CMP Journal 2025-10-01
Statistics
Nature: 19
Nature Materials: 2
Nature Nanotechnology: 1
Physical Review Letters: 22
Physical Review X: 1
arXiv: 76
Nature
Proteotoxic stress response drives T cell exhaustion and immune evasion
Original Paper | Lymphocytes | 2025-09-30 20:00 EDT
Yi Wang, Anjun Ma, No-Joon Song, Ariana E. Shannon, Yaa S. Amankwah, Xingyu Chen, Weidong Wu, Ziyu Wang, Abbey A. Saadey, Amir Yousif, Gautam Ghosh, Jay K. Mandula, Maria Velegraki, Tong Xiao, Haitao Wen, Stanley Ching-Cheng Huang, Ruoning Wang, Christian M. Beusch, Abdelhameed S. Dawood, David E. Gordon, Mohamed S. Abdel-Hakeem, Hazem E. Ghoneim, Gang Xin, Brian C. Searle, Zihai Li
Chronic infections and cancer cause T cell dysfunction known as exhaustion. This cell state is caused by persistent antigen exposure, suboptimal co-stimulation and a plethora of hostile factors that dampen protective immunity and limit the efficacy of immunotherapies1,2,3,4. The mechanisms that underlie T cell exhaustion remain poorly understood. Here we analyse the proteome of CD8+ exhausted T (Tex) cells across multiple states of exhaustion in the context of both chronic viral infections and cancer. We show that there is a non-stochastic pathway-specific discordance between mRNA and protein dynamics between T effector (Teff) and Tex cells. We identify a distinct proteotoxic stress response (PSR) in Tex cells, which we term Tex-PSR. Contrary to canonical stress responses that induce a reduction in protein synthesis5,6, Tex-PSR involves an increase in global translation activity and an upregulation of specialized chaperone proteins. Tex-PSR is further characterized by the accumulation of protein aggregates and stress granules and an increase in autophagy-dominant protein catabolism. We establish that disruption of proteostasis alone can convert Teff cells to Tex cells, and we link Tex-PSR mechanistically to persistent AKT signalling. Finally, disruption of Tex-PSR-associated chaperones in CD8+ T cells improves cancer immunotherapy in preclinical models. Moreover, a high Tex-PSR in T cells from patients with cancer confers poor responses to clinical immunotherapy. Collectively, our findings indicate that Tex-PSR is a hallmark and a mechanistic driver of T cell exhaustion, which raises the possibility of targeting proteostasis pathways as an approach for cancer immunotherapy.
Lymphocytes, Tumour immunology
Kirigami-inspired parachutes with programmable reconfiguration
Original Paper | Aerospace engineering | 2025-09-30 20:00 EDT
Danick Lamoureux, Jérémi Fillion, Sophie Ramananarivo, Frédérick P. Gosselin, David Melancon
The art of kirigami allows programming a sheet to deform into a particular manner with a pattern of cuts, endowing it with exotic mechanical properties and behaviours1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17. Here we program discs to deform into stably falling parachutes as they deploy under fluid-structure interaction. Parachutes are expensive and delicate to manufacture, which limits their use for humanitarian airdrops or drone delivery. Laser cutting a closed-loop kirigami pattern18 in a disc induces porosity and flexibility into an easily fabricated parachute. By performing wind tunnel testing and numerical simulations using a custom flow-induced reconfiguration model19, we develop a design tool to realize kirigami-inspired parachutes. Guided by these results, we fabricate parachutes from the centimetre to the metre scale and test them in realistic conditions. We show that at low load-to-area ratios, kirigami-inspired parachutes exhibit a comparable terminal velocity to conventional ones. However, unlike conventional parachutes that require a gliding angle for vertical stability20 and fall at random far from a target, our kirigami-inspired parachutes always fall near the target, regardless of their initial release angle. These kinds of parachutes could limit material losses during airdropping as well as decrease manufacturing costs and complexity.
Aerospace engineering, Fluid dynamics, Mechanical engineering
Efferocytic remodelling of pancreatic islet macrophages by limited β-cell death
Original Paper | Autoimmunity | 2025-09-30 20:00 EDT
Pavel N. Zakharov, Chanchal S. Chowdhury, Orion J. Peterson, Brady Barron, Anthony N. Vomund, Laurent Gorvel, Emil R. Unanue, Eynav Klechevsky, Xiaoxiao Wan, Kodi S. Ravichandran
The primary driver of type I diabetes is the autoimmune T cells that destroy insulin-producing β-cells within the islets of Langerhans in the pancreas1. Pancreatic islet macrophages have also been variably linked to disease onset and progression. As macrophage-mediated removal of dying cells through efferocytosis regulates tissue homeostasis and immune responses2, here we investigated how efferocytosis by intra-islet macrophages influences the immune environment of pancreatic islets. Using a series of complementary omics-based and functional approaches, we identify a subset of anti-inflammatory intra-islet efferocytic macrophages (e-Mac) within the pancreas of mice and humans. When limited β-cell apoptosis is induced in vivo in wild-type C57BL/6 mice and diabetic-prone NOD mice, islet macrophages adopt this e-Mac phenotype without an apparent increase in the total numbers of intra-islet macrophages. Such limited β-cell apoptosis and increase in e-Mac numbers led to long-term suppression of autoimmune diabetes in NOD mice. This e-Mac phenotype could also be recapitulated ex vivo by co-culturing macrophages with apoptotic β-cells. Mechanistically, the e-Mac-enriched populations imparted an anergic-like state on CD4+ T cells ex vivo and promoted accumulation of such anergic-like CD4+ T cells in vivo within the islets. Analysing macrophage-T cell interactions within pancreatic islets using NicheNet and targeted experimental validation, we identify the IGF-1-IGF1R axis as a contributor to the anergic-like T cell phenotype in the islets. Collectively, these data advance a concept that efferocytosis-associated reprogramming of the islet macrophages and the subsequent influence on the adaptive immune response could be beneficial in modulating diabetic autoimmunity.
Autoimmunity, Monocytes and macrophages
Dietary cysteine enhances intestinal stemness via CD8+ T cell-derived IL-22
Original Paper | Intestinal stem cells | 2025-09-30 20:00 EDT
Fangtao Chi, Qiming Zhang, Jessica E. S. Shay, Shixun Han, Johanna Ten Hoeve, Yin Yuan, Zhenning Yang, Heaji Shin, Samuel Block, Sumeet Solanki, Yatrik M. Shah, Matthew G. Vander Heiden, Judith Agudo, Ömer H. Yilmaz
A fundamental question in physiology is understanding how tissues adapt and alter their cellular composition in response to dietary cues1,2,3,4,5,6,7,8. The mammalian small intestine is maintained by rapidly renewing LGR5+ intestinal stem cells (ISCs) that respond to macronutrient changes such as fasting regimens and obesogenic diets, yet how specific amino acids control ISC function during homeostasis and injury remains unclear. Here we demonstrate that dietary cysteine, a semi-essential amino acid, enhances ISC-mediated intestinal regeneration following injury. Cysteine contributes to coenzyme A (CoA) biosynthesis in intestinal epithelial cells, which promotes expansion of intraepithelial CD8αβ+ T cells and their production of interleukin-22 (IL-22). This enhanced IL-22 signalling directly augments ISC reparative capacity after injury. The mechanistic involvement of the pathway in driving the effects of cysteine is demonstrated by several findings: CoA supplementation recapitulates cysteine effects, epithelial-specific loss of the cystine transporter SLC7A11 blocks the response, and mice with CD8αβ+ T cells lacking IL-22 or a depletion of CD8αβ+ T cells fail to show enhanced regeneration despite cysteine treatment. These findings highlight how coupled cysteine metabolism between ISCs and CD8+ T cells augments intestinal stemness, providing a dietary approach that exploits ISC and immune cell crosstalk for ameliorating intestinal damage.
Intestinal stem cells, Metabolomics
A new paradigm for outer membrane protein biogenesis in the Bacteroidota
Original Paper | Bacterial secretion | 2025-09-30 20:00 EDT
Xiaolong Liu, Luis Orenday Tapia, Justin C. Deme, Susan M. Lea, Ben C. Berks
In Gram-negative bacteria, the outer membrane is the first line of defence against antimicrobial agents and immunological attacks1. A key part of outer membrane biogenesis is the insertion of outer membrane proteins by the β-barrel-assembly machinery (BAM)2,3,4. Here we report the cryo-electron microscopy structure of a BAM complex isolated from Flavobacterium johnsoniae, a member of the Bacteroidota, a phylum that includes key human commensals and major anaerobic pathogens. This BAM complex is extensively modified from the canonical Escherichia coli system and includes an extracellular canopy that overhangs the substrate folding site and a subunit that inserts into the BAM pore. The novel BamG and BamH subunits that are involved in forming the extracellular canopy are required for BAM function and are conserved across the Bacteroidota, suggesting that they form an essential extension to the canonical BAM core in this phylum. For BamH, isolation of a suppressor mutation enables the separation of its essential and non-essential functions. The need for a highly remodelled and enhanced BAM complex reflects the unusually complex membrane proteins found in the outer membrane of the Bacteroidota.
Bacterial secretion, Cryoelectron microscopy
Signal amplification in a solid-state sensor through asymmetric many-body echo
Original Paper | Quantum information | 2025-09-30 20:00 EDT
Haoyang Gao, Leigh S. Martin, Lillian B. Hughes, Nathaniel T. Leitao, Piotr Put, Hengyun Zhou, Nazli U. Koyluoglu, Simon A. Meynell, Ania C. Bleszynski Jayich, Hongkun Park, Mikhail D. Lukin
Electronic spins of nitrogen-vacancy centres in diamond constitute a promising system for micro- and nanoscale magnetic sensing1,2,3,4, because of their operation under ambient conditions5, ease of placement in close proximity to sensing targets6 and biological compatibility7. At high densities, the electronic spins interact through dipolar coupling, which typically limits8 but can also potentially enhance9 sensing performance. Here we report the experimental demonstration of many-body signal amplification in a solid-state, room-temperature quantum sensor. Our approach uses time-reversed two-axis-twisting interactions, engineered through dynamical control of the quantization axis and Floquet engineering10 in a two-dimensional ensemble of nitrogen-vacancy centres. We observe that optimal amplification occurs when the backward evolution time equals twice the forward evolution time, in sharp contrast to the conventional Loschmidt echo11,12. These observations can be understood as resulting from an underlying time-reversed mirror symmetry of the microscopic dynamics, providing key insights into signal amplification and opportunities for practical entanglement-enhanced quantum sensing.
Quantum information, Quantum metrology
Heat-rechargeable computation in DNA logic circuits and neural networks
Original Paper | DNA computing | 2025-09-30 20:00 EDT
Tianqi Song, Lulu Qian
Metabolism enables life to sustain dynamics and to repeatedly interact with the environment by storing and consuming chemical energy. A major challenge for artificial molecular machines is to find a universal energy source akin to ATP for biological organisms and electricity for electromechanical machines. More than 20 years ago, DNA was first used as fuel to drive nanomechanical devices1,2 and catalytic reactions3. However, each system requires distinct fuel sequences, preventing DNA alone from becoming a universal energy source. Despite extensive efforts4, we still lack an ATP-like or electricity-like power supply to sustain diverse molecular machines. Here we show that heat can restore enzyme-free DNA circuits from equilibrium to out-of-equilibrium states. During heating and cooling, nucleic acids with strong secondary structures reach kinetically trapped states5,6, providing energy for subsequent computation. We demonstrate that complex logic circuits and neural networks, involving more than 200 distinct molecular species, can respond to a temperature ramp and recharge within minutes, allowing at least 16 rounds of computation with varying sequential inputs. Our strategy enables diverse systems to be powered by the same energy source without problematic waste build-up, thereby ensuring consistent performance over time. This scalable approach supports the sustained operation of enzyme-free molecular circuits and opens opportunities for advanced autonomous behaviours, such as iterative computation and unsupervised learning in artificial chemical systems.
DNA computing, Thermodynamics
Monoclonal antibodies protect against pandrug-resistant Klebsiella pneumoniae
Original Paper | Antimicrobial responses | 2025-09-30 20:00 EDT
Emanuele Roscioli, Vittoria Zucconi Galli Fonseca, Soraya Soledad Bosch, Ida Paciello, Giuseppe Maccari, Giulia Cardinali, Giampiero Batani, Samuele Stazzoni, Giusy Tiseo, Cesira Giordano, Shen Yuwei, Laura Capoccia, Dario Cardamone, Matteo Ridelfi, Marco Troisi, Noemi Manganaro, Chiara Mugnaini, Concetta De Santi, Annalisa Ciabattini, Linda Cerofolini, Marco Fragai, Danilo Licastro, Kelly Wyres, Laurent Dortet, Simona Barnini, David P. Nicolau, Francesco Menichetti, Marco Falcone, Kamilia Abdelraouf, Claudia Sala, Anna Kabanova, Rino Rappuoli
The ‘silent pandemic’ caused by antimicrobial resistance requires innovative therapeutic approaches. Human monoclonal antibodies (mAbs), which are among the most transformative and safe drugs in oncology1 and autoimmunity2, are rarely used for infectious diseases and not yet used for antimicrobial resistance3. Here we applied an antigen-agnostic strategy to isolate extremely potent human mAbs against Klebsiella pneumoniae sequence type 147 (ST147), a hypervirulent and pandrug-resistant lineage that is spreading globally. Isolated mAbs target the KL64 capsule and the O-antigen. However, although mAbs displayed bactericidal activity in the picomolar range in vitro, only the capsule-specific mAbs were protective against fulminant bloodstream infection by ST147 and two geographically and genetically distant carbapenem-resistant KL64-bearing K. pneumoniae. Protection observed in vivo correlated with in vitro bacterial uptake by macrophages and enchained bacterial growth. Our study thus describes a mAb that protects against pandrug-resistant K. pneumoniae and provides a strategy to isolate mAbs and identify mAbs that confer protection against bacteria with antimicrobial resistance.
Antimicrobial responses, Bacterial infection, Pathogens
Polygenic and developmental profiles of autism differ by age at diagnosis
Original Paper | Autism spectrum disorders | 2025-09-30 20:00 EDT
Xinhe Zhang, Jakob Grove, Yuanjun Gu, Cornelia K. Buus, Lea K. Nielsen, Sharon A. S. Neufeld, Mahmoud Koko, Daniel S. Malawsky, Emma M. Wade, Ellen Verhoef, Anna Gui, Laura Hegemann, Carrie Allison, Alex Tsompanidis, Deep Adhya, Rosemary Holt, Omar Al-Rubaie, Ramin Ali Marandi Ghoddousi, Alexander E. P. Heazell, Jonathan Mill, Alice Franklin, Rosie Bamford, Matthew E. Hurles, Mahmoud Mousa, David H. Rowitch, Kathy K. Niakan, Graham J. Burton, Tereza Cindrova-Davies, Deepak P. Srivastava, Lucia Dutan-Polit, Adam Pavlinek, Laura Sichlinger, Roland Nagy, Madeline A. Lancaster, Jose Gonzalez-Martinez, Tal Biron-Shental, Lidia V. Gabis, Dorothea Floris, Richard Bethlehem, Michael V. Lombardo, Marcin Radecki, Meng-Chuan Lai, Yeshaya David Greenberg, Elizabeth Weir, Florina Uzefovsky, Yumnah T. Khan, Juan Pablo Del Rio, Jonas Bybjerg-Grauholm, David M. Hougaard, Ole Mors, Preben Bo Mortensen, Merete Nordentoft, Thomas Werge, Caroline M. Nievergelt, Adam X. Maihofer, Elizabeth G. Atkinson, Chia-Yen Chen, Karmel W. Choi, Jonathan R. I. Coleman, Nikolaos P. Daskalakis, Laramie E. Duncan, Renato Polimanti, Cindy Aaronson, Ananda B. Amstadter, Soren B. Andersen, Ole A. Andreassen, Paul A. Arbisi, Allison E. Ashley-Koch, S. Bryn Austin, Esmina Avdibegoviç, Dragan Babić, Silviu-Alin Bacanu, Dewleen G. Baker, Anthony Batzler, Jean C. Beckham, Sintia Belangero, Corina Benjet, Carisa Bergner, Linda M. Bierer, Joanna M. Biernacka, Laura J. Bierut, Jonathan I. Bisson, Marco P. Boks, Elizabeth A. Bolger, Amber Brandolino, Gerome Breen, Rodrigo Affonseca Bressan, Richard A. Bryant, Angela C. Bustamante, Jonas Bybjerg-Grauholm, Marie Bækvad-Hansen, Sigrid Børte, Leah Cahn, Joseph R. Calabrese, Jose Miguel Caldas-de-Almeida, Chris Chatzinakos, Sheraz Cheema, Sean A. P. Clouston, Lucía Colodro-Conde, Brandon J. Coombes, Carlos S. Cruz-Fuentes, Anders M. Dale, Shareefa Dalvie, Lea K. Davis, Jürgen Deckert, Douglas L. Delahanty, Michelle F. Dennis, Frank Desarnaud, Christopher P. DiPietro, Seth G. Disner, Anna R. Docherty, Katharina Domschke, Grete Dyb, Alma Džubur Kulenović, Howard J. Edenberg, Alexandra Evans, Chiara Fabbri, Negar Fani, Lindsay A. Farrer, Adriana Feder, Norah C. Feeny, Janine D. Flory, David Forbes, Carol E. Franz, Sandro Galea, Melanie E. Garrett, Bizu Gelaye, Joel Gelernter, Elbert Geuze, Charles F. Gillespie, Slavina B. Goleva, Scott D. Gordon, Aferdita Goçi, Lana Ruvolo Grasser, Camila Guindalini, Magali Haas, Saskia Hagenaars, Michael A. Hauser, Andrew C. Heath, Sian M. J. Hemmings, Victor Hesselbrock, Ian B. Hickie, Kelleigh Hogan, David Michael Hougaard, Hailiang Huang, Laura M. Huckins, Kristian Hveem, Miro Jakovljević, Arash Javanbakht, Gregory D. Jenkins, Jessica Johnson, Ian Jones, Tanja Jovanovic, Karen-Inge Karstoft, Milissa L. Kaufman, James L. Kennedy, Ronald C. Kessler, Alaptagin Khan, Nathan A. Kimbrel, Anthony P. King, Nastassja Koen, Roman Kotov, Henry R. Kranzler, Kristi Krebs, William S. Kremen, Pei-Fen Kuan, Bruce R. Lawford, Lauren A. M. Lebois, Kelli Lehto, Daniel F. Levey, Catrin Lewis, Israel Liberzon, Sarah D. Linnstaedt, Mark W. Logue, Adriana Lori, Yi Lu, Benjamin J. Luft, Michelle K. Lupton, Jurjen J. Luykx, Iouri Makotkine, Jessica L. Maples-Keller, Shelby Marchese, Charles Marmar, Nicholas G. Martin, Gabriela A. Martínez-Levy, Kerrie McAloney, Alexander McFarlane, Katie A. McLaughlin, Samuel A. McLean, Sarah E. Medland, Divya Mehta, Jacquelyn Meyers, Vasiliki Michopoulos, Elizabeth A. Mikita, Lili Milani, William Milberg, Mark W. Miller, Rajendra A. Morey, Charles Phillip Morris, Ole Mors, Mary S. Mufford, Elliot C. Nelson, Sonya B. Norman, Nicole R. Nugent, Meaghan O’Donnell, Holly K. Orcutt, Pedro M. Pan, Matthew S. Panizzon, Gita A. Pathak, Edward S. Peters, Alan L. Peterson, Matthew Peverill, Robert H. Pietrzak, Melissa A. Polusny, Bernice Porjesz, Abigail Powers, Xue-Jun Qin, Andrew Ratanatharathorn, Victoria B. Risbrough, Andrea L. Roberts, Alex O. Rothbaum, Barbara O. Rothbaum, Peter Roy-Byrne, Kenneth J. Ruggiero, Ariane Rung, Heiko Runz, Bart P. F. Rutten, Stacey Saenz de Viteri, Giovanni Abrahão Salum, Laura Sampson, Sixto E. Sanchez, Marcos Santoro, Carina Seah, Soraya Seedat, Julia S. Seng, Andrey Shabalin, Christina M. Sheerin, Derrick Silove, Alicia K. Smith, Jordan W. Smoller, Scott R. Sponheim, Dan J. Stein, Synne Stensland, Jennifer S. Stevens, Jennifer A. Sumner, Martin H. Teicher, Wesley K. Thompson, Arun K. Tiwari, Edward Trapido, Monica Uddin, Robert J. Ursano, Unnur Valdimarsdóttir, Miranda Van Hooff, Eric Vermetten, Christiaan H. Vinkers, Joanne Voisey, Yunpeng Wang, Zhewu Wang, Monika Waszczuk, Heike Weber, Frank R. Wendt, Michelle A. Williams, Douglas E. Williamson, Bendik S. Winsvold, Sherry Winternitz, Christiane Wolf, Erika J. Wolf, Yan Xia, Ying Xiong, Rachel Yehuda, Keith A. Young, Ross McD. Young, Clement C. Zai, Gwyneth C. Zai, Mark Zervas, Hongyu Zhao, Lori A. Zoellner, John-Anker Zwart, Terri deRoon-Cassini, Sanne J. H. van Rooij, Leigh L. van den Heuvel, Murray B. Stein, Kerry J. Ressler, Karestan C. Koenen, Daniel H. Geschwind, Naomi R. Wray, Alexandra Havdahl, Angelica Ronald, Beate St Pourcain, Elise B. Robinson, Thomas Bourgeron, Simon Baron-Cohen, Anders D. Børglum, Hilary C. Martin, Varun Warrier
Although autism has historically been conceptualized as a condition that emerges in early childhood1,2, many autistic people are diagnosed later in life3,4,5. It is unknown whether earlier- and later-diagnosed autism have different developmental trajectories and genetic profiles. Using longitudinal data from four independent birth cohorts, we demonstrate that two different socioemotional and behavioural trajectories are associated with age at diagnosis. In independent cohorts of autistic individuals, common genetic variants account for approximately 11% of the variance in age at autism diagnosis, similar to the contribution of individual sociodemographic and clinical factors, which typically explain less than 15% of this variance. We further demonstrate that the polygenic architecture of autism can be broken down into two modestly genetically correlated (rg = 0.38, s.e. = 0.07) autism polygenic factors. One of these factors is associated with earlier autism diagnosis and lower social and communication abilities in early childhood, but is only moderately genetically correlated with attention deficit-hyperactivity disorder (ADHD) and mental-health conditions. Conversely, the second factor is associated with later autism diagnosis and increased socioemotional and behavioural difficulties in adolescence, and has moderate to high positive genetic correlations with ADHD and mental-health conditions. These findings indicate that earlier- and later-diagnosed autism have different developmental trajectories and genetic profiles. Our findings have important implications for how we conceptualize autism and provide a model to explain some of the diversity found in autism.
Autism spectrum disorders, Genome-wide association studies
Tracking clonal evolution during treatment in ovarian cancer using cell-free DNA
Original Paper | Cancer genomics | 2025-09-30 20:00 EDT
Marc J. Williams, Ignacio Vázquez-García, Grittney Tam, Michelle Wu, Nancy Varice, Eliyahu Havasov, Hongyu Shi, Duaa H. Al-Rawi, Gryte Satas, Hannah J. Lees, Jake June-Koo Lee, Matthew A. Myers, Matthew Zatzman, Nicole Rusk, Emily Ali, Ronak H. Shah, Michael F. Berger, Neeman Mohibullah, Yulia Lakhman, Dennis S. Chi, Nadeem R. Abu-Rustum, Carol Aghajanian, Andrew McPherson, Dmitriy Zamarin, Brian Loomis, Britta Weigelt, Claire F. Friedman, Sohrab P. Shah
Emergence of drug resistance is the main cause of therapeutic failure in patients with high-grade serous ovarian cancer (HGSOC)1. To study drug resistance in patients, we developed CloneSeq-SV, which combines single-cell whole-genome sequencing2 with targeted deep sequencing of clone-specific genomic structural variants in time-series cell-free DNA. CloneSeq-SV exploits tumour clone-specific structural variants as highly sensitive endogenous cell-free DNA markers, enabling the relative abundance measurements and evolutionary analysis of co-existing clonal populations over the therapeutic time course. Here, using this approach, we studied 18 patients with HGSOC over a multi-year period from diagnosis to recurrence and showed that drug resistance typically arose from selective expansion of a single or small subset of clones present at diagnosis. Drug-resistant clones frequently showed interpretable and distinctive genomic features, including chromothripsis, whole-genome doubling, and high-level amplifications of oncogenes such as CCNE1, RAB25, MYC and NOTCH3. Phenotypic analysis of matched single-cell RNA sequencing data3 indicated pre-existing and clone-specific transcriptional states such as upregulation of epithelial-to-mesenchymal transition and VEGF pathways, linked to drug resistance. In one notable case, clone-specific ERBB2 amplification affected the efficacy of a secondary targeted therapy with a positive patient outcome. Together, our findings indicate that drug-resistant states in HGSOC pre-exist at diagnosis, leading to positive selection and reduced clonal complexity at relapse. We suggest these findings motivate investigation of evolution-informed adaptive treatment regimens to ablate drug resistance in future HGSOC studies.
Cancer genomics, Cancer therapy, Ovarian cancer, Tumour heterogeneity
Connecting chemical and protein sequence space to predict biocatalytic reactions
Original Paper | Biocatalysis | 2025-09-30 20:00 EDT
Alexandra E. Paton, Daniil A. Boiko, Jonathan C. Perkins, Nicholas I. Cemalovic, Thiago Reschützegger, Gabe Gomes, Alison R. H. Narayan
The application of biocatalysis in synthesis has the potential to offer streamlined routes towards target molecules1, tunable catalyst-controlled selectivity2, as well as processes with improved sustainability3. Despite these advantages, biocatalysis is often a high-risk strategy to implement, as identifying an enzyme capable of performing chemistry on a specific intermediate required for a synthesis can be a roadblock that requires extensive screening of enzymes and protein engineering to overcome4. Strategies for predicting which enzyme and small molecule are compatible have been hindered by the lack of well-studied biocatalytic reaction datasets5. The underexploration of connections between chemical and protein sequence space constrains navigation between these two landscapes. Here we report a two-phase effort relying on high-throughput experimentation to populate connections between productive substrate and enzyme pairs and the subsequent development of a tool, CATNIP, for predicting compatible α-ketoglutarate (α-KG)/Fe(ii)-dependent enzymes for a given substrate or, conversely, for ranking potential substrates for a given α-KG/Fe(ii)-dependent enzyme sequence. We anticipate that our approach can be readily expanded to further enzyme and transformation classes and will derisk the investigation and application of biocatalytic methods.
Biocatalysis, Organic chemistry
Mosaic anatomy in an early fossil squamate
Original Paper | Herpetology | 2025-09-30 20:00 EDT
Roger B. J. Benson, Stig A. Walsh, Elizabeth F. Griffiths, Zoe T. Kulik, Jennifer Botha, Vincent Fernandez, Jason J. Head, Susan E. Evans
Squamates (lizards and snakes) comprise almost 12,000 living species, with wide ecological diversity and a crown group that originated around 190 million years ago1,2. Conflict between morphology and molecular phylogenies indicates a complex pattern of anatomical transformations during early squamate evolution, which remains poorly understood owing to the scarcity of early fossil taxa1,3. Here we present Breugnathair elgolensis gen. et sp. nov., based on a new skeleton from the Middle Jurassic epoch (167 million years ago) of Scotland, which is among the oldest relatively complete fossil squamates. Breugnathair is placed in a new family, Parviraptoridae, an enigmatic group with potential importance for snake origins, that was previously known from very incomplete remains. It displays a mosaic of anatomical traits that is not present in living groups, with head and body proportions similar to varanids (monitor lizards) and snake-like features of the teeth and jaws, alongside primitive traits shared with early-diverging groups such as gekkotans. Phylogenetic analyses of multiple datasets return conflicting results, with parviraptorids either as early toxicoferans (and potentially stem snakes) or as stem squamates that convergently evolved snake-like dental and mandibular traits related to feeding. These findings indicate high levels of homoplasy and experimentation during the initial radiation of squamates and highlight the potential importance of convergent morphological transformations during deep evolutionary divergences.
Herpetology, Palaeontology
Doughnut of social and planetary boundaries monitors a world out of balance
Original Paper | Environmental social sciences | 2025-09-30 20:00 EDT
Andrew L. Fanning, Kate Raworth
The doughnut-shaped framework of social and planetary boundaries (the ‘Doughnut’) provides a concise visual assessment of progress towards the goal of meeting the needs of all people within the means of the living planet1,2,3. Here we present a renewed Doughnut framework with a revised set of 35 indicators that monitor trends in social deprivation and ecological overshoot over the 2000-2022 period. Although global gross domestic product (GDP) has more than doubled, our median results show a modest achievement in reducing human deprivation that would have to accelerate fivefold to meet the needs of all people by 2030. Meanwhile, the increase in ecological overshoot would have to stop immediately and accelerate nearly two times faster towards planetary boundaries to safeguard Earth-system stability by 2050. Disaggregating these global findings shows that the richest 20% of nations, with 15% of the global population, contribute more than 40% of annual ecological overshoot, whereas the poorest 40% of countries, with 42% of the global population, experience more than 60% of the social shortfall. These trends and inequalities reaffirm the case for overcoming the dependence of nations on perpetual GDP growth4,5 and reorienting towards regenerative and distributive economic activity–within and between nations–that assigns priority to human needs and planetary integrity.
Environmental social sciences, Planetary science
A human-specific regulatory mechanism revealed in a pre-implantation model
Original Paper | Gene regulation | 2025-09-30 20:00 EDT
Raquel Fueyo, Sicong Wang, Olivia J. Crocker, Tomek Swigut, Hiromitsu Nakauchi, Joanna Wysocka
Stem cell-based human embryo models offer a unique opportunity for functional studies of the human-specific features of development. Here we genetically and epigenetically manipulate human blastoids, a 3D embryo model of the blastocyst1, to investigate the functional effect of HERVK LTR5Hs, a hominoid-specific endogenous retrovirus, on pre-implantation development. We uncover a pervasive cis-regulatory contribution of LTR5Hs elements to the hominoid-specific diversification of the epiblast transcriptome in blastoids. Many of the LTR5Hs genomic insertions in the human genome are unique to our own species. We show that at least one such human-specific LTR5Hs element is essential for the blastoid-forming potential via enhancing expression of the primate-specific ZNF729 gene, encoding a KRAB zinc-finger protein. ZNF729 binds to GC-rich sequences, abundant at gene promoters associated with basic cellular functions, such as cell proliferation and metabolism. Despite mediating recruitment of TRIM28, at many of these promoters ZNF729 acts as a transcriptional activator. Together, our results illustrate how recently emerged transposable elements and genes can confer developmentally essential functions in humans.
Gene regulation, Stem cells
The Panoptes system uses decoy cyclic nucleotides to defend against phage
Original Paper | Biochemistry | 2025-09-30 20:00 EDT
Ashley E. Sullivan, Ali Nabhani, Daniel S. Izrailevsky, Kate Schinkel, Charlotte R. K. Hoffman, Laurel K. Robbins, Toni A. Nagy, Melissa L. Duncan, Hannah E. Ledvina, Annette H. Erbse, Emily M. Kibby, Uday Tak, David M. Dinh, Eirene Marie Q. Ednacot, Christy M. Nguyen, A. Maxwell Burroughs, L. Aravind, Aaron T. Whiteley, Benjamin R. Morehouse
Bacteria combat phage infection using antiphage systems and many systems generate nucleotide-derived second messengers upon infection that activate effector proteins to mediate immunity1. Phages respond with counter-defences that deplete these second messengers, leading to an escalating arms race with the host. Here we outline an antiphage system we call Panoptes that indirectly detects phage infection when phage proteins antagonize the nucleotide-derived second-messenger pool. Panoptes is a two-gene operon, optSE, wherein OptS is predicted to synthesize a nucleotide-derived second messenger and OptE is predicted to bind that signal and drive effector-mediated defence. Crystal structures show that OptS is a minimal CRISPR polymerase (mCpol) domain, a version of the polymerase domain found in type III CRISPR systems (Cas10). OptS orthologues from two distinct Panoptes systems generated cyclic dinucleotide products, including 2’,3’-cyclic diadenosine monophosphate (2’,3’-c-di-AMP), which we showed were able to bind the soluble domain of the OptE transmembrane effector. Panoptes potently restricted phage replication, but phages that had loss-of-function mutations in anti-cyclic oligonucleotide-based antiphage signalling system (CBASS) protein 2 (Acb2) escaped defence. These findings were unexpected because Acb2 is a nucleotide ‘sponge’ that antagonizes second-messenger signalling. Our data support the idea that cyclic nucleotide sequestration by Acb2 releases OptE toxicity, thereby initiating inner membrane disruption, leading to phage defence. These data demonstrate a sophisticated immune strategy that bacteria use to guard their second-messenger pool and turn immune evasion against the virus.
Biochemistry, Immunology, Microbiology, X-ray crystallography
A miniature CRISPR-Cas10 enzyme confers immunity by inhibitory signalling
Original Paper | Bacterial immune evasion | 2025-09-30 20:00 EDT
Erin E. Doherty, Benjamin A. Adler, Peter H. Yoon, Kendall Hsieh, Kenneth Loi, Emily G. Armbruster, Arushi Lahiri, Cydni S. Bolling, Xander E. Wilcox, Amogha Akkati, Anthony T. Iavarone, Joe Pogliano, Jennifer A. Doudna
Microbial and viral co-evolution has created immunity mechanisms involving oligonucleotide signalling that share mechanistic features with human antiviral systems1. In these pathways, including cyclic oligonucleotide-based antiphage signalling systems (CBASSs) and type III CRISPR systems in bacteria and cyclic GMP-AMP synthase-stimulator of interferon genes (cGAS-STING) in humans, oligonucleotide synthesis occurs upon detection of virus or foreign genetic material in the cell, triggering the antiviral response2,3,4. Here, in an unexpected inversion of this process, we show that the CRISPR-related enzyme mCpol synthesizes cyclic oligonucleotides constitutively as part of an active mechanism that represses a toxic effector. Cell-based experiments demonstrated that the absence or loss of mCpol-produced cyclic oligonucleotides triggers cell death, preventing the spread of viruses that attempt immune evasion by depleting host cyclic nucleotides. Structural and mechanistic investigation revealed mCpol to be a di-adenylate cyclase whose product, c-di-AMP, prevents toxic oligomerization of the effector protein 2TMβ. Analysis of cells by fluorescence microscopy showed that lack of mCpol allows 2TMβ-mediated cell death due to inner membrane collapse. These findings unveil a powerful defence strategy against virus-mediated immune suppression, expanding our understanding of the role of oligonucleotides in immunity.
Bacterial immune evasion, Biochemistry
Long-distance remote epitaxy
Original Paper | Synthesis and processing | 2025-09-30 20:00 EDT
Ru Jia, Yan Xin, Mark Potter, Jie Jiang, Zixu Wang, Hanxue Ma, Zhihao Zhang, Zhizhuo Liang, Lifu Zhang, Zonghuan Lu, Ruizhe Yang, Saloni Pendse, Yang Hu, Kai Peng, Yilin Meng, Wei Bao, Jun Liu, Gwo-Ching Wang, Toh-Ming Lu, Yunfeng Shi, Hanwei Gao, Jian Shi
Remote epitaxy, in which an epitaxial relation is established between a film and a substrate through remote interactions, enables the development of high-quality single crystalline epilayers and their transfer to and integration with other technologically crucial substates1,2. It is commonly believed that in remote epitaxy, the distance within which the remote interaction can play a leading part in the epitaxial process is less than 1 nm, as the atomically resolved fluctuating electric potential decays very rapidly to a negligible value after a few atomic distances3. Here we show that it is possible to achieve remote epitaxy when the epilayer-substrate distance is as large as 2-7 nm. We experimentally demonstrate long-distance remote epitaxy of CsPbBr3 film on an NaCl substrate, KCl film on a KCl substrate and ZnO microrods on GaN, and show that a dislocation in the GaN substrate exists immediately below every remotely epitaxial ZnO microrod. These findings indicate that remote epitaxy could be designed and engineered by means of harnessing defect-mediated long-distance remote interactions.
Synthesis and processing, Two-dimensional materials
Autoimmune response to C9orf72 protein in amyotrophic lateral sclerosis
Original Paper | Lymphocytes | 2025-09-30 20:00 EDT
Tanner Michaelis, Cecilia S. Lindestam Arlehamn, Emil Johansson, April Frazier, James D. Berry, Merit Cudkowicz, Namita A. Goyal, Christina Fournier, Allison Snyder, Justin Y. Kwan, Jody Crook, Elizabeth J. Phillips, Simon A. Mallal, John Ravits, Karen S. Marder, John Sidney, David Sulzer, Alessandro Sette
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by a progressive loss of motor neurons. Neuroinflammation is apparent in affected tissues, including increased T cell infiltration and activation of microglia, particularly in the spinal cord1,2. Autoimmune responses are thought to have a key role in ALS pathology, and it is hypothesized that T cells contribute to the rapid loss of neurons during disease progression3,4. However, until now there has been no reported target for such an autoimmune response. Here we show that ALS is associated with recognition of the C9orf72 antigen, and we map the specific epitopes that are recognized. We show that these responses are mediated by CD4+ T cells that preferentially release IL-5 and IL-10, and that IL-10-mediated T cell responses are significantly greater in donors who have a longer predicted survival time. Our results reinforce the previous hypothesis that neuroinflammation has an important role in ALS disease progression, possibly because of a disrupted balance of inflammatory and counter-inflammatory T cell responses4. These findings highlight the potential of therapeutic strategies aimed at enhancing regulatory T cells5, and identify a key target for antigen-specific T cell responses that could enable precision therapeutics in ALS.
Lymphocytes, Neurology
Spin squeezing in an ensemble of nitrogen-vacancy centres in diamond
Original Paper | Atomic and molecular physics | 2025-09-30 20:00 EDT
Weijie Wu, Emily J. Davis, Lillian B. Hughes, Bingtian Ye, Zilin Wang, Dominik Kufel, Tasuku Ono, Simon A. Meynell, Maxwell Block, Che Liu, Haopu Yang, Ania C. Bleszynski Jayich, Norman Y. Yao
Spin-squeezed states provide a seminal example of how the structure of quantum mechanical correlations can be controlled to produce metrologically useful entanglement1,2,3,4,5,6,7. These squeezed states have been demonstrated in a wide variety of quantum systems ranging from atoms in optical cavities to trapped ion crystals8,9,10,11,12,13,14,15,16. By contrast, despite their numerous advantages as practical sensors, spin ensembles in solid-state materials have yet to be controlled with sufficient precision to generate targeted entanglement such as spin squeezing. Here we report the experimental demonstration of spin squeezing in a solid-state spin system. Our experiments are performed on a strongly interacting ensemble of nitrogen-vacancy colour centres in diamond at room temperature, and squeezing (-0.50 ± 0.13 dB) below the noise of uncorrelated spins is generated by the native magnetic dipole-dipole interaction between nitrogen-vacancy centres. To generate and detect squeezing in a solid-state spin system, we overcome several challenges. First, we develop an approach, using interaction-enabled noise spectroscopy, to characterize the quantum projection noise in our system without directly resolving the spin probability distribution. Second, noting that the random positioning of spin defects severely limits the generation of spin squeezing, we implement a pair of strategies aimed at isolating the dynamics of a relatively ordered sub-ensemble of nitrogen-vacancy centres. Our results open the door to entanglement-enhanced metrology using macroscopic ensembles of optically active spins in solids.
Atomic and molecular physics, Quantum information, Quantum metrology, Quantum simulation
Nature Materials
Large moiré superstructure of stacked incommensurate charge density waves
Original Paper | Electronic properties and materials | 2025-09-30 20:00 EDT
B. Q. Lv, Yifan Su, Alfred Zong, Qiaomei Liu, Dong Wu, Noah F. Q. Yuan, Zhengwei Nie, Jiarui Li, Suchismita Sarker, Sheng Meng, Jacob P. C. Ruff, N. L. Wang, Nuh Gedik
Advances in heterostructure fabrication have opened new frontiers in moiré physics. Here we extend moiré engineering from artificially assembled thin flakes with mismatched lattice parameters to materials that host incommensurate orders, presenting a long-period moiré superlattice in a layered charge-density-wave compound, EuTe4. Using high-momentum-resolution X-ray diffraction, we found two coexisting incommensurate charge density waves with slightly mismatched in-plane wavevectors. The interaction between these two charge density waves leads to joint commensuration with the lattice and a moiré superstructure with a period of ~13.6 nm, offering key insights into the unique properties of EuTe4, such as the temperature-invariant incommensurate wavevectors and unconventional in-gap states. Owing to interlayer phase shifts, the moiré superstructure exhibits a clear thermal hysteresis, accounting for the large hysteresis in electrical resistivity and numerous metastable states. Our findings open new directions for moiré engineering based on incommensurate lattices and highlight the important role of interlayer ordering in stacked structures.
Electronic properties and materials, Structural properties
Amorphous phase-change memory alloy with no resistance drift
Original Paper | Materials science | 2025-09-30 20:00 EDT
Xiaozhe Wang, Ruobing Wang, Suyang Sun, Ding Xu, Chao Nie, Zhou Zhou, Chenyu Wen, Junying Zhang, Ruixuan Chu, Xueyang Shen, Wen Zhou, Zhitang Song, Jiang-Jing Wang, En Ma, Wei Zhang
Spontaneous structural relaxation is intrinsic to glassy materials due to their metastable nature. For phase-change materials, the resultant temporal change in electrical resistance seriously hampers neuromorphic computing applications. Here we report an ab-initio-calculation-informed design of amorphous phase-change materials composed of robust ‘molecule-like’ motifs, depriving the amorphous alloy of critical structural ingredients responsible for relaxation and, hence, resistance drift. We demonstrate amorphous CrTe3 thin films that display practically no resistance drift at any working temperature from -200 °C to 165 °C, and highlight the multilevel encoding ability via a hybrid opto-electronic approach. We further reveal that the same no-drift behaviour holds for melt-quenched amorphous CrTe3 in electronic devices. Moreover, the application potential of CrTe3 is testified by its incorporation in a vehicle with an automatic path-tracking function. Our work provides an alternative route to achieve requisite properties for potential phase-change neuromorphic computing via the judicious design of disordered phase-change materials.
Materials science, Metals and alloys
Nature Nanotechnology
Spatiotemporal-adaptive nanotherapeutics promote post-injury regeneration in ageing through metabolic modulation
Original Paper | Drug delivery | 2025-09-30 20:00 EDT
Kaiyu Liang, Lan Zhao, Shuheng Zhang, Luyu Zheng, Zheyuan Zhang, Shengyu Wang, Junxin Chen, Wenbin Xu, Weikai Wang, Hanshen Yang, Chenxin Song, Pengcheng Qiu, Chenchen Zhao, Weifeng Fang, Jinjin Zhu, Shunwu Fan, Zhaoming Liu, Ruikang Tang, Yueqi Zhao, Xiangqian Fang
In the elderly population, dysregulated cellular behaviour during the healing process impacts tissue regeneration after injury. Early in the regeneration process, pro-inflammatory macrophages contribute to immune imbalance, while in later stages, senescent stem cells reduce regenerative capacity. Here we demonstrate that nicotinamide adenine dinucleotide (NAD+) can reprogramme both types of dysfunctional cell. We developed a spatiotemporal-adaptive nanotherapeutic system for the delivery of NAD+ into selected cells during different phases of tissue repair. By replenishing intracellular NAD+ pools, this system reshapes the multicellular regeneration niche, by metabolically rewiring pro-inflammatory macrophages towards a pro-repair phenotype during the early phase, and enhancing the differentiation capacity of senescent stem cells at later stages. This strategy effectively restored impaired bone regeneration in osteoporotic mice and accelerated skin wound healing. Our work presents a spatiotemporal-adaptive nanomedicine platform that bridges cell metabolism, nanomedicine and regeneration therapy.
Drug delivery, Nanoparticles, Tissue engineering and regenerative medicine
Physical Review Letters
Indefinite Causal Order and Quantum Coordinates
Article | Cosmology, Astrophysics, and Gravitation | 2025-10-01 06:00 EDT
Anne-Catherine de la Hamette, Viktoria Kabel, Marios Christodoulou, and Časlav Brukner
Classically, the causal order of two timelike separated events and is fixed--either before or before . This is no longer true in quantum theory, where it is possible to encounter superpositions of causal orders. The quantum switch is one of the most prominent processes with indefinite caus…
Phys. Rev. Lett. 135, 141402 (2025)
Cosmology, Astrophysics, and Gravitation
Tidal Resonance in Binary Neutron Star Inspirals: A High-Precision Study in Numerical Relativity
Article | Cosmology, Astrophysics, and Gravitation | 2025-10-01 06:00 EDT
Hao-Jui Kuan, Kenta Kiuchi, and Masaru Shibata
We investigate the tidal resonance of the fundamental () mode in spinning neutron stars, robustly tracing the onset of the excitation to its saturation, using numerical relativity for the first time. We performed long-term ( orbits) fully relativistic simulations of a merger of two highly and re…
Phys. Rev. Lett. 135, 141403 (2025)
Cosmology, Astrophysics, and Gravitation
Nanoscale Mirrorless Superradiant Lasing
Article | Atomic, Molecular, and Optical Physics | 2025-10-01 06:00 EDT
Anna Bychek, Raphael Holzinger, and Helmut Ritsch
We predict collective free-space lasing in a dense nanoscopic emitter arrangement where dipole-dipole coupled atomic emitters synchronize their emission and exhibit lasing behavior without the need for an optical resonator. At the example of a subwavelength-spaced linear emitter chain with varying f…
Phys. Rev. Lett. 135, 143601 (2025)
Atomic, Molecular, and Optical Physics
Identification of Gapless Phases by a Twisting Operator
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Hang Su, Tengzhou Zhang, Yuan Yao, and Akira Furusaki
We propose a general necessary condition for a spin chain with SO(3) spin-rotation symmetry to be gapped. Specifically, we prove that the ground state(s) of an SO(3)-symmetric gapped spin chain must be spin singlet(s), and the expectation value of a twisting operator asymptotically approaches unity …
Phys. Rev. Lett. 135, 146502 (2025)
Condensed Matter and Materials
Emergent Inductance from Chiral Orbital Currents in a Bulk Ferrimagnet
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Gang Cao, Hengdi Zhao, Yu Zhang, Alex Fix, Tristan R. Cao, Dhruva Ananth, Yifei Ni, Gabriel Schebel, Rahul Nandkishore, Itamar Kimchi, Hua Chen, Feng Ye, and Lance E. DeLong
We report the discovery of a new form of inductance in the bulk ferrimagnet , which features strong spin-orbit coupling, large magnetic anisotropy, and pronounced magnetoelastic interactions. Below its Curie temperature (), hosts chiral orbital currents (COC) that circulat…
Phys. Rev. Lett. 135, 146504 (2025)
Condensed Matter and Materials
Ultrafast Nonequilibrium Enhancement of Electron-Phonon Interaction in $2{\mathrm{H}\text{-}\mathrm{MoTe}}_{2}$
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Nina Girotto Erhardt, Sotirios Fragkos, Dominique Descamps, Stéphane Petit, Michael Schüler, Dino Novko, and Samuel Beaulieu
Understanding nonequilibrium electron-phonon interactions at the microscopic level and on ultrafast timescales is a central goal of modern condensed matter physics. Combining time- and angle-resolved extreme ultraviolet photoemission spectroscopy with constrained density functional perturbation theo…
Phys. Rev. Lett. 135, 146904 (2025)
Condensed Matter and Materials
Unidirectional Giant Exciton Emission into a Photonic Waveguide
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Qifa Wang, Huan Luo, Chaojie Ma, Bingchang Zhang, Cheng Ji, Qinghong Yu, Guoxiang Chai, Yuxin Li, Chenyang Li, Shaojun Wang, Xuetao Gan, Kaihui Liu, Jianlin Zhao, and Fajun Xiao
Efficient coupling of nanolight sources into photonic waveguides is crucial for integrated photonics, quantum technologies, and biosensing. Practical implementations require light sources with simultaneous high brightness and unidirectional emission. However, it is fundamentally incompatible between…
Phys. Rev. Lett. 135, 146905 (2025)
Condensed Matter and Materials
Theory of Reversed Ripening in Active Phase Separating Systems
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-10-01 06:00 EDT
Jonathan Bauermann, Giacomo Bartolucci, Christoph A. Weber, and Frank Jülicher
The ripening dynamics in passive systems is governed by the theory of Lifshitz-Slyosov-Wagner (LSW). Here, we present an analog theory for reversed ripening in active systems. To derive the dynamic theory for the droplet size distribution, we consider a minimal ternary emulsion with one active react…
Phys. Rev. Lett. 135, 148201 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Light-Induced Phase Separation with Finite Wavelength Selection in Photophobic Microalgae
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-10-01 06:00 EDT
Isabelle Eisenmann, Alfredo L’Homme, Aliénor Lahlou, Sandrine Bujaldon, Thomas Le Saux, Benjamin Bailleul, Nicolas Desprat, and Raphaël Jeanneret
As with many motile microalgae, the freshwater species Chlamydomonas reinhardtii can detect light sources and adapt its motile behavior in response. Here, we show that suspensions of photophobic cells can be unstable to density fluctuations, as a consequence of shading interactions mediated by light…
Phys. Rev. Lett. 135, 148401 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Single-Ion Information Engine for Charging Quantum Battery
Article | Quantum Information, Science, and Technology | 2025-09-30 06:00 EDT
Jialiang Zhang, Pengfei Wang, Wentao Chen, Zhengyang Cai, Mu Qiao, Riling Li, Yingye Huang, Haonan Tian, Chuyang Luan, Hengchao Tu, Kaifeng Cui, Leilei Yan, Junhua Zhang, Jingning Zhang, Manhong Yung, and Kihwan Kim
Information engines produce mechanical work through measurement and adaptive control. For information engines, the principal challenge lies in how to store the generated work to the external load. Here, we report an experimental demonstration where quantized mechanical motion serves as a quantum bat…
Phys. Rev. Lett. 135, 140403 (2025)
Quantum Information, Science, and Technology
Probing Vector Chirality in the Early Universe
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-30 06:00 EDT
Junsup Shim, Ue-Li Pen, Hao-Ran Yu, and Teppei Okumura
Cosmological simulations show that a left-right asymmetry in the early Universe could leave a mark in the distribution of galaxy rotations.
Phys. Rev. Lett. 135, 141002 (2025)
Cosmology, Astrophysics, and Gravitation
Resummation of Universal Tails in Gravitational Waveforms
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-30 06:00 EDT
Mikhail M. Ivanov, Yue-Zhou Li, Julio Parra-Martinez, and Zihan Zhou
We present a formula for the universal anomalous scaling of the multipole moments of a generic gravitating source in classical general relativity. We derive this formula in two independent ways using effective field theory methods. First, we use the absorption of low-frequency gravitational waves by…
Phys. Rev. Lett. 135, 141401 (2025)
Cosmology, Astrophysics, and Gravitation
New Framework for Classical Double Copies
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-30 06:00 EDT
Brian Kent and Aaron Zimmerman
The double copy relates gauge and gravitational theories, with widespread application to quantum scattering amplitudes and classical perturbative results. It also connects exact classical solutions of Abelian gauge and gravitational theories in a small number of specific examples, known as classical…
Phys. Rev. Lett. 135, 141501 (2025)
Cosmology, Astrophysics, and Gravitation
Boundary Criticality for the Gross-Neveu-Yukawa Models
Article | Particles and Fields | 2025-09-30 06:00 EDT
Huan Jiang, Yang Ge, and Shao-Kai Jian
We study the boundary criticality for the Gross-Neveu-Yukawa (GNY) models. Employing interacting Dirac fermions on a honeycomb lattice with armchair boundaries, we use determinant quantum Monte Carlo simulation to uncover rich boundary criticalities at the quantum phase transition to a charge densit…
Phys. Rev. Lett. 135, 141602 (2025)
Particles and Fields
Dark-Matter-Electron Detectors for Dark-Matter-Nucleon Interactions
Article | Particles and Fields | 2025-09-30 06:00 EDT
Sinéad M. Griffin, Guy Daniel Hadas, Yonit Hochberg, Katherine Inzani, and Benjamin V. Lehmann
In a seminal paper now a decade old, it was shown that dark-matter detectors geared at probing interactions with nucleons could also be used to probe dark-matter interactions with electrons. In this Letter, we show that new detector concepts designed to probe dark-matter-electron interactions at low…
Phys. Rev. Lett. 135, 141803 (2025)
Particles and Fields
Quarkonium Spectroscopy in the Quark-Gluon Plasma
Article | Nuclear Physics | 2025-09-30 06:00 EDT
Zhanduo Tang, Biaogang Wu, Andrew Hanlon, Swagato Mukherjee, Peter Petreczky, and Ralf Rapp
The properties of bound states are fundamental to hadronic spectroscopy and play a central role in the transition from hadronic matter to a quark-gluon plasma (QGP). In a strongly coupled QGP (sQGP), the interplay of temperature, binding energy, and large collisional widths of the partons poses form…
Phys. Rev. Lett. 135, 142302 (2025)
Nuclear Physics
Partial-Wave Resolved Spin-Orbit Dynamics
Article | Atomic, Molecular, and Optical Physics | 2025-09-30 06:00 EDT
Wankai Li, Jingxuan Zhang, Yang Jin, Dongdong Zhang, Dajun Ding, and Kiyoshi Ueda
A novel projective measurement technique utilizing conventional photoelectron velocity-map imaging to probe the spatial part of the wave function by projecting it into momentum space is demonstrated. Oscillations between the states and are observed with no detectable d…
Phys. Rev. Lett. 135, 143201 (2025)
Atomic, Molecular, and Optical Physics
No Time for Surface Charge: How Bulk Conductivity Hides Charge Patterns from Kelvin Probe Force Microscopy in Contact-Electrified Surfaces
Article | Condensed Matter and Materials | 2025-09-30 06:00 EDT
Felix Pertl, Isaac C. D. Lenton, Tobias Cramer, and Scott Waitukaitis
A new experiment on static electricity casts doubt on previous ones.
Phys. Rev. Lett. 135, 146202 (2025)
Condensed Matter and Materials
Anyon Braiding on the Single Edge of a Fractional Quantum Hall State
Article | Condensed Matter and Materials | 2025-09-30 06:00 EDT
Flavio Ronetti, Noé Demazure, Jérôme Rech, Thibaut Jonckheere, Benoît Grémaud, Laurent Raymond, Masayuki Hashisaka, Takeo Kato, and Thierry Martin
Anyons are quasiparticles with fractional statistics, bridging between fermions and bosons. We propose an experimental setup to measure the statistical angle of topological anyons emitted from a quantum point contact (QPC) source. The setup involves an -shaped junction along a fractional quantum Ha…
Phys. Rev. Lett. 135, 146601 (2025)
Condensed Matter and Materials
Terahertz-Induced Tunnel Ionization Drives Coherent Raman-Active Phonon in Bismuth
Article | Condensed Matter and Materials | 2025-09-30 06:00 EDT
Bing Cheng, Patrick L. Kramer, Mariano Trigo, Mengkun Liu, Ctirad Uher, David A. Reis, Zhi-Xun Shen, Jonathan A. Sobota, and Matthias. C. Hoffmann
Driving coherent lattice motion with THz pulses has emerged as a novel pathway for achieving dynamic stabilization of exotic phases that are inaccessible in equilibrium quantum materials. In this Letter, we present a previously unexplored mechanism for THz excitation of Raman-active phonons. We show…
Phys. Rev. Lett. 135, 146901 (2025)
Condensed Matter and Materials
Strongly Entangled Kondo and Kagome Lattices and the Emergent Magnetic Ground State in Heavy-Fermion Kagome Metal ${\mathrm{YbV}}{6}{\mathrm{Sn}}{6}$
Article | Condensed Matter and Materials | 2025-09-30 06:00 EDT
Rui Lou et al.
Applying angle-resolved photoemission spectroscopy and density functional theory calculations, we present compelling spectroscopic evidence demonstrating the intertwining and mutual interaction between the Kondo and kagome sublattices in heavy-fermion intermetallic compound . We reveal the Yb…
Phys. Rev. Lett. 135, 146902 (2025)
Condensed Matter and Materials
Pushing Photons with Electrons: Observation of the Polariton Drag Effect
Article | Condensed Matter and Materials | 2025-09-30 06:00 EDT
D. M. Myers, Q. Yao, H. Alnatah, S. Mukherjee, B. Ozden, J. Beaumariage, L. N. Pfeiffer, K. West, and D. W. Snoke
We show the direct effect of free electrons colliding with polaritons, changing their momentum. The result of this interaction of the electrons with the polaritons is a change in the angle of emission of the photons from our cavity structure. Because the experiment is a photon-in, photon-out system,…
Phys. Rev. Lett. 135, 146903 (2025)
Condensed Matter and Materials
Physical Review X
Radon Removal in XENONnT down to the Solar Neutrino Level
Article | | 2025-09-30 06:00 EDT
E. Aprile et al. (XENON Collaboration)
Using advanced cryogenic distillation, the XENONnT experiment cuts radon levels in its 10-tonne liquid xenon detector to just 430 atoms per tonne, enabling ultrapure conditions for detecting faint dark matter signals.
Phys. Rev. X 15, 031079 (2025)
arXiv
Metal-insulator transition in a CuO chain created by Kondo interaction
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Todor M. Mishonov, Albert M. Varonov, Kaloian D. Lozanov
Over twenty years ago Alexei Abrikosov [A.A. Abrikosov, Metal-insulator transition in layered cuprates (SDW model), Physica C: Supercond. Vol. 391, 2, 147-159 (2003)] considered the Spin-Density-Waves (SDW) model for the metal-insulator transition in layered cuprates. In one of those cuprates, YBa$ _2$ Cu$ _3$ O$ _{7-\delta}$ , there are one-dimensional (1D) CuO chains of copper and oxygen ions. In the present work we consider the metal-insulator transition in the model case of a 1D CuO chain in the regime of half-filling of the band. Our model is essentially the same, but as an exchange interaction causing the metal-insulator transition, we consider Kondo-Zener two-electron exchange, which successfully describes many of the electronic properties of the layered cuprates.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 2 figures, 47 references
Mechanisms of Matter: Language Inferential Benchmark on Physicochemical Hypothesis in Materials Synthesis
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Yingming Pu, Tao Lin, Hongyu Chen
The capacity of Large Language Models (LLMs) to generate valid scientific hypotheses for materials synthesis remains largely unquantified, hindered by the absence of benchmarks probing physicochemical logics reasoning. To address this, we introduce MatterMech, a benchmark for evaluating LLM-generated hypotheses across eight nanomaterial synthesis domains. Our analysis reveals a critical disconnect: LLMs are proficient in abstract logic yet fail to ground their reasoning in fundamental physicochemical principles. We demonstrate that our proposed principle-aware prompting methodology substantially outperforms standard Chain-of-Thought, enhancing both hypothesis accuracy and computational efficiency. This work provides a methodological framework to advance LLMs toward reliable scientific hypothesis generation in materials science. The MatterMech benchmark and associated code is publicly available at \href{this https URL}{GitHub}.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
High-efficiency Pt75Au25-based spintronic terahertz emitters
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Wenlu Shi, Gene D. Nelson, Han-Hsuan Wu, Yiwei Ju, Xiaoqing Pan, Wilson Ho, Ilya N. Krivorotov
Spintronic terahertz emitters (STEs) generate broadband THz radiation via ultrafast spin-charge conversion in magnetic multilayers, offering spectral coverage beyond that of photoconductive antennas and nonlinear optical crystals. Here, we demonstrate a new type of STE based on PtxAu100-x alloy that achieves signifi- cantly higher THz output power than widely used Pt-based devices. Alloy composition and layer thickness tuning yield Pt75Au25 as the optimal alloy providing a 30 % increase in THz power in CoFeB/Pt75Au25 bilayer STEs compared to the optimized CoFeB/Pt reference STE. In W/CoFeB/Pt75Au25 trilayer STEs, we observe a 10 % higher THz power than in the optimized W/CoFeB/Pt trilayer. The STE efficiency is reduced upon annealing for both Pt75Au25- and Pt-based STEs due to formation of interfacial alloys. Our results establish Pt75Au25 as a promising platform for high-performance STEs, where its giant spin Hall effect significantly enhances efficiency over conventional Pt-based devices.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
7 pages, 4 figures
Topological non-Abelian Gauge Structures in Cayley-Schreier Lattices
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
Zoltán Guba, Robert-Jan Slager, Lavi K. Upreti, Tomáš Bzdušek
Recently, novel crystalline constructions known as Cayley-Schreier lattices have been suggested as a platform for realizing arbitrary gauge fields in synthetic crystals with real hopping amplitudes. We show that Cayley-Schreier lattices can naturally give rise to implementable lattice systems that incorporate non-Abelian gauge structures transforming into a space-group symmetry. We show that the symmetry sectors can, moreover, be interpreted as blocks of spin models that can effectively realize a wealth of different topological invariants in a single setup. We underpin these general results with concrete models and show how they can be implemented in current experimental platforms. Our work sets the stage for a systematic investigation of topological insulators and metals with non-Abelian gauge structures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Mathematical Physics (math-ph)
11 pages (including 5 figures, bibliography, and supplementary information file)
Strong-coupling superconductivity near Gross-Neveu quantum criticality in Dirac systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Veronika C. Stangier, Daniel E. Sheehy, Jörg Schmalian
We study two-dimensional massless Dirac fermions at neutrality, coupled to bosonic modes through a Yukawa interaction. We then examine the intriguing possibility that such a system, devoid of carriers at zero temperature, might nevertheless exhibit superconductivity. Remarkably, we find that superconductivity emerges in the vicinity of Gross-Neveu quantum criticality, provided the fermions cease to behave as well-defined quasiparticles, that is, once their anomalous dimension in the normal state becomes sufficiently large. In other words, well-defined fermions do not superconduct, whereas ill-defined ones do. We analyze four symmetry-distinct bosonic modes, each capable of driving normal-state criticality and, in three of the four cases, giving rise to a distinct superconducting phase. While phase fluctuations are strong in this regime, we argue that they do not destroy the superconducting state. We further characterize the resulting pairing states for a concrete Dirac model of spin-orbit coupled systems with orbitals of different parity. Our results are obtained using the SYK-inspired framework for Dirac systems introduced by Kim et al.[1], which provides a controlled approach to the strongly coupled regime of Dirac fluids near Gross-Neveu criticality.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con), High Energy Physics - Theory (hep-th)
15 pages, 7 figures
The Sound of Electrons Shattering: Current Noise Composition Laws for Electron Fractionalization
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Adarsh S. Patri, Josephine J. Yu, Yi-Ming Wu, T. Senthil, Hart Goldman
We develop a theory of the non-equilibrium current response for metallic systems near quantum critical points where electronic quasiparticles fractionalize, such as systems near continuous metal-insulator transitions or composite Fermi liquid to Fermi liquid transitions. Applying a generalized response theory within a Keldysh path integral framework, we derive a non-perturbative current noise composition law, wherein the total noise is the sum of the noise of each fractionalized constituent (bosonic holons and fermionic spinons), weighted by their respective resistivities. We demonstrate that the formally derived composition relations can be interpreted in terms of a simple analogy with resistors in series. We leverage this composition rule near certain quantum critical points to show that the shot noise can be suppressed in long nanowires as compared to Fermi liquid expectations due to the collusion of quantum criticality with fractionalization.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 + 6 pages; 1 figure
Chiral charge conservation and ballistic magnetotransport in a disordered Weyl semimetal
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
We demonstrate that in an ideal Weyl semimetal, in which the Fermi energy coincides with the band-touching nodes, weak direct inter-nodal scattering is irrelevant and, as a result, the chiral charge is (almost) exactly conserved. This leads to an experimentally-observable effect: in an applied magnetic field, the charge transport along the field becomes purely ballistic, with the conductance given by $ e^2/h$ per magnetic flux quantum through the sample cross-section. This is the strongest experimental manifestation of nontrivial topology in Weyl and Dirac semimetals.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages
Origin of Spin Stripes in Bilayer Nickelate La$_3$Ni$_2$O$_7$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Hao-Xin Wang, Hanbit Oh, Tobias Helbig, Bai Yang Wang, Jiarui Li, Yijun Yu, Harold Y. Hwang, Hong-Chen Jiang, Yi-Ming Wu, S. Raghu
The bilayer nickelate La$ _3$ Ni$ _2$ O$ 7$ has emerged as a new high temperature superconductor. We propose and study a microscopic Hamiltonian that addresses the interplay of lattice structure and magnetism in this system. Using state-of-the-art density matrix renormalization group calculations, we show that $ (\pi/2,\pi/2)$ spin stripe order emerges in our model and exhibits a hidden quasi-one dimensionality. The spin stripe order occurs over a range of electron concentrations, but requires a sizable Hund’s coupling $ J_H$ . Our model exhibits superconducting tendency only when the interlayer antiferromagnetic coupling $ J\bot$ becomes sufficiently large, which naturally occurs under pressure. Our study unveils the microscopic origin of both the unusual spin stripes and superconductivity in La$ _3$ Ni$ _2$ O$ _7$ , and highlights the indispensable role of Hund’s coupling $ J_H$ in this system.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
8 pages with 5 figures
Diffusion with doubly stochastic resetting
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
Maxence Arutkin, Shlomi Reuveni
Diffusion with stochastic resetting, instantaneous returns of a diffusing particle to a reference point, creates a stationary probability distribution. The paradigm is extended here to a doubly stochastic protocol in which the resetting rate itself fluctuates in time and relaxes on its own timescale. An exact steady-state solution reveals three spatial regimes: a fluctuation-dominated core near the origin, a power-law regime at intermediate distances, and a far-field exponential decay fixed by the rate-relaxation time. These results expose how the instantaneous rate, mean rate, and relaxation time come together to determine the non-equilibrium steady state.
Statistical Mechanics (cond-mat.stat-mech)
13 pages, 3 figures
Design Principles for Topological Thermoelectrics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Brian Skinner, Poulomi Chakraborty, Joshua Scales, Joseph P. Heremans
Conventional metals, insulators, and semimetals are constrained by fundamental limitations in terms of their thermoelectric performance. Topological materials offer certain features that allow them to circumvent these constraints, and potentially to form the basis for thermoelectric devices with unprecedented efficiency. In this article we review the thermoelectric performance of topological materials, focusing specifically on nodal semimetals, such as Weyl and nodal-line semimetals. We discuss how certain unique ``topological’’ features of these materials – namely their topologically protected band touching points, electron-hole degenerate lowest Landau level, and Berry curvature – allow them to exhibit thermoelectric properties that go beyond what is possible in conventional materials, particularly in the presence of an applied magnetic field. We focus our discussion on the goal of achieving large figure of merit $ zT$ , and for each material class we summarize optimal \emph{design principles} for selecting materials that maximize thermoelectric efficiency.
We then use these optimal design principles to design and implement a high-throughput database search for topological semimetals that are promising as thermoelectrics. In addition to highlighting a number of materials that are already known to have large magnetothermoelectric effects, our search uncovers twelve additional materials that are especially promising for near-future experiments.
Materials Science (cond-mat.mtrl-sci)
review article: 27 pages, 9 figures, 4 tables. Suggestions and comments welcome
Spatial correlations in SIS processes on regular random graphs
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
Alexander Leibenzon, Samuel W.S. Johnson, Ruth E. Baker, Michael Assaf
In network-based SIS models of infectious disease transmission, infection can only occur between directly connected individuals. This constraint naturally gives rise to spatial correlations between the states of neighboring nodes, as the infection status of connected individuals becomes interdependent. Although mean-field approximations are commonly invoked to simplify disease forecasting on networks, they fail to account for these correlations by assuming that infectious individuals are well-mixed within a population, leading to inaccurate predictions of infection numbers over time. As such, the development of mathematical frameworks that account for spatially correlated infections is of great interest, as they offer a compromise between accurate disease forecasting and analytic tractability. Here, we use existing corrections to mean-field theory on the regular lattice to construct a more general framework for equivalent corrections on regular random graph topologies. We derive and simulate a system of ordinary differential equations for the time evolution of the spatial correlation function at various geodesic distances on random networks, and use solutions to this hierarchy of ordinary differential equations to predict the global infection density as a function of time, finding good agreement with corresponding numerical simulations. Our results constitute a substantial development on existing corrections to mean-field theory for infectious individuals in SIS processes and provide an in-depth characterization of how structural randomness in networks affects the dynamical trajectories of infectious diseases on networks.
Statistical Mechanics (cond-mat.stat-mech), Computational Physics (physics.comp-ph), Populations and Evolution (q-bio.PE)
10 pages, 5 figures
Electropolishing-Induced Topographic Defects in Niobium: Insights and Implications for Superconducting Radio Frequency Applications
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Oleksandr Hryhorenko, Anne-Marie Valente-Feliciano, Eric M. Lechner
Electropolishing is the premier surface preparation method for high-Q, high-gradient superconducting RF cavities made of Nb. This leaves behind an apparently smooth surface, yet the achievable peak magnetic fields fall well below the superheating field of Nb, in most cases. In this work, the ultimate surface finish of electropolishing was investigated by studying its effect on highly polished Nb samples. Electropolishing introduces high slope angle sloped-steps at grain boundaries. The magnetic field enhancement and superheating field suppression factors associated with such a geometry are calculated in the London theory. Despite the by-eye smoothness of electropolished Nb, such defects compromise the stability of the low-loss Meissner state, likely limiting the achievable peak accelerating fields in superconducting RF cavities. Finally, the impact of surface roughness on impurity diffusion is investigated which can link surface roughness to the effectiveness of heat treatments like low-temperature baking or nitrogen infusion in the vortex nucleation or hydride hypotheses. Surface roughness tends to decrease the effective dose of impurities as a result of the expansion of impurities into regions with greater internal angle. The effective dose of impurities can be protected by minimizing slope angles and step heights, ensuring uniformity.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Accelerator Physics (physics.acc-ph), Applied Physics (physics.app-ph)
Scalable Boltzmann Generators for equilibrium sampling of large-scale materials
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
Maximilian Schebek, Jutta Rogal
The use of generative models to sample equilibrium distributions of many-body systems, as first demonstrated by Boltzmann Generators, has attracted substantial interest due to their ability to produce unbiased and uncorrelated samples in `one shot’. Despite their promise and impressive results across the natural sciences, scaling these models to large systems remains a major challenge. In this work, we introduce a Boltzmann Generator architecture that addresses this scalability bottleneck with a focus on applications in materials science. We leverage augmented coupling flows in combination with graph neural networks to base the generation process on local environmental information, while allowing for energy-based training and fast inference. Compared to previous architectures, our model trains significantly faster, requires far less computational resources, and achieves superior sampling efficiencies. Crucially, the architecture is transferable to larger system sizes, which allows for the efficient sampling of materials with simulation cells of unprecedented size. We demonstrate the potential of our approach by applying it to several materials systems, including Lennard-Jones crystals, ice phases of mW water, and the phase diagram of silicon, for system sizes well above one thousand atoms. The trained Boltzmann Generators produce highly accurate equilibrium ensembles for various crystal structures, as well as Helmholtz and Gibbs free energies across a range of system sizes, able to reach scales where finite-size effects become negligible.
Statistical Mechanics (cond-mat.stat-mech), Machine Learning (cs.LG)
Kinetic Monte Carlo prediction of the morphology of pentaerythritol tetranitrate
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Jacob Jeffries, Himanshu Singh, Romain Perriot, Christian Negre, Antonio Redondo, Enrique Martinez
In this work, we develop an atomistic, graph-based kinetic Monte Carlo (KMC) simulation routine to predict crystal morphology. Within this routine, we encode the state of the supercell in a binary occupation vector and the topology of the supercell in a simple nearest-neighbor graph. From this encoding, we efficiently compute the interaction energy of the system as a quadratic form of the binary occupation vector, representing pairwise interactions. This encoding, coupled with a simple diffusion model for adsorption, is then used to model evaporation and adsorption dynamics at solid-liquid interfaces. The resulting intermolecular interaction-breaking energies are incorporated into a kinetic model to predict crystal morphology, which is implemented in the open-source Python package Crystal Growth Kinetic Monte Carlo (cgkmc). We then apply this routine to pentaerythritol tetranitrate (PETN), an important energetic material, showing excellent agreement with the attachment energy model.
Materials Science (cond-mat.mtrl-sci)
10 pages, 3 figures
Non-Gaussian statistics of concentration fluctuations in free liquid diffusion
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
Marco Bussoletti, Mirko Gallo, Amir Jafari, Gregory L. Eyink
We show that the three-point skewness of concentration fluctuations is non-vanishing in free liquid diffusion, even in the limit of vanishingly small mean concentration gradients. We exploit a high-Schmidt reduction of nonlinear Landau-Lifshitz hydrodynamics for a binary fluid, both analytically and by a massively parallel Lagrangian Monte Carlo simulation. Non-Gaussian statistics result from nonlinear coupling of concentration fluctuations to thermal velocity fluctuations, analogous to the turbulent advection of a passive scalar. Concentration fluctuations obey no central limit theorem, counter to the predictions of macroscopic fluctuation theory for generic diffusive systems.
Statistical Mechanics (cond-mat.stat-mech), Fluid Dynamics (physics.flu-dyn)
Contact Forces in Microgel Suspensions
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Fran Ivan Vrban (1), Antonio Šiber (2 and 3), Primož Ziherl (1 and 3) ((1) Faculty of Mathematics and Physics, University of Ljubljana, Slovenia, (2) Institute of Physics, Zagreb, Croatia, (3) Jožef Stefan Institute, Ljubljana, Slovenia)
Within a model where micrometer-size soft colloidal particles are viewed as liquid drops, we theoretically study the contact interaction between them. We compute the exact deformation energy across a broad range of indentations and for various model parameters, and we show that it can be reproduced using truncated superball and spheropolyhedral variational shapes in the attractive and the repulsive regime, respectively. At large surface tensions representative of microgels, this energy is pairwise additive well beyond small indentations and can be approximated by a power-law dependence on indentation with an exponent around 2.
Soft Condensed Matter (cond-mat.soft)
5 pages, 4 figures. Supplementary material available (21 pages, 17 figures). To be submitted in Physical Review Letters
Hydrodynamic interactions destroy motility-induced phase separation in active suspensions
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Motility-Induced Phase Separation (MIPS) is a distinctive phenomenon in active matter that arises from its inherent non-equilibrium nature. Despite recent progress in understanding MIPS in dry active systems, it has been debated whether MIPS can be observed in wet systems in which fluid-mediated hydrodynamic interactions (HI) are present. We use theory and large-scale {\it Active Fast Stokesian Dynamics} simulations of the so-called squirmer model to show that collision-induced pusher force dipoles, which are present even for the simplest neutral squirmers (stealth swimmers), destroy MIPS when HI are included. Both rotational and translational HI independently suppress phase separation: rotation by shortening a swimmer’s persistence length (and thus reducing the swim pressure), translation by a confinement-scale advective fluid flow. We further clarify that collisional dipoles between swimmers and boundaries can generate attractive flows that promote particle aggregation observed in some previous simulations and experiments. Finally, we show how to recover MIPS in fluidic environments by tuning the magnitude of the HI through brush-like surface coatings on the active particles.
Soft Condensed Matter (cond-mat.soft)
Spin and Orbital Edelstein effect in gated monolayer transition metal dichalcogenides
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
The Edelstein effect consists of the non-equilibrium accumulation of magnetization in response to an applied electric field in systems with broken inversion symmetry. While the spin Edelstein effect (SEE), originating from spin moments, is well established, its orbital counterpart, where magnetization arises from orbital moment, has only recently begun to attract attention. In this work, we investigate the orbital Edelstein effect (OEE) in gated monolayer transition-metal dichalcogenides (TMDs), such as MoS2, by using first-principles density-functional calculations with both electron and hole doping. The gate-induced broken mirror symmetry produces a Rashba-type chiral spin/orbital angular momentum texture, which in turn leads to the Edelstein effect in response to an applied in-plane electric field. We find that for electron doping the Edelstein response is dominated by the orbital channel, whereas for hole doping the orbital and spin contributions are comparable. For the case of hole doping, both OEE and SEE are strongly enhanced by a small amount of strain, due to strain-driven shifts between the Gamma and K/K’ valley energies. We derive analytical expressions for the spin and orbital Edelstein susceptibilities and evaluate their magnitudes from first-principles. Remarkably, the predicted OEE in gated monolayer TMDs is an order of magnitude larger than values reported in previously studied systems. Our results identify TMDs as promising platforms for studying the orbital Edelstein effect and highlight their potential applications in spintronics devices.
Materials Science (cond-mat.mtrl-sci)
Quantum geometric origins of the orbital degrees of freedom of hybrid bosonic quasiparticles in magnetic systems
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
D. Quang To, Dai Q. Ho, Joshua M. O. Zide, Lars Gundlach, M. Benjamin Jungfleisch, Garnett W. Bryant, Anderson Janotti, Matthew F. Doty
The orbital degree of freedom has recently attracted significant attention due to the novel phenomena it enables in condensed matter systems. However, the interpretation of the orbital degree of freedom in bosonic quasiparticles remains conceptually ambiguous and the mechanisms governing the transfer of orbital angular moment (OAM) between distinct quasiparticles, such as magnons and phonons, are not yet fully understood. We investigate orbital dynamics in bosonic systems and identify two origins of OAM: (i) global rotational motion of the system, and (ii) the quantum geometry of wavefunctions. Focusing on the latter, we study strongly coupled magnon-phonon systems in two-dimensional antiferromagnets as a test case. We uncover finite OAM arising from quantum geometric effects via two mechanisms: (a) time-parity symmetry breaking, yielding intra band OAM, and (b) interband coupling, generating interband OAM. We propose that an electrical detection scheme based on the transverse voltage generated by hybrid magnon phonon modes can be used to experimentally probe the bosonic orbital degree of freedom. Our results establish a foundation for the emerging field of phonon orbitronics, providing both a conceptual bridge between phonon and magnon orbitronics and a tool for better understanding magnon-polarons. They also advance a unified framework for harnessing orbital degrees of freedom in bosonic systems and pave the way toward electrical control of magnetization and phononic transport.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
8 pages, 3 figures
Rotational migration in human pancreatic ductal organoids depends on actin and myosin activity
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Gengqiang Xie, Chaity Modak, Olalekan H Usman, Raphael WF Tan, Nicole Coca, Gabriela De Jesus, Yue Julia Wang, D. Thirumalai, Xin Li, Jerome Irianto
Rotational migration is one specific form of collective cell migration when epithelial cells are confined in a spherical geometry, such as in the epithelial acini. This tissue-level rotation motion is crucial for the morphogenesis of multiple epithelial systems. Here, we introduce a new primary human model for the study of rotational migration, pancreatic ductal organoids. Live imaging revealed the persistent rotation of the organoids over time. By tracking the nuclei, the three- dimensional trajectory of the cellular movement was reconstructed and the velocity of the rotation was quantified. The presence of focal adhesion clusters and prominent actin stress fibers were observed at the basal side of the organoids, suggesting the interactions between the cells and the surrounding extracellular matrix. Finally, our inhibition study showed the dependence of pancreatic ductal organoid rotational migration on myosin activity, actin polymerization, and actin branching. We hope that this model will enable future studies with human primary cells, which are more faithful to normal epithelial cells.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph), Cell Behavior (q-bio.CB)
37 pages, 5 main figures, 5 SI figures, to be appear in Communications Biology
Electric-field control of pure spin photocurrent in germanene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
Yaqing Yang, Zhen Zhang, Liwen Zhang, Liantuan Xiao, Suotang Jia, Jun Chen, Lei Zhang
The electrical control of pure spin current remains a central challenge in spintronics, particularly in time-reversal symmetric systems composed of nonmagnetic elements, where spin and electric fields interact only indirectly. In this work, we develop a theoretical framework for electrically tuning pure spin photocurrent in two-dimensional materials with time-reversal symmetry via a gate electric field. Through theoretical analysis, we demonstrate that in systems with spin-orbit coupling and in-plane mirror symmetry, an out-of-plane electric field induces spin splitting and reversal in the band structure near the Fermi energy, enabling magnitude control and direction reversal of the pure spin photocurrent. To validate this mechanism, we perform first-principles calculations on germanene, an experimentally realized two-dimensional material. Beyond amplitude modulation, we reveal that reversing the direction of the applied electric field leads to a corresponding reversal of the pure spin photocurrent. Furthermore, we show that the pure spin photocurrent can be tuned by varying the photon energy and the incident angle of light, providing additional degrees of control over spin transport. These findings establish a robust strategy for electric-field-controlled pure spin transport in two-dimensional materials, offering new possibilities for the development of optospintronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optics (physics.optics)
Lithium depth profiling in NMC/Graphite commercial coin cells under high C-rate cycling
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Naisargi Kanabar, Seiichiro Higashiya, Daniele Cherniak, Devendra Sadana, Stephen Bedell, Haralabos Efstathiadis
This study examines lithium distribution and its evolution in both anode and cathode materials of commercial lithium-ion coin cells subjected to high C-rate cycling, providing insights into lithium loss, trapping, and plating mechanisms. Cells were cycled at 1C to 3C rates, and post-mortem analysis were performed using Li nuclear reaction Analysis (Li-NRA), x-ray diffraction (XRD), and scanning electron microscopy (SEM) equipped with energy-dispersive x-ray spectroscopy (EDS). Li-NRA using the resonant nuclear reaction between an incident high-energy proton and lithium was used to measure the depth distribution of Li in the cathode and anode layers. The Li-NRA analysis revealed a surface lithium peak on the anode, likely associated with SEI formation and lithium plating, while the cathode exhibited a decrease in lithium content by ~19.7%. XRD analysis of the cathode showed a contraction of the c-lattice parameter and peak shifts consistent with lithium depletion and structural deformation, supported by SEM imaging. In contrast, the dead graphite anode shows an enhanced peak at 43.3°, which corresponds to the presence of metallic lithium or possibly Cu. 3-C rate cycling also led to capacity fade and an increase in internal resistance, highlighting the impact of lithium plating on cell performance.
Materials Science (cond-mat.mtrl-sci)
Probing phase transitions in non-Hermitian systems with quantum entanglement
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
We study the quantum entanglement and quantum phase transition of the non-Hermitian anisotropic spin-1/2 XY model and XXZ model with the staggered imaginary field by analytical methods and numerical exact diagonalization, respectively. Various entanglement measures, including concurrence, negativity, mutual information, and quantum coherence, and both biorthogonal and self-normal quantities are investigated. Both the biorthogonal and self-normal entanglement quantities, except the biorthogonal concurrence, are found to be capable of detecting the first-order and $ \mathcal{PT}$ transitions in the XXZ model, as well as the Ising and $ \mathcal{RT}$ transitions in the XY model. In addition, we introduce the unconstrained concurrence and demonstrate its effectiveness in detecting these transitions. On the other hand, the Beresinskii-Kosterlitz-Thoules (BKT) transition in the XXZ model is revealed through concurrence and negativity at small non-Hermiticity strengths. Notably, the critical points observed in the Hermitian limit evolve into exceptional points as the strength of the non-Hermiticity increases. Furthermore, we find that the first-order transition survives up to a higher non-Hermiticity strength compared to the BKT transition within the $ \mathcal{PT}$ -symmetric regime of the XXZ model.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
14 pages, 9 figures
Dark Soliton Formation as a Dark-State Phase Transition in a Dissipative Superfluid Chain
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-01 20:00 EDT
Robbe Ceulemans, Samuel E. Begg, Matthew J. Davis, Michiel Wouters
We identify and characterize a first-order dark-state phase transition between a discrete dark soliton and a uniform superfluid in a Bose-Hubbard chain with a single lossy site. Using classical-field (truncated-Wigner) simulations together with a Bogoliubov stability analysis, we show that the dark-state nature of the soliton suppresses fluctuations and shifts the critical point relative to the comparable phenomenon of optical bistability in driven-dissipative Kerr resonators. We then demonstrate that this mechanism quantitatively captures the bistability phase boundary observed in the experiment of R. Labouvie et al. [Phys. Rev. Lett. 116, 235302 (2016)], resolving substantial discrepancies in prior modeling efforts. Our results reveal how driving, dissipation and quantum coherence can interact to induce nonequilibrium phase transitions in ultra-cold atomic gases.
Quantum Gases (cond-mat.quant-gas)
5 + 4 pages
Finite-Time Thermodynamics Perspective into Nuclear Power Plant Heat Cycle
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
Nuclear power plants are prominent examples of heat-to-work conversion systems, and optimizing their thermodynamic performance offers significant potential for enhancing energy efficiency. With a development history of less than a century, optimization trends in nuclear power plants indicate that classical thermodynamics alone may be insufficient, particularly when maximizing output power rather than efficiency becomes the primary focus. This paper re-examines nuclear power plant thermodynamic cycles through the lens of finite-time thermodynamics, an approach specifically developed to address the practical requirement of enhancing power output. Beginning with the simpler Brayton cycle without phase transitions, we obtain the famous Curzon-Ahlborn formula for efficiency at maximum power. Subsequently we analyze the more complex Rankine cycle, which incorporates phase transitions. By explicitly considering the working fluid undergoing phase transitions within the cycle, we uncover the inherent trade-off between output power and efficiency. Additionally, we demonstrate that both the maximum attainable power and efficiency increase as latent heat rises. These findings shall provide insights and methodologies for future thermodynamic optimization of nuclear power plants and other Rankine-type cycle systems.
Statistical Mechanics (cond-mat.stat-mech)
14 pages, 8 figures
Fingerprinting Organic Molecules for the Inverse Design of Two-Dimensional Hybrid Perovskites with Target Energetics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Yongxin Lyu, Yifan Zhou, Yu Zhang, Yang Yang, Bosen Zou, Qiang Weng, Tong Xie, Claudio Cazorla, Jianhua Hao, Jun Yin, Tom Wu
Artificial intelligence (AI)-assisted workflows have transformed materials discovery, enabling rapid exploration of chemical spaces of functional materials. Endowed with extraordinary optoelectronic properties, two-dimensional (2D) hybrid perovskites represent an exciting frontier, but current efforts to design 2D perovskites rely heavily on trial-and-error and expert intuition approaches, leaving most of the chemical space unexplored and compromising the design of hybrid materials with desired properties. Here, we introduce an inverse design workflow for Dion-Jacobson perovskites that is built on an invertible fingerprint representation for millions of conjugated diammonium organic spacers. By incorporating high-throughput density functional theory (DFT) calculations, interpretable machine learning, and synthesis feasibility screening, we identified new organic spacer candidates with deterministic energy level alignment between the organic and the inorganic motifs in the 2D hybrid perovskites. These results highlight the power of integrating invertible, physically meaningful molecular representations into AI-assisted design, streamlining the property-targeted design of hybrid materials.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Schwinger boson theory for $S=1$ Kitaev quantum spin liquids
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
The Kitaev model is an exactly solvable model with a quantum spin liquid ground state. While this model was originally proposed as an $ S=1/2$ spin model on a honeycomb lattice, extensions to higher-spin systems have recently attracted attention. In contrast to the $ S=1/2$ case, such higher-$ S$ models are not exactly solvable and remain poorly understood, particularly for spin excitations at finite temperatures. Here, we focus on the $ S=1$ Kitaev model, which is proposed to host bosonic quasiparticles. We investigate this model using Schwinger boson mean-field theory, introducing bosonic spinons as fractional quasiparticles by extending bond operators to address anisotropic spin interactions. We determine the mean-field parameters that realize a quantum spin liquid in both ferromagnetic and antiferromagnetic Kitaev models. Based on this ansatz, we calculate dynamical and equal-time spin structure factors. We find that the conventional scheme based on Wick decoupling with respect to spinons yields unphysical momentum dependence: it produces strong spectral weight indicating ferromagnetic (antiferromagnetic) correlations in the antiferromagnetic (ferromagnetic) Kitaev model. To resolve this issue, we propose an alternative evaluation based on decoupling with respect to bond operators. We demonstrate that, in our scheme, such unphysical behavior disappears and the momentum dependence of the spin structure factors is consistent with the sign of the exchange constant. We also compute the temperature evolution of the dynamical spin structure factor and find that the zero-temperature continuum splits into two distinct structures as temperature increases, which can be understood in terms of the bandwidth narrowing of spinons. Finally, we clarify why the two decoupling schemes result in different momentum dependences and discuss their relationship to previous studies.
Strongly Correlated Electrons (cond-mat.str-el)
17 pages, 8 figures
Discovery of oxide Li-conducting electrolytes in uncharted chemical space via topology-constrained crystal structure prediction
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Seungwoo Hwang, Jiho Lee, Seungwu Han, Youngho Kang, Sungwoo Kang
Oxide Li-conducting solid-state electrolytes (SSEs) offer excellent chemical and thermal stability but typically exhibit lower ionic conductivity than sulfides and chlorides. This motivates the search for new oxide materials with enhanced conductivity. Crystal structure prediction is a powerful approach for identifying such candidates. However, the structural complexity of oxide SSEs, often involving unit cells with more than 100 atoms, presents significant challenges for conventional methods. In this study, we introduce TOPIC, a structure prediction algorithm that reduces configurational complexity by enforcing corner-sharing (CS) bond topology constraints. We demonstrate that TOPIC successfully reproduces the ground-state and metastable structures of known oxide SSEs, including LiTa$ _2$ PO$ _8$ and Li$ _7$ La$ _3$ Zr$ _2$ O$ _{12}$ , which contain up to about 200 atoms per unit cell. By combining this approach with a pretrained machine-learning interatomic potential, we systematically screen quaternary oxide compositions and identify 92 promising candidates with CS frameworks. In particular, Li$ _4$ Hf$ _2$ Si$ _3$ O$ _{12}$ , which corresponds to the ground state at its composition, exhibits an ionic conductivity of 14 mS cm$ ^{-1}$ , a hull energy of 21 meV atom$ ^{-1}$ , and a band gap of 6.5 eV. Through our investigation, we identify the Li ratio as one of the key factors determining the stability of CS structures. Overall, our approach provides a practical and scalable pathway for discovering high-performance oxide solid electrolytes in previously unexplored chemical spaces.
Materials Science (cond-mat.mtrl-sci)
Effect of Deposition Pressure on the Superconductivity of Ti40V60 Alloy Thin Films
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Shekhar Chandra Pandey, Shilpam Sharma, R. Venkatesh, L. S. Sharath Chandra, M. K. Chattopadhyay
The growth and characterization of high quality superconducting thin films is essential for fundamental understanding and also for the use of these films in technological applications. In the present study, Ti40V60 alloy thin films have been deposited using DC magnetron co sputtering of Ti and V at ambient temperatures. The effect of deposition pressure on the film morphology, superconducting and normal state properties has been studied. Measurement of electrical resistance as a function of temperature indicates that up to a certain deposition pressure, the 20 nm thick Ti40V60 films exhibit metallic behavior in the normal state and superconductivity at low temperatures. Beyond a threshold pressure, the films show a negative temperature coefficient of resistance with a residual resistance ratio less than one. Electrical transport measurements in the presence of magnetic field were performed to find the current voltage characteristics of the thin films. Analysis of the I V curves indicates that the Ti40V60 alloy thin films have a large transport critical current density (JC) e.g. 1.475E10 A per m2 in zero magnetic field and 2.657E09 A per m2 in 4 T (both at 4 K). Analysis of the field dependence of flux line pinning force density indicates a combined effect of core delta k surface and core delta k point pinning mechanisms (where k is the Ginzburg Landau parameter). Additionally, spatial variations in the superconducting critical temperature (TC ) across the sample contribute to delta TC pinning. In higher magnetic fields, a contribution from delta l pinning (where l is the electron mean free path) also becomes significant. The findings indicate the potential of Ti40V60 alloy thin film for superconducting device applications like cryogenic radiation detectors.
Superconductivity (cond-mat.supr-con)
Preparation Methods and Applications of Biomimetic Membranes
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Ajit Seth, Sajal K. Ghosh, Veerendra K. Sharma
Model biomembrane systems play a crucial role in advancing biomedical research by providing simplified yet effective platforms for exploring complex biological mechanisms. These systems span a wide range of scales, from single-molecule-thick lipid monolayers to micron-sized giant unilamellar vesicles. Their efficacy and applicability largely depend on selecting an optimal model and an appropriate synthesis process. This chapter offers a comprehensive description of conventional synthesis techniques, highlighting their limitations across various model membrane systems. Additionally, it provides an overview of biophysical studies on biomimetic membranes and explores key biological applications, including drug delivery, membrane-protein interactions, and biosensing.
Soft Condensed Matter (cond-mat.soft)
Growth Optimization of MoSi Thin Film and Measurement of Transport Critical Current Density of its Meander Structure
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Shekhar Chandra Pandey Shilpam Sharma, M. K. Chattopadhyay
Amorphous thin film superconductors are promising alternatives for the development of superconducting radiation detectors, especially superconducting nanowire single photon detectors (SNSPDs) and superconducting microwire single photon detectors (SWSPDs), due to their homogeneous nature, ease of deposition, and superconducting parameters comparable to the materials currently being used. A study on the optimization of the growth technology and superconducting transition temperature (TC) of MoSi thin films grown on SiO2 coated Si substrate is reported here. These films have been synthesized by co sputtering of Mo and Si targets with varying compositions and thicknesses to achieve optimized TC values close to that of the bulk. Mo80Si20 and Mo83Si17 compositions of the film, each with a thickness of 17 nm, exhibited the highest TC of 6.4 K and 5.9 K, respectively. Additionally, a meander structure with a 17 um wire width was patterned to estimate the transport critical current density (JC), which was measured to be 1.4E9 A per m2 at 4 K. Variation of the TC with film thickness and deposition pressure has been studied. Electrical resistance as a function of temperature of the film before and after meandering was also studied. These properties are compatible with the fabrication of superconducting nanowire, microwire and wide strip single photon detectors.
Superconductivity (cond-mat.supr-con)
Fine-Tuning Bulk-oriented Universal Interatomic Potentials for Surfaces: Accuracy, Efficiency, and Forgetting Control
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Jaekyun Hwang, Taehun Lee, Yonghyuk Lee, Su-Hyun Yoo
Accurate prediction of surface energies and stabilities is essential for materials design, yet first-principles calculations remain computationally expensive and most existing interatomic potentials are trained only on bulk systems. Here, we demonstrate that fine-tuning foundation machine learning potentials (MLPs) significantly improves both computational efficiency and predictive accuracy for surface modeling. While existing universal interatomic potentials (UIPs) have been solely trained and validated on bulk datasets, we extend their applicability to complex and scientifically significant unary, binary, and ternary surface systems. We systematically compare models trained from scratch, zero-shot inference, conventional fine-tuning, and multi-head fine-tuning approach that enhances transferability and mitigates catastrophic forgetting. Fine-tuning consistently reduces prediction errors with orders-of-magnitude fewer training configurations, and multi-head fine-tuning delivers robust and generalizable predictions even for materials beyond the initial training domain. These findings offer practical guidance for leveraging pre-trained MLPs to accelerate surface modeling and highlight a scalable path toward data-efficient, next-generation atomic-scale simulations in computational materials science.
Materials Science (cond-mat.mtrl-sci)
Main text: 21 pages, 6 figures, Supplementary information: 10 pages, 5 figures
Superconducting gap structures in wallpaper fermion systems
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
We theoretically investigate the superconducting gap structures in wallpaper fermions, which are surface states of topological nonsymmorphic crystalline insulators, based on a two-dimensional effective model. A symmetry analysis identifies six types of momentum-independent pair potentials. One hosts a point node, two host line nodes, and the remaining three are fully gapped. By classifying the Bogoliubov–de Gennes Hamiltonian in the zero-dimensional symmetry class, we show that the point and line nodes are protected by $ \mathbb{Z}_2$ topological invariants. In addition, for the twofold-rotation-odd pair potential, nodes appear on the glide-invariant line and are protected by crystalline symmetries, as clarified by the Mackey–Bradley theorem.
Superconductivity (cond-mat.supr-con)
17 pages, 8 figures, proceedings of LT30
Kinetics of the photochromic effect in oxygen-containing rare-earth hydrides
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Dmitrii Moldarev, Tuan T. Tran, Max Wolff, Daniel Primetzhofer
The kinetics of the photochromic reaction of oxygen-containing rare-earth hydrides is commonly described by an exponential function assuming a single-step process. In this paper, we elaborate on the origin of the photochromic effect in oxygen-containing rare-earth metal hydrides, considering the kinetics of the reaction as a two-step process. We show that the fit to the experimental data is improved drastically when two processes that cause the photodarkening are assumed: a fast reaction rate-limited - for example, electronic or local - process and a slow, e.g. diffusion-limited process.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
5 pages, 4 figures
Revealing Hidden Antiparallel Domains in Hexagonal Boron Nitride
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Yeri Lee, Juseung Oh, Kyung Yeol Ma, Seung Jin Lee, Eui Young Jung, Yani Wang, Kenji Watanabe, Takashi Taniguchi, Hailin Peng, Hiroki Ago, Ki Kang Kim, Hyeon Suk Shin, Sunmin Ryu
Hexagonal boron nitride (hBN) supports a wide range of two-dimensional (2D) technologies, yet assessing its crystalline quality over large areas remains a fundamental challenge. Both antiparallel domains, an intrinsic outcome of epitaxy on high-symmetry substrates, and orientational domains have long evaded optical detection. Here, we show that interferometric second-harmonic generation (SHG) polarimetry provides a powerful, non-destructive probe of lattice orientation and structural integrity in chemical vapor deposition-grown hBN. This approach reveals the ubiquitous formation of antiparallel domains and quantifies their impact on crystalline order. SHG intensity also emerges as a direct optical metric of domain disorder, spanning three orders of magnitude across films produced by ten different growth routes. Correlation with Raman spectroscopy establishes a unified framework for evaluating crystalline quality. Beyond hBN, this method offers a high-throughput route to wide-area structural imaging in other non-centrosymmetric 2D materials, advancing their deployment in electronics, photonics, and quantum technologies.
Materials Science (cond-mat.mtrl-sci)
23 pages, 5 figures
Quaking in Soft Granular Particles with Speed-dependent Friction: Effect of Inertia
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Our previous numerical simulation [C.-E. Tsai et al., Physical Review Research 6, 023065 (2024)] has shown that, for soft granular particles under quasistatic shearing, incorporating a speed-dependent friction is a necessary condition for reproducing the rate-dependent stick-slip fluctuations that have been found in laboratory experiments [J.-C. Tsai et al., Physical Review Letters 126, 128001 (2021)]. As a continuation, here we employ the simulation at a wide range of driving speeds to examine how grain inertia could also play a role in the quaking dynamics. We identify the critical volume fraction $ \phi_{\text{c}}$ below which the system exhibits inertial flow as opposed to quasistatic flow. The quaking is found to occur only within the intermediate range of the characteristic speed ($ V_{\text{c}}$ , beyond which the inter-particle friction declines) and at volume fractions above $ \phi_{\text{c}}$ . We conclude our findings by presenting state diagrams which show the progressive narrowing of the quaking regime as the driving speed increases and the disappearance of quaking at an extremely high shear rate.
Soft Condensed Matter (cond-mat.soft)
8 pages, 7 figures
Accelerated Discovery of High-\k{appa} Oxides with Physics-Based Factorized Machine Learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Atsushi Takigawa, Shin Kiyohara, Yu Kumagai
Considerable effort continues to be devoted to the exploration of next-generation high-\k{appa} materials that combine a high dielectric constant with a wide band gap. However, machine learning (ML)-based virtual screening has remained challenging, primarily due to the low accuracy in predicting the ionic contribution to the dielectric tensor, which dominates the dielectric performance of high-\k{appa} materials. We here propose a joint ML model that predicts Born effective charges using an equivariant graph neural network, and phonon properties using a highly accurate pretrained ML potential. The ionic dielectric tensor is then computed analytically from these quantities. This approach significantly improves the accuracy of ionic contribution. Using the proposed model, we successfully identified 38 novel high-\k{appa} oxides from a screening pool of over 8,000 candidates.
Materials Science (cond-mat.mtrl-sci)
42 pages, 13 figures, 6 tables, submitted
Topological Textures in Zr-Substituted Barium Titanate
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Topological polarization textures in ferroelectrics offer pathways to dense memory, neuromorphic computing, and controlled probes of topology in solids. In rhombohedral barium titanate, theory has identified stable antiskyrmions of topological charge -2 that fractionalize into six -1/3 fractional hotspots, termed topological quarks. Here we extend this landscape to Zr-substituted barium titanate (BZT) using a first-principles parameterized effective-Hamiltonian framework. In an ordered 12.5% composition, the chemically doubled periodicity enforces an alternation along [111]: one half hosts the -2 antiskyrmion (six -1/3 quarks), the other a +4 skyrmion (six +2/3 quarks). The two share the same six-vortex skeleton but differ by an integer +1 per vortex in the plane-integrated slice charge. In random BZT, nanodomains remain inducible and cryogenically stable, yet quenched disorder pins and distorts the vortices, producing a heterogeneous, skyrmion-glass like state with fluctuations of the topological charge along the axis. Thermal stability maps show that pure BT retains -2 textures up to ~100 K, whereas in BZT the critical temperature is nonmonotonic, with a minimum near 6-8% Zr, reflecting competition between ferroelectric softening and disorder pinning. Importantly, the 12.5% ordered arrangement remains rhombohedral above 300 K, enabling field-stabilized nanodomains at 293 K. Under a local [111] bias, the ordered system carries +4 slice charge, while the random composition fragments under the same conditions. These results establish BZT as a platform for chemically programmed, fractionalized ferroelectric topology from cryogenic to room temperature and suggest routes to multistate, reconfigurable devices.
Materials Science (cond-mat.mtrl-sci)
16 pages, 4 figures, plus supplemental material
Exact heat flux formula and its spectral decomposition in molecular dynamics for arbitrary many-body potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Markos Poulos, Donatas Surblys, Konstantinos Termentzidis
In this study we have derived an exact framework for the calculation of the heat flux and its spec- tral decomposition in Molecular Dynamics (MD) for arbitrary many-body potentials. This work addresses several lacks and limitations of previous approaches and allows for the accurate computa- tional study of thermal properties in a wide variety of many-body systems with MD. We have tested our modifications with Green-Kubo (GK) and Non-Equilibrium MD (NEMD) simulations for vari- ous 2D and 3D material systems using the Tersoff and Stillinger-Weber potentials as examples. The spectral decomposition of the heat current was also calculated for monolayer graphene (1LG) and MoS2 , for different system lengths. Our results show that the heat current calculated by our method is consistently in agreement with the thermostat current in NEMD, while previous implementations can estimate quite poorly the thermal conductivity both under GK and NEMD simulations, and both for 2D and 3D materials. The decomposition of the heat current also sheds light on the con- tribution of different phonon modes to thermal conductivity and its dependence on length. Our methodology is implemented in the widely used LAMMPS code specifically for the Tersoff and SW potentials, and it is readily applicable to the vast majority of many-body MD potentials.
Materials Science (cond-mat.mtrl-sci)
Field-tuning of ultrafast magnetization fluctuations in Sm${0.7}$Er${0.3}$FeO$_{3}$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Marvin Alexander Weiss, Julius Schlegel, Daniel Anić, Emil Steiner, Franz Stefan Herbst, Makoto Nakajima, Takayuki Kurihara, Alfred Leitenstorfer, Ulrich Nowak, Sebastian T.B. Goennenwein
The properties of spin fluctuations in antiferromagnets are largely unexplored, in particular at ultrafast timescales. Here, we employ femtosecond noise correlation spectroscopy (FemNoC) to experimentally study magnetization fluctuations in the canted antiferromagnet Sm$ _{0.7}$ Er$ _{0.3}$ FeO$ _{3}$ across its spin reorientation transition and under external magnetic fields. By comparing our measurements to atomistic spin noise and Monte Carlo simulations, we find that the amplitude of the spin noise is governed by the free energy, with stronger fluctuations in regions where the potential landscape softens. We furthermore demonstrate that external magnetic fields suppress spin fluctuations and enhance the quasi-ferromagnetic magnon frequency by effectively stiffening the potential. These results highlight an effective route for tuning ultrafast magnetization fluctuations via external parameters.
Materials Science (cond-mat.mtrl-sci), Optics (physics.optics)
11 pages, 10 figures
The diffusion-driven orthorhombic to tetragonal transition in YBa$_2$Cu$_3$O$_7$ derived with a machine learning interatomic potential
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Davide Gambino, Niccolò Di Eugenio, Jesper Byggmästar, Johan Klarbring, Daniele Torsello, Flyura Djurabekova, Francesco Laviano
Defects in high temperature superconductors such as YBa$ _2$ Cu$ _3$ O$ _7$ (YBCO) critically influence their superconducting behavior, as they substantially degrade or even suppress superconductivity. With the renewed interest in cuprates for next-generation superconducting magnets operating in radiation-harsh environments such as fusion reactors and particle accelerators, accurate atomistic modeling of defects and their dynamics has become essential. Here, we present a general-purpose machine-learning interatomic potential for YBCO, based on the Atomic Cluster Expansion (ACE) method and trained on Density Functional Theory (DFT) data, with particular emphasis on defects and their diffusion mechanisms. The potential is validated against DFT calculations of ground-state properties, defect formation energies of oxygen Frenkel pairs and diffusion barriers for their formation. Remarkably, the potential captures the diffusion-driven orthorhombic to tetragonal transition at elevated temperatures, a transformation that is difficult to describe with empirical potentials, elucidating how the formation of oxygen Frenkel pairs in the basal plane governs this order-disorder transition. The ACE potential introduced here enables large-scale, predictive atomistic simulations of defect dynamics and transport processes in YBCO, providing a powerful tool to explore its stability, performance, and functionality under realistic operating conditions. Moreover, this work proves that machine learning interatomic potentials are suitable for studies of quaternary oxides with complex chemistry.
Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
30 pages, 6 figures
Self-organized adaptive branching in frangible matter
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
P.L.B. Fischer, J. Tauber, T. Koch, L. Mahadevan
Soft and frangible materials that remodel under flow can give rise to branched patterns shaped by material properties, boundary conditions, and the time scales of forcing. We present a general theoretical framework for emergent branching in these frangible (or threshold) materials that switch abruptly from resisting flow to permitting flow once local stresses exceed a threshold, relevant for ex- amples as varied as dielectric breakdown of insulators and the erosion of soft materials. Simulations in 2D and 3D show that branching is adaptive and tunable via boundary conditions and domain geometry, offering a foundation for self-organized engineering of functional transport architectures.
Soft Condensed Matter (cond-mat.soft), Adaptation and Self-Organizing Systems (nlin.AO), Fluid Dynamics (physics.flu-dyn)
Anisotropic antiferromagnetic order in EuPd$_3$Si$_2$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Michelle Ocker, Franziska Walther, Nour Maraytta, Matthieu Le Tacon, Michael Merz, Cornelius Krellner, Kristin Kliemt
Single crystals of EuPd$ 3$ Si$ 2$ were grown using a high-temperature EuPd-flux method. The material was structurally and chemically characterized by single-crystal x-ray diffraction, powder x-ray diffraction, Laue method and energy-dispersive x-ray spectroscopy. The structural analysis confirmed the orthorhombic crystal structure (space group $ Imma$ ) but revealed differences in the lattice parameters and bond distances in comparison to previous work by Sharma et al.. The composition is close to the ideal 1:3:2 stoichiometry with an occupation of 7 % of the Si sites by Pd. The heat capacity, electrical resistivity, and magnetic susceptibility show two magnetic transitions indicating antiferromagnetic ordering below $ T{\rm N1}= 61,\rm K$ and a spin reorientation at $ T{\rm N2}= 40,\rm K$ . The orthorhombic material shows magnetic anisotropy with field applied along the three main symmetry axes, which is summarized in the temperature-field phase diagrams. The susceptibility data hint to an alignment of the magnetic moments along $ [100]$ between $ T_{\rm N1}$ and $ T_{\rm N2}$ . Below $ T_{\rm N2}$ the magnetic structure changes to an arrangement with moments canted away from $ [100]$ . In contrast to published work by Sharma et al., the single crystals investigated in this study show AFM order below $ T_{\rm N1}$ instead of ferromagnetism that sets in at higher $ T_{\rm C1}=78,\rm K$ which might originate from certain differences in the structure, composition or defects that have an impact on the dominant coupling constants of the RKKY interaction.
Strongly Correlated Electrons (cond-mat.str-el)
Tracer diffusion coefficients in a sheared granular gas. Exact results
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
David González Méndez, Vicente Garzó
The diffusion of tracer particles immersed in a granular gas under uniform shear flow (USF) is analyzed within the framework of the inelastic Boltzmann equation. Two different but complementary approaches are followed to achieve exact results. First, we maintain the structure of the Boltzmann collision operator but consider inelastic Maxwell models (IMM). Using IMM allows us to compute the collisional moments of the Boltzmann operator without knowing the velocity distribution functions of the granular binary mixture explicitly. Second, we consider a kinetic model of the Boltzmann equation for inelastic hard spheres (IHS). This kinetic model is based on the equivalence between a gas of elastic hard spheres subjected to a drag force proportional to the particle velocity and a gas of IHS. We solve the Boltzmann–Lorentz kinetic equation for tracer particles using a generalized Chapman–Enskog–like expansion around the shear flow distribution. This reference distribution retains all hydrodynamic orders in the shear rate. The mass flux is obtained to first order in the deviations of the concentration, pressure, and temperature from their values in the reference state. Due to the velocity space anisotropy induced by the shear flow, the mass flux is expressed in terms of tensorial quantities rather than the conventional scalar diffusion coefficients. The exact results derived here are compared with those previously obtained for IHS by using different approximations [JSTAT P02012 (2007)]. The comparison generally shows reasonable quantitative agreement, especially for IMM results. Finally, we study segregation by thermal diffusion as an application of the theory. The phase diagrams illustrating segregation are shown and compared with IHS results, demonstrating qualitative agreement.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
25 pages; 9 figures
Computing Large Deviations of First-Passage-Time Statistics in Open Quantum Systems: Two Methods
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
We propose two methods for computing the large deviations of the first-passage-time statistics in general open quantum systems. The first method determines the region of convergence of the joint Laplace transform and the $ z$ -transform of the first-passage time distribution by solving an equation of poles with respect to the $ z$ -transform parameter. The scaled cumulant generating function is then obtained as the logarithm of the boundary values within this region. The theoretical basis lies in the facts that the dynamics of the open quantum systems can be unraveled into a piecewise deterministic process and there exists a tilted Liouville master equation in Hilbert space. The second method uses a simulation-based approach built on the wave function cloning algorithm. To validate both methods, we derive analytical expressions for the scaled cumulant generating functions in field-driven two-level and three-level systems. In addition, we present numerical results alongside cloning simulations for a field-driven system comprising two interacting two-level atoms.
Statistical Mechanics (cond-mat.stat-mech)
16 pages, 2 figures
Spin-supersolidity induced quantum criticality and magnetocaloric effect in the triangular-lattice antiferromagnet Rb$_2$Co(SeO$_3$)$_2$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Yi Cui, Zhanlong Wu, Zhongcen Sun, Kefan Du, Jun Luo, Shuo Li, Jie Yang, Jinchen Wang, Rui Zhou, Qian Chen, Yoshimitsu Kohama, Atsuhiko Miyata, Zhuo Yang, Rong Yu, Weiqiang Yu
We performed high-field magnetization, magnetocaloric effect (MCE), and NMR measurements on the Ising triangular-lattice antiferromagnet Rb$ _2$ Co(SeO$ 3$ )$ 2$ . The observations of the 1/3-magnetization plateau, the split NMR lines, and the thermal activation behaviors of the spin-lattice relaxation rate $ 1/T_1$ between 2 T and 15.8 T provide unambiguous evidence of a gapped up-up-down (UUD) magnetic ordered phase. For fields between 15.8 T and 18.5 T, the anomaly in the magnetic susceptibility, the slow saturation of the NMR line spectral ratio with temperature, and the power-law temperature dependence of $ 1/T_1$ suggest the ground state to be a spin supersolid with gapless spin excitations. With further increasing the field, the Grüneisen ratio, extracted from the MCE data, reveals a continuous quantum phase transition at $ H{\rm C}\approx$ 19.5 T and a universal quantum critical scaling with the exponents $ {\nu}z\approx$ 1. Near $ H{\rm C}$ , the large high-temperature MCE signal and the broad peaks in the NMR Knight shift and $ 1/T_1$ , manifest the strong spin fluctuations driven by both magnetic frustration and quantum criticality. These results establish Rb$ _2$ Co(SeO$ _3$ )$ _2$ as a candidate platform for cryogenic magnetocaloric cooling.
Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 5 figures
Symmetry restoration in a fast scrambling system
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Entanglement asymmetry – used here as a direct probe of symmetry restoration – provides a sharp diagnostic of post-quench dynamics. We test this idea in the complex Sachdev–Ye–Kitaev (cSYK) model with a conserved U(1) charge. Using exact diagonalization, we track the joint evolution of entanglement entropy and entanglement asymmetry after quenches from charge-asymmetric product states. We find rapid volume-law entanglement growth consistent with the subsystem eigenstate thermalization hypothesis, accompanied by a concurrent decay of entanglement asymmetry to a late-time plateau set by finite-size effects: small subsystems display near-complete restoration, while residual cross-sector weight yields a finite plateau. Notably, we uncover a quantum Mpemba effect: states prepared further from symmetry relax faster and approach lower residual asymmetry; disorder in the couplings renders this behavior more robust and monotonic across parameters. We further derive a Pinsker-type lower bound that ties the decay of asymmetry to differences in subsystem purity, identifying dephasing between U(1) charge sectors as the operative mechanism. These results establish entanglement asymmetry as a sensitive probe of symmetry restoration and thermalization, clarifying finite-size limits in fast-scrambling, closed quantum systems.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
8 pages, 6 figures, 1 table
Anderson localization: a density matrix approach
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-10-01 20:00 EDT
Ziyue Qi, Yi Zhang, Mingpu Qin, Hongming Weng, Kun Jiang
Anderson localization is a quantum phenomenon in which disorder localizes electronic wavefunctions. In this work, we propose a new approach to study Anderson localization based on the density matrix formalism. Drawing an analogy to the standard transfer matrix method, we extract the localization length from the modular density matrix in quasi-one-dimensional systems. This approach successfully captures the metal-insulator transition in the three-dimensional Anderson model and in the two-dimensional Anderson model with spin-orbit coupling. It can be also readily extended to multiorbital systems. We further generalize the formalism to interacting systems, showing that the one-dimensional spinless attractive model exhibits the expected metallic phase, consistent with previous studies. More importantly, we demonstrate the existence of a two-dimensional metallic phase in the presence of Hubbard interactions and disorder. This method offers a new perspective on Anderson localization and its interplay with interactions.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 7 figures in the main text, and 13 pages, 9 figures in the Appendix
From Shapiro steps to photon-assisted tunneling in microwave-driven atomic-scale Josephson junctions with a single (magnetic) adatom
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
Martina Trahms, Bharti Mahendru, Clemens B. Winkelmann, Katharina J. Franke
Ultra-small Josephson junctions are strongly influenced by noise and damping due to energy dissipation into the environment, which are expected to suppress phase coherence. Here, we investigate the coherence properties of atomic-scale Josephson junctions in a scanning tunneling microscope under microwave excitation. Plain Pb-Pb junctions exhibit hysteretic Shapiro steps as signature of a coherent resonant state. With increasing AC amplitude, phase coherence is reduced due to an increase of thermal fluctuations. In the presence of magnetic adatoms the Josephson coupling energy is reduced and quasi-particle tunneling is enhanced. With AC driving we observe a rapid suppression of coherence that we ascribe to photon-assisted quasi-particle tunneling through Yu-Shiba-Rusinov states. Our results highlight the presence of phase coherence and shed light on the origin of the transition to incoherent transport, thereby revealing the importance of controlling dissipation in nanoscale superconducting devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
Observation of non-Hermitian topology in cold Rydberg quantum gases
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-01 20:00 EDT
Jun Zhang, Ya-Jun Wang, Shi-Yao Shao, Bang Liu, Li-Hua Zhang, Zheng-Yuan Zhang, Xin Liu, Chao Yu, Qing Li, Han-Chao Chen, Yu Ma, Tian-Yu Han, Qi-Feng Wang, Jia-Dou Nan, Yi-Ming Yin, Dong-Yang Zhu, Qiao-Qiao Fang, Dong-Sheng Ding, Bao-Sen Shi
The pursuit of topological phenomena in non-Hermitian systems has unveiled new physics beyond the conventional Hermitian paradigm, yet their realization in interacting many-body platforms remains a critical challenge. Exploring this interplay is essential to understand how strong interactions and dissipation collectively shape topological phases in open quantum systems. Here, we experimentally demonstrate non-Hermitian spectra topology in a dissipative Rydberg atomic gas and characterize parameters-dependent winding numbers. By increasing the interaction strength, the system evolves from Hermitian to non-Hermitian regime, accompanying emergence of trajectory loop in the complex energy plane. As the scanning time is varied, the spectra topology becomes twisted in the complex energy plane manifesting as a topology phase transition with the sign winding number changed. When preparing the system in different initial states, we can access a nontrivial fractional phase within a parameter space that globally possesses an integer winding. Furthermore, by changing the scanning direction, we observe the differentiated loops, revealing the breaking of chirality symmetry. This work establishes cold Rydberg gases as a versatile platform for exploring the rich interplay between non-Hermitian topology, strong interactions, and dissipative quantum dynamics.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
Why is topology hard to learn?
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
D. O. Oriekhov, Stan Bergkamp, Guliuxin Jin, Juan Daniel Torres Luna, Badr Zouggari, Sibren van der Meer, Naoual El Yazidi, Eliska Greplova
Much attention has been devoted to the use of machine learning to approximate physical concepts. Yet, due to challenges in interpretability of machine learning techniques, the question of what physics machine learning models are able to learn remains open. Here we bridge the concept a physical quantity and its machine learning approximation in the context of the original application of neural networks in physics: topological phase classification. We construct a hybrid tensor-neural network object that exactly expresses real space topological invariant and rigorously assess its trainability and generalization. Specifically, we benchmark the accuracy and trainability of a tensor-neural network to multiple types of neural networks, thus exemplifying the differences in trainability and representational power. Our work highlights the challenges in learning topological invariants and constitutes a stepping stone towards more accurate and better generalizable machine learning representations in condensed matter physics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn), Machine Learning (cs.LG)
5+8 pages, 4+7 figures
Néel vector and Rashba SOC effects on RKKY interaction in 2D $d$-wave altermagnets
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
Hou-Jian Duan, Miao-Sheng Fang, Ming-Xun Deng, Ruiqiang Wang
Altermagnets possess two key features: non-relativistic alternating spin splitting (i.e., altermagnetism) and a material-dependent Néel vector. The former naturally coexists with Rashba spin-orbit coupling (SOC) in real materials on substrates, prompting the question of how SOC affects the magnetic properties of altermagnets. The latter is crucial for information storage, making it essential to determine its orientation. To address these issues, we study the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in two-dimensional (2D) $ d$ -wave altermagnets by independently varying the Néel vector orientation and the SOC strength. Our results demonstrate that the Néel vector orientation can be accurately determined via the Ising term without SOC, or qualitatively inferred via the DM terms with SOC. Moreover, we observe a novel Dzyaloshinskii-Moriya (DM) component distinct from previous reports, whose emergence is attributed to the synergy between altermagnetism and SOC. Additionally, through tuning SOC strength, we reveal the evolution of the RKKY spin models governed by five distinct mechanisms: the spin model may be determined solely by altermagnetism, solely by SOC, or solely by the kinetic term; alternatively, altermagnetism may coincidentally yield the same moderately anisotropic spin model as SOC, or compete with SOC to produce a spin model with maximal anisotropy. Beyond SOC strength, which mechanism operates also relies on the Néel vector orientation and impurity configurations. All results are numerically verified. These findings – which were inaccessible in prior studies due to the limitations of first-order SOC expansion and fixed Néel vector orientation – provide important new insights into the magnetic properties of altermagnets.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Towards stable metal inorganic-organic complex glasses
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Tianzhao Xu, Zhencai Li, Kai Zheng, Hanmeng Zhang, Kenji Shinozaki, Huotian Zhang, Lars R. Jensen, Feng Gao, Jinjun Ren, Yanfei Zhang, Yuanzheng Yue
Metal inorganic-organic complex (MIOC) glasses have emerged as a new family of melt-quenched glasses. However, the vitrification of MIOC is challenging since most of the crystalline MIOC precursors decompose before melting. The decomposition problem severely narrows the compositional range of MIOC glass formation. Here, we report a novel approach for preparing the MIOC glasses that combines slow-solvent-removal with subsequent quenching to avoid gel thermal decomposition and crystallization. Specifically, the new approach utilizes an aprotic solvent (acetone) to kinetically prevent the ordering of the metal-ligand complex molecules in solution, thereby suppressing crystallization and forming a gel. The subsequent gradual drying process leads to the removal of the solvent to enhance the connections between molecules through hydrogen bonds, thus causing the formation of a hydrogen-bonded network. The increased network connectivity lowers the mobility of the molecules, thereby avoiding gel crystallization. Consequently, a disordered network is frozen-in during quenching of the dried gel from 130 °C to room temperature, and finally MIOC glass forms. Structural analyses reveal that hydrogen bonds are responsible for connecting the tetrahedral units. The as-prepared MIOC glass exhibits some fascinating behaviors, e.g., Tg increasing with rapid room-temperature relaxation, CO2 uptake, and red-shift of photoluminescence. This work not only presents a novel strategy for fabricating large-sized, stable, functional MIOC glasses, but also uncovers the critical role of hydrogen bonds in MIOC glass formation.
Materials Science (cond-mat.mtrl-sci)
Stochastic Path Integral for the Active Brownian Particle in a Harmonic Potential
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Carsten Littek, Mike Brandt, Falko Ziebert
In this work we develop and apply a path integral formulation for the microscopic degrees of freedom obeying stochastic differential equations to an active Brownian particle (ABP) trapped in a harmonic potential. The formalism allows to derive exact analytic expressions for the time-dependent moments, like the mean position and the mean square displacement, including full dependence on initial conditions. In addition, the probability distribution of the particle’s position can be evaluated systematically as a series expansion in the propulsion speed. Compared to previous methods relying on eigenfunction expansions of the equivalent Fokker-Planck equation, our method is easier to generalize to more complex situations: it does not rely on eigenfunctions but on a reference state that can be solved analytically, which in our case is the passive Brownian particle in a harmonic potential. We exemplify this versatility by also briefly treating an ABP with an active torque (Brownian circle swimmer, BCS) in a harmonic potential.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
27 pages, 4 figures
MoSe2 and WSe2 shell morphology control via temperature optimization during two-step growth of ZnSe-based core-shell nanowires
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Luize Dipane, Liora Kotlara, Viktors Vibornijs, Katrina Laganovska, Aleksejs Zolotarjovs, Eriks Dipans, Jevgenijs Gabrusenoks, Boris Polyakov, Edgars Butanovs
Achieving uniform and controlled transition metal dichalcogenide (TMD) shell growth on nanowires (NWs) remains a key challenge, limiting the development of high-quality core-shell heterostructures for optoelectronic and photocatalytic applications. In this work, the fabrication of ZnSe-MoSe2 and ZnSe-WSe2 core-shell NWs was successfully demonstrated. ZnSe NWs were grown via the vapor-liquid-solid growth mechanism, while TMD (MoSe2 or WSe2) shells were formed through a two-step process of sacrificial oxide layer deposition via magnetron sputtering followed by selenization process in a chemical vapor transport reactor. As-grown nanostructures were characterized using X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and photoluminescence spectroscopy. It was observed that the TMD shell morphology can be controlled through the selenization process temperature optimization, which arises due to different growth mechanisms discussed here. The studied trends could be further extended to other semiconductor NW and TMD core-shell heterostructure growth, offering promising avenues for advanced nanoscale applications.
Materials Science (cond-mat.mtrl-sci)
Opt. Mater. 167, 117360 (2025)
Classical Heisenberg and XY models on zigzag ladder lattices with nearest-neighbor bilinear-biquadratic exchange: Exact solution for the ground-state problem
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
An exact and complete solution of the ground-state problem for the classical Heisenberg and XY models with nearest-neighbor bilinear-biquadratic exchange on two- and three-dimensional lattices composed of isosceles triangles is determined with the use of a cluster method. It is shown how the geometric frustration due to the presence of triangles as structural units leads to the emergence of a rich phase diagram with incommensurate spiral orderings and their collinear limits, as well as canted and noncoplanar (conical) structures. Surprisingly, there are two different spiral phases with both continuous and discontinuous phase transitions between them. One of these phases is degenerate on two-dimensional partially anisotropic triangular lattice. This degeneracy is lifted on three-dimensional lattices. Canted phase is highly degenerate and this degeneracy persists on three-dimensional lattices.
Statistical Mechanics (cond-mat.stat-mech), Materials Science (cond-mat.mtrl-sci)
11 pages, one table, 12 figures
Magnetic phase transitions protected by topological quantum geometry transitions: effects of electron-electron interactions in the Creutz ladder system
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Abdiel de Jesús Espinosa-Champo, Gerardo G. Naumis
The interplay between electronic correlations and band topology is a central theme in modern condensed matter physics. In this work, we investigate the effects of on-site Hubbard interactions on the topological, magnetic, and quantum geometric properties of the Creutz ladder, a paradigmatic model of a one-dimensional topological insulator. Using a self-consistent mean-field approach, we uncover a first-order, interaction-driven phase transition that is simultaneously magnetic and topological. We demonstrate that as the Hubbard interaction $ U$ is increased, the system’s ground state abruptly switches from an anti-ferromagnetic (AF) configuration to a ferromagnetic (F) one. This magnetic transition coincides with a topological transition, marked by a quantized jump in the Zak phase from $ \pm\pi$ to $ 0$ . We systematically compute the phase diagrams in the parameter space of on-site energy staggering ($ \epsilon$ ) and inter-chain hopping asymmetry ($ \lambda$ ), revealing the critical interaction strength $ U_c$ . Furthermore, we analyze the quantum geometry of the Bloch states by calculating the Fubini-Study metric, demonstrating that its components exhibit divergences that precisely signal the topological phase transition. By analyzing the full energy spectrum, we distinguish the true ground state from metastable excited states that emerge past the critical point. Our results establish the Creutz-Hubbard ladder as a minimal model for studying interaction-induced topological phenomena and suggest a potential route for controlling magnetic, topological, and geometric properties via electronic correlations.
Strongly Correlated Electrons (cond-mat.str-el)
Windmilling clusters of active quadrupoles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Margaret Rosenberg, Hartmut Löwen
Active matter has thrived in recent years, driven both by the insight that it underlies fundamental processes in nature, and by its vast potential for applications. This allows for innovation both inspired by experimental observations, and by construction of novel systems with desired properties. In this paper, we develop a novel system in the search for a new kind of pattern formation: microstructural motifs with orthogonal alignment. Taking a simple active Brownian particle (ABP) model applied to dumbbell-shaped particles, we add a quadrupolar interaction by positioning two antiparallel magnetic dipolar moments on each particle. We find that the phase behavior is determined by the competition between active motion and the orthogonal alignment favored by quadrupolar attraction. By varying these quantities, we are able to tune both the internal structure of the aggregates, and find a surprising stability of triangular aggregates, to the point of clusters of size $ N=3$ being strongly overrepresented. Although none of the component particles are chiral, the resulting structures spin in a random, fixed direction due to combination of the polarity of the active motion. This results in an ensemble of windmilling (randomly spinning in a circular motion) aggregates with windmill-like shape (due to the three- or four core component dumbbells). Ultimately, this simple model shows an interesting range of microstructural motifs, with great potential for experimental implementations.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
8 pages, 9 figures
Efficient heat-energy conversion from a non-thermal Tomonaga-Luttinger liquid
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
Hikaru Yamazaki, Masashi Uemura, Haruhi Tanaka, Tokuro Hata, Chaojing Lin, Takafumi Akiho, Koji Muraki, Toshimasa Fujisawa
Energy harvesting is a technique that generates useful work from waste heat. Conventional energy harvesters acting on local thermal equilibrium states are constrained by thermodynamic limits, such as the Carnot efficiency. Quantum heat engines with non-thermal reservoirs are expected to exceed such limits. Here, we demonstrate energy harvesting from a nonthermal Tomonaga-Luttinger (TL) liquid in quantum Hall edge channels, where the non-thermal state is naturally formed due to the absence of thermalization. The scheme is tested with a quantum-dot energy harvester working on a non-thermal TL liquid supplied with waste heat from a quantum-point-contact transistor. Compared to the quasi-thermalized TL liquid, the non-thermal state prepared under the same heat is capable of a larger electromotive force and higher conversion efficiency. These characteristics can be understood by considering a binary Fermi distribution function of the non-thermal state induced by entropy-conserving equilibration. TL liquids are attractive non-thermal carriers for excellent energy harvesting.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
15 pages, 11 figures
Commun. Phys. 8, 387 (2025)
Strain-Gradient-Driven Decoupling of Thermal Suppression from Anisotropy in \b{eta}-Ga2O3
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Guangwu Zhang, Xing Xiang, Ziyan Qian, Yixin Xu, Shengying Yue, Hyejin Jang, Lin Yang, Yanguang Zhou, Xinyu Wang, Qiye Zheng
Strain gradients, ubiquitous in flexible devices and epitaxial nanostructures, are a major blind spot for thermal transport in \b{eta}-Ga2O3. We establish that strain gradient unlocks a thermal conductivity (k) suppression mechanism fundamentally more potent than uniform strain: moderate uniaxial gradients (0.6%/nm) suppress k by 32-37% (27-30%) in thin films (nanowires), intensifying to 43.3% with biaxial gradients. This reduction far exceeds that from equivalent uniform strain and surpasses benchmark materials like silicon and BAs. Critically, a surprising decoupling emerges: while 3% uniform strain alters thermal anisotropy by ~25%, strain gradient strongly suppresses k with preserving this ratio. Mechanistically, strain gradients-induced symmetry breaking and enhanced mode coupling anisotropically activate forbidden scattering channels, making gradient-driven scattering dominant over intrinsic phonon scattering below 6.25 THz. These findings redefine non-uniform strain from a parasitic flaw into a powerful design tool for engineering thermal isolation and heat flux in next-generation flexible and high-power \b{eta}-Ga2O3 electronics.
Materials Science (cond-mat.mtrl-sci), Atomic Physics (physics.atom-ph)
Non-local edge mode hybridization in the long-range interacting Kitaev chain
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
David Haink, Andreas A. Buchheit, Benedikt Fauseweh
In one-dimensional p-wave superconductors with short-range interactions, topologically protected Majorana modes emerge, whose mass decays exponentially with system size, as first shown by Kitaev. In this work, we extend this prototypical model by including power law long-range interactions within a self-consistent framework, leading to the self-consistent long-range Kitaev chain (seco-LRKC). In this model, the gap matrix acquires a rich structure where short-range superconducting correlations coexist with long-range correlations that are exponentially localized at both chain edges simultaneously. As a direct consequence, the topological edge modes hybridize even if their wavefunction overlap vanishes, and the edge mode mass inherits the asymptotic scaling of the interaction. In contrast to models with imposed power law pairing, where massive Dirac modes emerge for exponents $ \nu < d$ , we analytically motivate and numerically demonstrate that, in the fully self-consistent model, algebraic edge mode decay with system size persists for all interaction exponents $ \nu > 0$ , despite exponential wave function localization. While the edge mode remains massless in the thermodynamic limit, finite-size corrections can be experimentally relevant in mesoscopic systems with effective long-range interactions that decay sufficiently slowly.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
8 pages, 2 figures
Structural and Compositional Complexities of Hierarchical Self-Assembly: a Hypergraph Approach
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Programmable self-assembly enables the construction of complex molecular, supramolecular, and crystalline architectures from well-designed building blocks. Here we introduce a hypergraph-based framework, termed Blocks & Bonds (B&B), that extends classical chemical graph theory to encode directed multi-colored interactions, internal symmetries of building blocs, and hierarchical organization. Within this framework, we develop a universal script, Structure Code, for encoding complex hypergraph organization. In the spirit of Kolmogorov’s approach, we define Structural Complexity as the minimal information required to encode a self-assembled structure. It is complemented by Compositional Complexity, capturing the diversity of building blocks. The two measures are related through Complexity Inequality, stating that structural complexity cannot exceed compositional complexity for programmable assembly, and identify cases where violations signal emergent complexity. Applications to molecular systems (ethylene glycol, glucose) and programmable DNA-origami lattices demonstrate how B&B hypergraphs and the structure code naturally capture modularity, stereochemistry, and crystallographic order while enabling significant compression of structural information. This approach provides a unified and scalable language for classifying complexity across scales, bridging information theory with the design of programmable matter.
Soft Condensed Matter (cond-mat.soft), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Mathematical Physics (math-ph)
7 pages, 2 figures
Closures of moment expansion of anisotropic active Brownian particles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Timothée Gautry, Maxime Deforet, Pierre Illien
We study analytically the dynamics of anisotropic active Brownian particles (ABPs), and more precisely their intermediate scattering function (ISF). To this end, we develop a systematic closure scheme for the moment expansion of their Fokker-Planck equation. Starting from the coupled evolution of translational and orientational degrees of freedom, we derive equations for the density, polarization, and nematic tensor fields, which naturally generate an infinite hierarchy of higher-order moments. To obtain explicit solutions, we investigate truncation strategies and analyze closures at different orders. While the closure at lowest order yields Gaussian dynamics with an effective translational diffusion, closures at higher orders incorporate orientational correlations and reproduce non-Gaussian features in the ISF. By confronting these approximations with exact solutions based on spheroidal wave functions and with Brownian dynamics simulations, we identify their range of validity in terms of Péclet number, wavenumber, and observation timescales. An advantage of this method is its ability to yield approximate yet explicit expressions not only for the ISF but also for polarization and nematic fields, which are often neglected but relevant in scattering experiments and theoretical modeling. Beyond providing a practical guide to select the appropriate closure according to the spatiotemporal regime, our framework highlights the efficiency of moment-based approaches compared to exact yet implicit formulations. This strategy can be systematically extended to more complex situations, such as propulsion switching, confinement, or external fields, where functional bases for exact solutions are generally unavailable.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
Half-filled metal and molecular-orbital-mediated pairing in cuprate
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Sixuan Chen, Zhiheng Yao, Ning Xia, Shusen Ye, Hongrui Zhang, Jianfa Zhao, Qingqing Liu, Changqing Jin, Shuo Yang, Yayu Wang
The cuprates exhibit anomalous momentum-space structure with antinodal gap and nodal arc in the underdoped regime, which evolves into a complete hole-type Fermi surface with a large Luttinger volume in the overdoped regime. The real-space electronic structure is also quite complex, as characterized by microscopic inhomogeneities and intertwined density wave orders. Here we show that doped holes in cuprate form localized electronic molecules consisting of 4a0 plaquettes, and each plaquette contains approximately two holes. The effective local doping level is thus around 1/8, which is sufficient to destroy the underlying AF order and more importantly, recovers the half-filled metallic state of the original CuO2 plane. The restored Fermi surface, hosting one hole per unit cell, is consistent with experimental results and satisfies the Luttinger theorem. We then construct the momentum-space structure of the half-filled metal by considering the real-space configuration of electronic molecules. We show that the electronic potential with 4a0 periodicity imposed by the plaquettes and the quantum size effect of electronic molecules obliterate the nested antinodal Fermi surface sheets, leaving behind short arcs with coherent quasiparticles around the node. We propose that two doped holes in each plaquette occupy the shared molecular orbital and form a spin singlet, which can mediate the pairing of itinerant holes on the remnant Fermi surface of the half-filled metal. The electric dipole moment between the molecular orbitals and the dopant ions may also provide a novel attractive interaction between itinerant holes. This phenomenological model for pair formation between itinerant holes on the half-filled Fermi surface mediated by localized molecular orbitals resolves several core issues concerning the mechanism of superconductivity in cuprates.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 4 figures
YbCu$_{1.14}$Se$_2$: an exchange disordered 2D triangular random singlet phase?
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Caitlin S. Kengle, Sean M. Thomas, Roman Movshovich, Shengzhi Zhang, Eun Sang Choi, Minseong Lee, Priscila F. S. Rosa, Allen O. Scheie
Quantum spin liquid (QSL) phases exist in theory, but real candidate QSL materials are often extraordinarily sensitive to structural defects which disrupt the ground state. Here, we investigate candidate triangular QSL material YbCu$ _{1.14}$ Se$ _2$ and discover the absence of magnetic order, but also no compelling evidence of a QSL ground state due to significant structural disorder. We instead look at the results through a lens of a 2-dimensional (2D) random singlet phase. YbCu$ _{1.14}$ Se$ _2$ behaves strikingly similar to other disordered triangular lattice materials, suggesting universal behavior of random singlet formation in 2D frustrated systems.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
LA-UR-25-29531
Peculiarities of spin dynamics excitation by magnetic field of a high-frequency electromagnetic pulse
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Nika Gribova, Anatoly Zvezdin, Vladimir Belotelov
Terahertz (THz) electromagnetic pulses offer a promising route for the ultrafast manipulation of magnetization in ferromagnetic materials. While previous studies have demonstrated the excitation of spin dynamics using linearly polarized THz fields, the role of circular polarization and the effects of rapidly oscillating, time-dependent field profiles remained insufficiently understood. We have developed a unified theoretical framework for describing the excitation of spin precession via Zeeman interaction in magnetic materials by high frequency pulses of arbitrary polarization with temporal Gaussian profile. In the regime of long pulses (at least several oscillations are within the pulse duration), a circularly polarized magnetic field acts as an effective rectified magnetic field along the pulse propagation, while linear polarized pulses excite no free precession. In the regime of short pulses (less than one oscillation is within the pulse duration), pulses of any polarization, including linear one can excite free spin precession. There is an optimal pulse duration which maximizes amplitude of the spin precession. It depends on magnetic parameters of the sample and the external magnetic field, as well as on the carrier frequency of the pulse and its amplitude. These findings bridge key gaps in the understanding of THz-induced spin dynamics and provide insights into the design of light-controlled magnetization schemes using tailored electromagnetic pulses.
Materials Science (cond-mat.mtrl-sci)
Automated and Scalable SEM Image Analysis of Perovskite Solar Cell Materials via a Deep Segmentation Framework
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Jian Guo Pan, Lin Wang, Xia Cai
Scanning Electron Microscopy (SEM) is indispensable for characterizing the microstructure of thin films during perovskite solar cell fabrication. Accurate identification and quantification of lead iodide and perovskite phases are critical because residual lead iodide strongly influences crystallization pathways and defect formation, while the morphology of perovskite grains governs carrier transport and device stability. Yet current SEM image analysis is still largely manual, limiting throughput and consistency. Here, we present an automated deep learning-based framework for SEM image segmentation that enables precise and efficient identification of lead iodide, perovskite and defect domains across diverse morphologies. Built upon an improved YOLOv8x architecture, our model named PerovSegNet incorporates two novel modules: (i) Adaptive Shuffle Dilated Convolution Block, which enhances multi-scale and fine-grained feature extraction through group convolutions and channel mixing; and (ii) Separable Adaptive Downsampling module, which jointly preserves fine-scale textures and large-scale structures for more robust boundary recognition. Trained on an augmented dataset of 10,994 SEM images, PerovSegNet achieves a mean Average Precision of 87.25% with 265.4 Giga Floating Point Operations, outperforming the baseline YOLOv8x-seg by 4.08%, while reducing model size and computational load by 24.43% and 25.22%, respectively. Beyond segmentation, the framework provides quantitative grain-level metrics, such as lead iodide/perovskite area and count, which can serve as reliable indicators of crystallization efficiency and microstructural quality. These capabilities establish PerovSegNet as a scalable tool for real-time process monitoring and data-driven optimization of perovskite thin-film this http URL source code is available at:this https URL.
Materials Science (cond-mat.mtrl-sci), Computer Vision and Pattern Recognition (cs.CV)
Memristor-Driven Spike Encoding for Fully Implantable Cochlear Implants
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-01 20:00 EDT
Tímea Nóra Török, Roland Kövecs, Ferenc Braun, Zsigmond Pollner, Tamás Zeffer, Nguyen Quoc Khánh, László Pósa, Péter Révész, Heungsoo Kim, Alberto Piqué, András Halbritter, János Volk
Neurodynamic behavior of artificial neuron circuits made of Mott memristors provides versatile opportunities to utilize them for artificial sensing. Their small size and energy efficiency of generating spiking electrical signals enable usage in fully implantable cochlear implants. Here, we propose an auditory sensing unit realized by a piezo-MEMS (micro-electromechanical systems) cantilever connected to a VO$ _2$ nanogap Mott memristor-based oscillator circuit. This auditory sensing unit is capable of frequency-selective detection of vibrations and subsequent emission of a neural spiking waveform. The auditory sensing unit is tested under biologically realistic vibration amplitudes, and spike rate-encoding of the incoming stimulus is demonstrated, similarly to natural hearing processes. The tunability of the output spiking frequency and the shape of the spiking waveform are also demonstrated to provide suitable voltage spikes for the nervous system.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Biological Physics (physics.bio-ph), Medical Physics (physics.med-ph)
8 pages, 8 figures
Molecular dynamics insights into the Debye process of 1-propanol
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-01 20:00 EDT
Marceau Hénot, Jan Philipp Gabriel
The dielectric response of mono-alcohols exhibits a strong Debye peak generally attributed to the dynamics of hydrogen-bonds (HB) supramolecular structures through a mechanism that remains unclear in many aspects. In this letter, we use standard all-atom molecular dynamics simulations to investigate this phenomenon in 1-propanol, a prototypic monoalcohol, over a wide temperature range covering a significant change in dielectric permittivity. We obtained dielectric spectra showing a Debye peak in good agreement with experimental data, which we decomposed into the self and cross parts of the dipolar correlations. The latter extends over a few molecular distances and contributes increasingly to the Debye peak upon cooling. To investigate its physical origin, we analyzed the HB structures by identifying clusters from simulation snapshots. Below 300~K, the dielectric permittivity was shown to arise almost entirely from intra-cluster cross-correlations. Furthermore, by tracking the dipole decorrelation of groups of molecules initially belonging to the same cluster, we found that supramolecular structures play a key role in stabilizing cross-correlation over time scales longer than the relaxation of individual molecules.
Soft Condensed Matter (cond-mat.soft)
7 pages, 5 figures
Orbital altermagnetism on the kagome lattice and possible application to $A$V$_3$Sb$_5$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Anzumaan R. Chakraborty, Fan Yang, Turan Birol, Rafael M. Fernandes
Altermagnets, which encompass a broad landscape of materials, are compensated collinear magnetic phases in which the antiparallel magnetic moments are related by a crystalline rotation. Here, we argue that collinear altermagnetic-like states can also be realized in lattices with an odd number of sublattices, provided that the electronic interactions promote non-uniform magnetic moments. We demonstrate this idea for a kagome metal whose band filling places the Fermi level close to the van Hove singularity. Combining phenomenological and microscopic modeling, we show that the intertwined charge density-wave and loop-current instabilities of this model lead to a wide parameter range in which orbital ferromagnetic, antiferromagnetic, and altermagnetic phases emerge inside the charge-ordered state. In the presence of spin-orbit coupling, their electronic structures display the usual spin-split fingerprints associated with the three types of collinear magnetic order. We discuss the possible realization of orbital altermagnetic phases in the $ A$ V$ _3$ Sb$ _5$ family of kagome metals.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
8 pages, 3 figures
Projected Holstein-Primakoff boson representation of quantum spins for spin wave theory
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
The Holstein-Primakoff boson representation of quantum spins and associated large-$ S$ expansion have been the standard framework for describing the spin wave excitations in magnetically order phases of quantum spin systems. However, we will show that the omission of projection operators and normal-ordering in this representation can produce incorrect magnon hamiltonians for finite $ S$ . We will present the exact normal-ordered forms of the finite-$ S$ projection operators and projected Holstein-Primakoff boson representations of spin and quadrupole operators, which can produce exact two-magnon interaction terms under ferromagnetic or fully polarized states. We will also discuss the difficulties of applying this projected representation to antiferromagnetic spin wave theory.
Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 2 figures, 1 table
Comparative study of Wavelet transform and Fourier domain filtering for medical image denoising
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-01 20:00 EDT
M. Ali Saif, Bassam M. Mughalles, Ibrahim G. H. Loqman
Denoising of images is a crucial preprocessing step in medical imaging, essential for improving diagnostic clarity. While deep learning methods offer state-of-the-art performance, their computational complexity and data requirements can be prohibitive. In this study we present a comprehensive comparative analysis of two classical, computationally efficient transform-domain techniques: Discrete Wavelet Transform (DWT) and Discrete Fourier Cosine Transform (DFCT) filtering. We evaluated their efficacy in denoising medical images which corrupted by Gaussian, Uniform, Poisson, and Salt-and-Pepper noise. Contrary to the common hypothesis favoring wavelets for their multi-resolution capabilities, our results demonstrate that a block-based DFCT approach consistently and significantly outperforms a global DWT approach across all noise types and performance metrics (SNR, PSNR, IM). We attribute DFCT’s superior performance to its localized processing strategy, which better preserves fine details by operating on small image blocks, effectively adapting to local statistics without introducing global artifacts. This finding underscores the importance of algorithmic selection based on processing methodology, not just transform properties, and positions DFCT as a highly effective and efficient denoising tool for practical medical imaging applications.
Statistical Mechanics (cond-mat.stat-mech)
21 pages, 11 figures
Non-Hermitian comb effect in coupled clean and quasiperiodic chains
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-01 20:00 EDT
Soumya Ranjan Padhi, Souvik Roy, Biswajit Paul, Sanchayan Banerjee, Tapan Mishra
We study localization properties in a system of non-Hermitian quasiperiodic chain coupled to a uniform chain or clean chain by inter-chain hopping. We find that in the limit of weak inter-chain coupling, such a coupled system exhibits transitions from delocalized to intermediate phase with increase in the non-Hermiticity parameter. However, for stronger inter-chain coupling strengths, the delocalized phase undergoes a transition to localized phase and then to an intermediate phase. Interestingly, the intermediate phase in this case exhibits the non-Hermitian comb effect (NHCE), i.e., the coexistence of localized and extended states rather than being well separated from each other by any mobility edge which is conventional in any intermediate phase. We further show that such a NHCE originates from the isolated site limit of the quasiperiodic chain and provide an analytical explanation supporting the numerical signatures.
Quantum Gases (cond-mat.quant-gas), Other Condensed Matter (cond-mat.other), Quantum Physics (quant-ph)
7 pages, 7 figures
Amplified response of cavity-coupled quantum-critical systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-01 20:00 EDT
Shouvik Sur, Yiming Wang, Mounica Mahankali, Silke Paschen, Qimiao Si
A quantum critical point develops when matter undergoes a continuous transformation between distinct ground states at absolute zero. It hosts pronounced quantum fluctuations, which render the system highly susceptible to external perturbations. While light-matter coupling has rapidly moved forward as a means to probe and control quantum materials, the capacity of quantum critical fluctuations in the photon-mediated responses has been largely unexplored. Here we advance the notion that directly coupling a quantum critical mode to a quantized cavity field dramatically facilitates the onset of superradiance. When the coupling between the two fields is bilinear, the transition is found to occur at vanishingly small light-matter coupling and is accompanied by strongly enhanced intrinsic squeezing. Our results identify a particularly favorable setting for realizing the elusive superradiant state, and point to a general principle by which quantum criticality amplifies photon-matter entanglement and enhances the associated metrological performance.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
20+11 pages, 3+3 figures
Effect of Mixed Ratios of Mangosteen Peel (Garcinia mangostana L.) and Grass Jelly Leaf (Cyclea barbata L. Miers) Natural Dyes on the Performance of Dye-Sensitized Solar Cells (DSSC)
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-01 20:00 EDT
Eka Nurfani, Haifa Salsabila, Dwiky I. Bakhtiar, Wahyu S. Sipahutar, M Alvien Ghifari, Rishal Asri, Meqorry Yusfi, Tarmizi Taher, Aditya Rianjanu, Robi Kurniawan
Dye-sensitized solar cells (DSSCs) are promising low-cost and environmentally friendly photovoltaic devices, especially when utilizing natural sensitizers. This study explores the effect of concentration ratios of natural dyes extracted from mangosteen peel (MP) and grass jelly leaves (GJL) on the optical, morphological, and photovoltaic properties of DSSCs. Dye solutions were prepared at a fixed concentration of 0.6 g/mL, with the MP:GJL volume ratio varied at 3:1, 2:1, 1:1, 1:2, and 1:3. As a result, UV-Vis absorption spectra showed that the MP contributes to the UV-blue region (350-450), while the GJL contributes to the red region (650-700 nm). The current-voltage (J-V) analysis showed that the power conversion efficiency (PCE) of MP and GJL dyes is 2.75% and 2.12%. The composite dye with a 1:3 (MP:GJL) ratio yielded the highest PCE of 3.50%, demonstrating the synergistic effect of combining these natural sensitizers to broaden the light absorption spectrum.
Materials Science (cond-mat.mtrl-sci)
Intrinsic Nernst Effect from Berry Curvature in Superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-01 20:00 EDT
Tzu-Chi Hsieh, Cong Xiao, Yi-Ting Hsu
The Nernst effect in superconductors is typically linked to fluctuating Cooper pairs above $ T_c$ or vortex motion below $ T_c$ . We show instead that Berry curvature of Bogoliubov quasiparticles can generate an intrinsic Nernst response in a clean, vortex-free superconducting state. Focusing on two-dimensional (2D) systems with Ising spin-orbit coupling, relevant to transition-metal dichalcogenides, we identify two regimes: an intervalley $ s$ -wave paired state where a weak magnetic field activates the effect, and an intravalley chiral $ p$ -wave paired state that exhibits a spontaneous charge or spin Nernst response without a field. We propose an experimental setup that circumvents screening and provide estimates of the signal magnitude. Our results establish the Nernst effect as a direct probe of Berry curvature and pairing symmetry in 2D spin-orbit-coupled superconductors.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages; 3 figures