datasets, limiting fully autonomous materials discovery. Here, we introduce a differentiable optimisation framework that treats scattering calculations, energetics, and chemical constraints as a unified refinement problem. Capability demonstrations across molecules, crystal structures, nanoparticles, and amorphous matter show that this data-driven approach resolves structural degeneracies with multi-modal inputs - suggesting its usefulness for informing, and ultimately guiding, the operation of autonomous laboratories.
Materials Science (cond-mat.mtrl-sci)
Analytic expressions for estimation of the critical properties of inhomogeneous Ising models
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-08 20:00 EDT
Vladislav Egorov (1), Stepan Osipov (2) ((1) Research Center “Kurchatov Institute” - Scientific Research Institute of System Analysis, Moscow, Russian Federation, (2) Cherepovets State University, Cherepovets, Russian Federation)
In many applications of spin models, the fast estimation of their critical temperatures and other physical properties is of great importance. In this work, we present the analytical expressions estimating the critical properties of inhomogeneous Ising models with ferromagnetic interactions. The expressions were obtained within the framework of the m-vicinity method. The accuracy of the critical temperature estimations was evaluated through comparison with Monte Carlo simulations. Special attention was given to the case when the model consists of two interacting interpenetrating homogeneous sublattices, and relationships for the compositional dependence of the critical temperature were derived.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn)
13 pages, 2 figures
Effect of crystallographic texture on dealloying kinetics and composition of nanoporous gold surface
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Ezgi Hatipoğlu, Ayman A. El-Zoka, Yujun Zhao, Stanislav Mráz, Jochen M. Schneider, Baptiste Gault, Aparna Saksena
Nanoporous metals allow for tailoring composition and surface-to-volume ratio, both aspects critical for applications in catalysis. Here, Ag70Au30 (2 at. %) films with a face-centered cubic structure were deposited at 400°C, either {111}-textured or randomly oriented. Upon chemical dealloying, atom probe tomography of the nanoporous structure reveals that the textured film retains a up to 2.7 times higher Ag concentration within the ligaments compared to the randomly oriented film that exhibits ligament coarsening, indicating faster dealloying kinetics. Our study highlights the potential of microstructure engineering in tailoring the properties of nanoporous metals for possible future catalytic and electrochemical applications.
Materials Science (cond-mat.mtrl-sci)
Metastability of the Topological Magnetic Orders in the Chiral Antiferromagnet EuPtSi
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Simon Rousseau, Gabriel Seyfarth, Georg Knebel, Dai Aoki, Yoshichika Ōnuki, Alexandre Pourret
We report resistivity and Hall effect measurements in the chiral antiferromagnet EuPtSi. Depending on the magnetic field orientation with respect to the crystallographic axes, EuPtSi presents different topological magnetic phases below the Néel temperature $ T_N=4.05$ K. In particular, for a field $ H \parallel $ [111], it exhibits the well known skyrmion lattice A-phase inside the conical phase between $ T=0.45$ K and $ T_N$ in the field range from 0.8T to 1.4T. Remarkably, the skyrmion lattice state in EuPtSi, composed of nanoscale skyrmions, can be extended down to very low temperature (lower than 0.1K) through field-cooling regardless of the cooling rate and of the magnetic history. Similarly the metastability of the A’- and B-phases ($ H \parallel $ [100]) at low temperature is evidenced by our measurements. These results suggest that EuPtSi is a peculiar example where the competition between the topological stability and the thermal agitation can lead to metastable quantum skyrmion state.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 8 figures
Commensurate-incommensurate Mott transition without magnetic field: emergence of nematic Luttinger liquid in XXZ chain
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Julien Fitouchi, Natalia Chepiga
We investigate the zero-magnetization phase diagram of a spin-1/2 chain with competing ferromagnetic nearest-neighbor and antiferromagnetic next-nearest-neighbor exchange couplings in the strongly interacting regime. Using density matrix renormalization group (DMRG) simulations, we discover two successive commensurate-incommensurate transitions of the non-conformal Pokrovsky-Talapov universality class, occurring (even) at zero magnetic field. The first transition marks the condensation of bound pairs of magnons into a critical phase with central charge $ c=2$ , emerging from a gapped period-4 phase. At the second transition, an incommensurate quadrupolar (or nematic) Luttinger liquid forms out of a gapped phase separation state, via the pairwise condensation of domain walls. We argue that both transitions involve the same underlying incommensurate nematic Luttinger liquid, and that the $ c=2$ phase can be understood as a coexistence of a conventional (single-magnon type) and quadrupolar (two-magnon type) Luttinger liquids. Our results demonstrate that frustration alone is sufficient to drive continuous commensurate-incommensurate transitions of Mott type and stabilise incommensurate quasi-long-range order without doping.
Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 8 figures
Magnon-Magnon Interaction Induced by Dynamic Coupling in a Hybrid Magnonic Crystal
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Rawnak Sultana, Mojtaba Taghipour Kaffash, Gianluca Gubbiotti, Yi Ji, M. Benjamin Jungfleisch, Federico Montoncello
We report a combined experimental and numerical investigation of spin-wave dynamics in a hybrid magnonic crystal consisting of a CoFeB artificial spin ice (ASI) of stadium-shaped nanoelements patterned atop a continuous NiFe film, separated by a 5 nm Al2O3 spacer. Using Brillouin light scattering spectroscopy, we probe the frequency dependence of thermal spin waves as functions of applied magnetic field and wavevector, revealing the decisive role of interlayer dipolar coupling in the magnetization dynamics. Micromagnetic simulations complement the experiments, showing a strong interplay between ASI edge modes and backward volume modes in the NiFe film. The contrast in saturation magnetization between CoFeB and NiFe enhances this coupling, leading to a pronounced hybridization manifested as a triplet of peaks in the spectra - predicted by simulations and observed experimentally. This magnon-magnon coupling persists over a wide magnetic field range, shaping both the spin-wave dispersion and frequency-field response throughout the hysteresis loop. Our findings establish how ASI geometry can selectively enhance specific spin-wave wavelengths in the underlying film, identifying them as preferential channels for magnonic signal transport and manipulation.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Other Condensed Matter (cond-mat.other)
Spin wave theory for the triaxial magnetic anisotropy 2D van der Waals antiferromagnet CrSBr
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Sergio M. Rezende, Byron Freelon, Roberto L. Rodríguez-Suárez
The magnetic properties of two-dimensional (2D) materials have been attracting increasing attention in recent years due to their unique behavior and possible applications in new devices. One material of great interest is the 2D van der Waals (vdW) crystal CrSBr, that exhibits antiferromagnetic (AF) order at low temperatures due to an interlayer AF exchange interaction. Here we present a full quantum spin-wave theory for CrSBr considering three intralayer and one interlayer exchange interactions, and triaxial magnetic anisotropy. The fits of the theoretical results to antiferromagnetic resonance (AFMR) measurements and inelastic neutron scattering data yield reliable values for the seven interaction parameters that can be used to calculate other properties of this interesting material.
Materials Science (cond-mat.mtrl-sci)
8 pages, 4 figures
Unveiling the entropic role of hydration water in SOD1 partitioning within FUS condensate
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-08 20:00 EDT
Luis Enrique Coronas, Stepan Timr, Fabio Sterpone, Giancarlo Franzese
Biological processes like the sequestration of Superoxide Dismutase 1 (SOD1) into biomolecular condensates such as FUS and stress granules are essential to understanding disease mechanisms, including amyotrophic lateral sclerosis (ALS). Our study demonstrates that the hydration environment is crucial in these processes. Using the advanced CVF water model, which captures hydrogen-bond networks at the molecular level, we show how water greatly impacts SOD1’s behavior, residency times, and transition rates between different associative states. Importantly, when water is included to hydrate an implicit solvent model (OPEP), we gain a new perspective on the free energy landscape of the system, leading to a conclusion that clarifies that suggested by OPEP alone. While the OPEP model indicated that Bovine Serum Albumin (BSA) crowders reduce SOD1’s partition coefficient (PC) mainly due to nonspecific interactions with BSA, our enhanced explicit-water approach reveals that the hydration entropy behavior in BSA drives the observed decrease in PC. This highlights that explicitly modeling water is essential for accurately understanding protein-crowder interactions and their biological relevance, emphasizing water’s role in cellular phase separation and disease-related processes.
Statistical Mechanics (cond-mat.stat-mech)
25 pages, 13 figures, 3 tables. Submitted to The Journal of Chemical Physics
Phase Behavior of Thermo-Responsive Nanoplatelets
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-08 20:00 EDT
Imane Boucenna, Florent Carn, Ahmed Mourchid
Nanoplatelets open up a wide range of possibilities for building materials with novel properties linked to their shape anisotropy. A challenge consists of controlling dynamically the order of positioning and orientation in three dimensions by assembly to exploit the collective properties at the macroscale. While most studies to date have focused on hard platelets that cannot be stimulated by an external trigger, in the present work we tackle the case of core/shell platelets, composed of a mineral core (laponite) coated with a soft polymeric shell (PEO100-PPO65-PEO100 copolymer) whose swelling can be triggered by temperature variation. We identified unambiguously the signature associated with the different phases obtained as a function temperature and concentration by combining local (X-ray scattering, electron microscopy) and global (rheology, optical birefringence) methods of analysis. In this way, we obtained two main results. The first shows that the deposition of a soft layer onto laponite surface enables a phase transition from isotropic liquid towards liquid suspensions of random stacks which is not observed for bare laponite suspensions in the studied weight concentration range (\Phi < 14 wt.). The second result shows that an increase of nanoplatelet effective volume fraction triggered by temperature (swelling of the polymer shell) induces a phase transition from liquid suspensions of random stacks towards birefringent gels of nematic stacks. Both results agree with numerically predicted phase sequences expected by variation in particle density under similar charge screening conditions, taking into account the contribution of the copolymer layer to the particle volume fraction. We believe that these results pave the way for the control of nanoplatelet self-assembly by external action.
Soft Condensed Matter (cond-mat.soft)
Langmuir 2025
Colorimetry and Tribology of Ultrapure Copper Surface Micromodification
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Aleksandra Szczupak, Grzegorz Cios, Benedykt R. Jany
Controlling optical and tribological properties of metal surfaces, like color and wear rate, without altering their chemical composition is a highly desirable process across numerous fields of science and industry. It represents a cost-effective alternative to traditional chemical methods, particularly for copper, one of the most important metals widely used where high electrical and thermal conductivity, alongside resistance to corrosion, are required. We investigated the control of copper surface texture through a controlled micromodification process, utilizing constant force and velocity with abrasive silicon carbide sandpaper on ultrapure copper pellets exhibiting elongated crystallographic grains, and its impact on optical properties. Systematically varying grit size and rubbing direction, both along and across the grains, resulted in tunable microgroove morphology, demonstrating a marked difference in wear rate between single-grain and multi-grain abrasion. Furthermore, modification along copper grain boundaries yielded a change in the wear rate by a factor of two, related to single-grain and multi-grain abrasion regime changes, enabling precise control over material performance via tuned abrasion conditions. Colorimetric analysis via C-Microscopy revealed a strong, statistically significant relationship between abrasive parameters, microgroove geometry (inclination angle, depth, and size), and optical spectral signatures, which were then parametrized to achieve targeted control. This research demonstrates a simple yet effective approach to color and reflectance modification via microgroove engineering, offering a pathway to customized material properties by uniquely coupling contact mechanics, surface morphology, and colorimetry at the microscale level.
Materials Science (cond-mat.mtrl-sci), Optics (physics.optics)
Identifying chiral topological order in microscopic spin models by modular commutator
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Avijit Maity, Aman Kumar, Vikram Tripathi
The chiral central charge $ c_-$ is a key topological invariant of the edge characterizing the bulk two-dimensional chiral topological order, but its direct evaluation in microscopic spin models has long been a challenge, especially for non-abelian topological order. Building on the recently developed modular commutator formalism, we numerically obtain $ c_-$ directly from single ground-state wave functions of two-dimensional interacting spin models that have chiral topological order. This provides a geometry-independent and bulk diagnostic of chirality. We study two nonintegrable systems – the Zeeman-Kitaev honeycomb model and the kagome antiferromagnet – both subjected to scalar spin chirality perturbations. We find that the modular commutator yields results consistent with the expected topological quantum field theories. We also compute the topological entanglement entropy which provides an independent diagnostic of the topological orders. Our work establishes modular commutators as a powerful numerical probe of chiral topological order in strongly correlated quantum magnets.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
6 pages, 4 figures, 2 figures in Supplementary Material
Encoding a topological gauge theory on a ring-shaped Raman-coupled Bose gas
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-08 20:00 EDT
Claudio Iacovelli, Josep Cabedo, Leticia Tarruell, Alessio Celi
Topological gauge theories constitute a framework for understanding strongly correlated quantum matter in terms of weakly interacting composite degrees of freedom. Their topological properties become evident when these theories are realized on a space of non-trivial topology. Here, we propose a scheme to realize a one-dimensional topological gauge theory, the chiral BF theory, on a ring geometry. We obtain such a theory by dimensionally reducing Chern-Simons theory on a disk to the so-called chiral BF theory defined on the ring. Then, we encode the theory into a Hamiltonian with a coupling between angular momentum and density, and we propose and numerically benchmark its realization in an optically-dressed Bose gas confined in a ring-shaped trap. There, the topological properties of the underlying theory manifest themselves through a magnetic flux variable that is density-dependent. We quantify such density-dependent magnetic flux in terms of the ground-state angular momentum and the chiral properties of the system through a Bogoliubov analysis. Our proposal enables the observation of the interplay between the topology of the theory and that of the space.
Quantum Gases (cond-mat.quant-gas)
11 pages + appendix, 3 figures
Phase-induced switching of ferromagnetic insulators in Josephson spin valves
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-08 20:00 EDT
A. A. Mazanik, C.-H. Huang, Miguel A. Cazalilla, F. S. Bergeret
We study the Josephson effect in junctions composed of two ferromagnetic insulator/diffusive superconductor bilayers separated by an insulating barrier. By computing the free energy of the system, we identify two distinct contributions: (i) The work performed by a current source to create a supercurrent through the junction, and (ii) an antiferromagnetic coupling between ferromagnetic insulators, mediated by the superconducting condensate across the insulating barrier. The competition between these contributions allows for switching between parallel and antiparallel configurations of the magnetizations of the ferromagnetic insulators. We explicitly show that the switching occurs at finite temperatures and for superconducting phase differences satisfying $ \pi/2 < \phi < 3\pi/2$ . Importantly, this effect can be realized in ferromagnetic insulators with sufficiently large easy-plane anisotropy energy. Using realistic junction parameters, we demonstrate that the switching can be controlled by phase bias and triggered by half-flux-quantum voltage pulses or external magnetic field pulses on the microsecond timescale. These results provide a route towards controllable Josephson-based superconducting memory devices based on EuS/Al heterostructures.
Superconductivity (cond-mat.supr-con)
7 pages, 4 figures
Origin of trapped intralayer Wannier and charge-transfer excitons in moiré materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Indrajit Maity, Johannes Lischner, Arash A. Mostofi, Ángel Rubio
Moiré materials offer a versatile platform for engineering excitons with unprecedented control, promising next-generation optoelectronic applications. While continuum models are widely used to study moiré excitons due to their computational efficiency, they often disagree with ab initio many-body approaches, as seen for intralayer excitons in WS$ _2$ /WSe$ _2$ heterobilayers. Here, we resolve these discrepancies using an atomistic, quantum-mechanical framework based on the Bethe-Salpeter equation with localized Wannier functions as the basis for the electronic structure. We show that inclusion of dielectric screening due to hexagonal boron nitride (hBN) encapsulation is essential to reproduce the full set of experimentally observed features of moiré intralayer excitons. Our analysis reveals a competition between Wannier and charge transfer characters, driven by variations between direct and indirect band gaps at high symmetry stacking regions due to atomic relaxations and environmentally tunable electron-hole interactions. Building on this insight, we demonstrate that the lowest-energy bright excitons are Wannier-like in WS2/WSe2 heterobilayers but charge-transfer-like in twisted WSe2 homobilayers, despite having comparable moiré lengths when encapsulated in hBN. In the absence of hBN encapsulation, the lowest-energy bright exciton in twisted WSe$ _2$ becomes Wannier-like. These results establish atomistic modeling as a powerful and efficient approach for designing and controlling excitonic phenomena in moiré materials.
Materials Science (cond-mat.mtrl-sci)
Hydrodynamic Mechanism of Colloidal Propulsion through Momentum Exchange
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-08 20:00 EDT
Javier Diaz, Ignacio Pagonabarraga, Carles Calero
Propulsion of colloidal particles due to momentum transfer from localized surface reactions is investigated by solving the exact unsteady Stokes equation. We model the effect of surface reactions as either a {\it force dipole} acting on the fluid or a {\it pair force} acting on both the colloid and the fluid. Our analysis reveals that after a single reaction event the colloid’s velocity initially decays as $ \sim t^{-1/2}$ , followed by a long-time tail decay $ \sim t^{-5/2}$ . This behavior is distinct from the $ \sim t^{-3/2}$ decay seen for simple impulsively forced particles, a result of the force-free nature of the reaction mechanism. The velocity and transient dynamics are strongly controlled by the distance of the reaction from the colloid surface. For a colloid subject to periodic reactions, the theory predicts a steady-state velocity that is comparable to experimental results and previous simulations, suggesting that direct momentum transfer is a relevant mechanism for self-propulsion in systems like Janus particles. Finally, our study shows that fluid compressibility is not required for momentum transfer to produce colloidal propulsion.
Soft Condensed Matter (cond-mat.soft)
Bridging the Synthesizability Gap in Perovskites by Combining Computations, Literature Data, and PU Learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-08 20:00 EDT
Rushik Desai, Junyeong Ahn, Alejandro Strachan, Arun Mannodi-Kanakkithodi
Among emerging energy materials, halide and chalcogenide perovskites have garnered significant attention over the last decade owing to the abundance of their constituent species, low manufacturing costs, and their highly tunable composition-structure-property space. Navigating the vast perovskite compositional landscape is possible using density functional theory (DFT) computations, but they are not easily extended to predictions of the synthesizability of new materials and their properties. As a result, only a limited number of compositions identified to have desirable optoelectronic properties from these calculations have been realized experimentally. One way to bridge this gap is by learning from the experimental literature about how the perovskite composition-structure space relates to their likelihood of laboratory synthesis. Here, we present our efforts in combining high-throughput DFT data with experimental labels collected from the literature to train classifier models employing various materials descriptors to forecast the synthesizability of any given perovskite compound. Our framework utilizes the positive and unlabeled (PU) learning strategy and makes probabilistic estimates of the synthesis likelihood based on DFT- computed energies and the prior existence of similar synthesized compounds. Our data and models can be readily accessed via a Findable, Accessible, Interoperable, and Reproducible (FAIR) nanoHUB tool.
Materials Science (cond-mat.mtrl-sci)
Frieze charge-stripes in a correlated kagome superconductor CsCr$_3$Sb$_5$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-08 20:00 EDT
Siyu Cheng, Keyu Zeng, Yi Liu, Christopher Candelora, Ziqiang Wang, Guang-Han Cao, Ilija Zeljkovic
Kagome metals have developed into a vibrant playground for materials physics, where geometric frustration, electronic correlations and band topology come together to create a variety of exotic phenomena. Recently synthesized CsCr$ _3$ Sb$ _5$ has provided a rare opportunity to explore unconventional superconductivity in a strongly correlated kagome system with hints of frustrated magnetism and quantum criticality. Using spectroscopic imaging scanning tunneling microscopy, we reveal a cascade of density wave transitions with different symmetries in bulk single crystals of CsCr$ _3$ Sb$ _5$ . In particular, we discover a new electronic state $ -$ a unidirectional density wave that breaks all mirror symmetries akin to a chiral density wave, but in contrast retains a mirror-glide symmetry. We term this state a frieze charge-stripe order phase, because its symmetry properties agree with one of the fundamental frieze symmetry groups. A combination of high-resolution imaging, Fourier analysis and theoretical simulations uncovers the crucial role of sublattice degrees of freedom in forming this phase, with internal chiral textures of opposite handedness. Our experiments reveal that superconductivity in CsCr$ _3$ Sb$ _5$ develops from a new type of a unidirectional density wave, and set the foundation for exploring electronic states with frieze symmetry groups in quantum materials.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)