CMP Journal 2026-09-23
Statistics
Nature: 28
Nature Materials: 2
Nature Physics: 2
arXiv: 83
Research Square: 2
Nature
Chiral oxazolidinones via biocatalytic aziridination of unactivated alkenes
Original Paper | Biocatalysis | 2026-09-22 20:00 EDT
Zi-Qi Li, Deirdre Hanley, Yu Zhang, Pei-Pei Xie, Sophia J. Wu, Zi-Yang Qin, Chi Zhang, Edwin Alfonzo, Francesca-Zhoufan Li, Sabine Brinkman-Chen, Peng Liu, Frances H. Arnold
Chiral oxazolidinones are privileged heterocycles broadly used in asymmetric synthesis (1) and drug discovery (2-3). Conventional synthetic routes rely on a “chiral pool” strategy, where enantiopure amino alcohols are required as key intermediates. Of particular importance are a class of 5-(S)-aminomethyl oxazolidinones that are key scaffolds in next-generation antibiotics targeting multidrug- and extensively drug-resistant Mycobacterium tuberculosis (4-6). While many strategies exist to construct chirality at the 4-position (α-to-nitrogen), methods to install the desired 5-stereocentre (α-to-oxygen) remain underdeveloped. Here we report a haemprotein-catalysed aziridination/ring-expansion cascade that enables direct, enantioselective synthesis of clinically relevant and discovery-stage oxazolidinones from simple alkenes. This work advances haemprotein-catalysed nitrene transfer by enabling functionalisation of unactivated alkenes, a reactivity previously limited to conjugated systems such as styrenes. Computational analysis further reveals that key mutations introduced through directed evolution are responsible for the enantioselective formation of these products.
Biocatalysis, Biosynthesis
The gene-regulatory evolution of the human skeleton
Original Paper | Bone | 2026-09-22 20:00 EDT
Yizhi Yan, Nadav Mishol, Katharina Lange, Zicong Zhang, Gal Bodek, Aya Kigel, Noam Priel, Nachshon Egyes, Omer Ronen, Itamar Nini, Liat Rotenstreich, Amit Philosoph, Sira Martinez, Silvia Beltramone, Rika Tsujikawa, Adi Rozenblatt, Lucas Esteban Wange, María Torralvo, Guy Hirsh, Yael Elboim, Sergey Viukov, Idan Korenfeld, Mythili Damal Kandadai, Océane Cluzeau, Malka Nissim-Rafinia, Eran Meshorer, Jacob H. Hanna, Evie Vereecke, Assaf Marom, Martin Kuhlwilm, Guillaume Bourque, Tomas Marques-Bonet, Simon Fishilevich, Fumitaka Inoue, David Gokhman
Skeletal modifications were central to human evolution, enabling adaptations for bipedalism, large cranial vaults and childbirth1. Despite their importance, the genetic changes that gave rise to the unique human form remain mostly unknown2. Here we systematically map the gene-regulatory changes that shaped human skeletal evolution. Using massively parallel reporter assays (MPRAs) in chondrocytes, we assayed 561,410 human-derived substitutions in promoters and enhancers, identifying 15,077 loci with human-specific regulatory activity. We then generated human-ape hybrid cells and differentiated them into osteochondral progenitors. Integrating the hybrid cells with MPRA measurements produced genome-wide atlases of human-specific changes in cis-regulatory expression, and the sequence variants that drive them. These atlases reveal an extensive rewiring of the extracellular matrix (ECM), including a marked suppression of glycosaminoglycan (GAG) biosynthesis, leading to an approximately three-to-fourfold reduction in joint GAG content in humans compared with non-human apes. We find that this human-specific shift bears signatures of selection, and is likely to be a key contributor to the exceptional susceptibility of humans to degenerative skeletal diseases3,4,5. Together, our results reveal a coordinated evolutionary remodelling of the human skeletal ECM, and establish a comprehensive framework for dissecting the genetic basis of human skeletal biology.
Bone, Evolutionary biology, Evolutionary genetics, Gene expression profiling, Gene regulation
The anthropogenic fingerprint on emerging infectious diseases
Original Paper | Ecological epidemiology | 2026-09-22 20:00 EDT
Rory Gibb, Sadie J. Ryan, David M. Pigott, Maria del Pilar Fernandez, Renata L. Muylaert, Gregory F. Albery, Daniel J. Becker, Jason K. Blackburn, Hernan Caceres-Escobar, Michael Celone, Evan A. Eskew, Hannah K. Frank, Barbara A. Han, Erin N. Hulland, Kate E. Jones, Rebecca Katz, Adam Kucharski, Direk Limmathurotsakul, Catherine A. Lippi, Joshua Longbottom, Juan Fernando Martinez, Jane P. Messina, Elaine O. Nsoesie, David W. Redding, Daniel Romero-Alvarez, Boris V. Schmid, Stephanie N. Seifert, Anabel Sinchi, Christopher H. Trisos, Michelle Wille, Colin J. Carlson
Emerging infectious diseases are a hallmark of the Anthropocene1,2. Human-driven ecosystem changes and human-wildlife-livestock contact can drive the emergence of zoonotic and vector-borne diseases3,4,5, but how much these processes shape landscapes of outbreak risk is poorly understood, beyond a few well-studied systems6,7,8. Here we consolidate 58,319 outbreak event records for 32 diseases and systematically test how 16 hypothesized social and environmental drivers impact outbreak geographies, while accounting for detection and reporting biases. We show that outbreak risks are typically highest in mosaic landscapes where people and livestock live alongside forests and fragmented ecosystems. These combined factors, along with long-term declines in precipitation, share strong impacts across several vector-borne diseases (for example, dengue, Lyme disease and zoonotic arboviruses). By contrast, directly transmitted zoonoses (for example, Ebola and mpox) share few common drivers, and the impacts of most other anthropogenic pressures (for example, deforestation, climate warming and agricultural intensification) vary widely between diseases. Most consistently, the observed geography of outbreaks is shaped by healthcare access: reporting declines by a median of 32% (range across diseases: 1.2-96.7%) for each additional hour’s travel time from a health facility. Our findings underscore that infectious disease spillover and emergence are multi-causal, and that no one-size-fits-all strategy can prevent epidemics and pandemics. Ecosystem-based public health interventions9 should always follow system-specific evidence, and be paired with greater investment in health systems and One Health pathogen surveillance.
Ecological epidemiology, Pathogens, Viral infection
Gravitational torque drives multidecadal variations in length of day
Original Paper | Core processes | 2026-09-22 20:00 EDT
Huifeng Zhang, Mathieu Dumberry
Fluctuations in the length of day (LOD) on decadal timescales are caused primarily by an exchange of angular momentum between the Earth’s mantle and core1,2,3. Several mechanisms have been proposed to explain this exchange, including electromagnetic4,5,6,7 and topographic8,9,10 coupling at the core-mantle boundary (CMB) and a gravitational torque by the inner core11,12. However, the precise nature of the core-mantle torque remains unknown. Here we show that the seismically reconstructed differential rotation of the inner core13,14,15 and core flows derived from magnetic field changes16,17 suggest that the multidecadal LOD changes are driven primarily by the gravitational torque and resisted by electromagnetic and topographic torques, consistent with results from Earth-like dynamo models18. Our reconstructed torque histories, although tied to the accuracy of the inner core rotation and core flow models, support a lowermost mantle that features near-neutrally buoyant thermochemical piles19,20,21, a post-perovskite (pPv) phase with a low viscosity22 and a highly conducting23,24 iron-enriched layer a few kilometres thick at its base25. Our results also suggest a low-viscosity inner core deforming in only a few years26,27,28 and yield an upper limit on the stratification at the top of the fluid core. Altogether, our study contributes to bringing into focus an emerging picture of the deepest regions of our planet.
Core processes, Geodynamics, Geomagnetism, Geophysics
Single-nucleus transcriptome-wide association study of human brain disorders
Original Paper | Computational models | 2026-09-22 20:00 EDT
Sanan Venkatesh, Roman Kosoy, Zhenyi Wu, Marios Anyfantakis, Christian Dillard, Prashant N. M., David Burstein, Deepika Mathur, Chris Chatzinakos, Bukola Ajanaku, Fotis Tsetsos, Biao Zeng, Sonali Gupta, Rachel Bercovitch, Aram Hong, Clara Casey, Marcela Alvia, Zhiping Shao, Stathis Argyriou, Karen Therrien, Tim Bigdeli, Pavan Auluck, David A. Bennett, Stefano Marenco, Vahram Haroutunian, Kiran Girdhar, Jaroslav Bendl, Donghoon Lee, John F. Fullard, Gabriel E. Hoffman, Georgios Voloudakis, Panos Roussos
Common brain disorders impose a substantial health burden, but localizing their genetic risk in the brain remains challenging1. Although genome-wide association studies have identified numerous loci associated with neuropsychiatric and neurodegenerative disorders, many of these loci lie in non-coding regions that influence gene expression in specific cell types2,3,4,5. Traditional bulk brain transcriptomic analyses, which often focus on European ancestry cohorts, average over cellular diversity, obscuring genetic risk-related changes in gene expression. Here we use single-nucleus gene expression profiles from the dorsolateral prefrontal cortex in the multi-ancestry PsychAD cohort to develop transcriptomic imputation models of genetically regulated expression across major brain cell types. Applying these models to neuropsychiatric and neurodegenerative disorders reveals thousands of gene-trait associations that are undetectable in bulk tissue analyses and resolves many signals to discrete neuronal, glial and immune cell populations. Cross-ancestry analyses in the Million Veteran Program confirm these associations, reveal pleiotropic effects of cell-type-specific predicted expression and demonstrate that trait-related dysregulation is conserved across ancestries, enabling mapping of causal genes and pathways. Together, these findings provide a cell-type-resolved and ancestry-aware atlas of genetically regulated expression in the human prefrontal cortex and illustrate how single-nucleus transcriptomics can sharpen gene discovery and therapeutic target prioritization for complex brain disorders.
Computational models, Data integration, Gene expression, Quantitative trait loci
Lu+ optical frequency references with accuracy verified at the 19th digit
Original Paper | Atomic and molecular physics | 2026-09-22 20:00 EDT
K. J. Arnold, M. D. K. Lee, Qi Zhao, Qichen Qin, Zhao Zhang, N. Jayjong, M. D. Barrett
Optical atomic frequency references1 have far surpassed their microwave frequency predecessors, leading to an anticipated redefinition of the SI (International System of Units) second2. However, as the scientific community seeks consensus on a new standard, and several state-of-the-art optical standards now report evaluated fractional uncertainties below 10-18, verification by same-species comparisons to comparable levels remains an outstanding challenge. Here we report two 176Lu+ single-ion optical frequency references, each with evaluated fractional frequency uncertainty near 1 × 10-19, which are directly compared by correlation spectroscopy and demonstrate agreement, with a measured relative frequency difference of [-0.1 ± (5.7)stat ± (1.0)sys] × 10-19, where ‘stat’ and ‘sys’ indicate the statistical and systematic uncertainty, respectively. Our optical references have been comprehensively assessed with evaluated uncertainties below 10-18, supported by a same-species comparison of independent systems to the 5.7 × 10-19 level. This accuracy, achieved in practical room-temperature systems, will contribute to improving international timekeeping and towards chronometric levelling3,4 at the millimetre scale, as well as tests of fundamental physics5 such as Lorentz invariance6, general relativity7, searches for dark matter8,9 and variation of fundamental constants10,11.
Atomic and molecular physics, Optical spectroscopy
Sequence-encoded hexagonal lattices in multichannel peptide nanofibrils
Original Paper | Materials science | 2026-09-22 20:00 EDT
Jasmina Gačanin, Francesca Mazzotta, Luis Andre Baptista, Nikolay Stoyanov, Matthias Schmidt, Nico Alleva, Thunchanok Thummaraj, Fanny Bonnicel, Cong Zhou, Lei Gao, Jan Münch, Mischa Bonn, Marcus Fändrich, Ingo Lieberwirth, Robinson Cortes-Huerto, Katharina Landfester, Tanja Weil
Structural complexity in biological matter arises from molecular information that encodes supramolecular assembly across length scales1,2,3. Here we show that minimal nine-residue peptides can encode discrete lateral interaction motifs that direct supramolecular organization. These motifs generate hexagonal pores and hierarchically tile into multichannel nanofibrils with defined topology. Sequence-encoded amphiphilicity combines a cross-β-dimer, an inversion point and a trimeric junction to create complementary interfaces that couple lateral growth to axial stacking, yielding honeycomb lattices with continuous approximately 5-nm solvent-accessible nanochannels. Cryo-electron microscopy resolves the supramolecular architecture and shows that lattice symmetry and pore geometry are preserved across variants. Systematic perturbations establish sequence-structure rules linking residue position to supramolecular symmetry, lattice propagation and channel topology. Molecular dynamics simulations and vibrational spectroscopy show that the channels remain water accessible and show sequence-tunable hydration. These findings establish that a minimal, sequence-encoded interaction hierarchy can programme long-range supramolecular order, providing a general framework for how short peptides can encode complex, symmetry-defined architectures4,5,6,7,8,9,10,11,12.
Materials science, Molecular self-assembly, Self-assembly, Structural biology, Supramolecular chemistry
Banking records reveal characteristics of financial abuse
Original Paper | Economics | 2026-09-22 20:00 EDT
Anna Trendl, Nicola Sharp-Jeffs, Karen Perrier, Jane Rodrick, John Gathergood, David Leake
The experience of financial abuse, a form of domestic abuse involving control over money and finances, can be severe and long-lasting1,2,3, yet difficult to document4. Evidence on the everyday experiences of victim-survivors in the context of financial abuse is drawn primarily from small-scale, qualitative surveys5,6. Using anonymized banking data from a major UK retail bank, we compared the financial outcomes of a group of female victim-survivors of financial abuse (n = 5,428; identified from customer disclosures to the bank) with a control group (n = 15,602; consisting of individuals with no known disclosures). The control group matched the demographic and socioeconomic characteristics of the victim-survivor group 7 years before disclosure. A comprehensive set of 373 transactional and non-transactional financial outcomes were analysed over this period. Results indicate that, compared with controls, victim-survivors exhibited depleting savings and increasing debts, culminating in missed payments and declining credit scores. They also spent less on self-care, incurred higher transport and legal costs, increased cash withdrawals, changed addresses and passwords more frequently and were more likely to claim welfare benefits. Our results demonstrate how victim-survivors lose financial independence, experience economic instability and suffer financial distress.
Economics, Human behaviour, Interdisciplinary studies
Hepatocytes promote liver metastasis of pancreatic cancer by providing serine
Original Paper | Cancer metabolism | 2026-09-22 20:00 EDT
Koelina Ganguly, Keisuke Yamamoto, Jason Rodencal, Joel Encarnacion-Rosado, Albert S. W. Sohn, Douglas E. Biancur, Elaine Y. Lin, Ruohong Wang, Carolina Alcantara Hirsch, Anthony Sorrentino, Elshaddai Z. White, Paul M. Grandgenett, Michael A. Hollingsworth, Miwako Kakiuchi, Richard Possemato, Dafna Bar-Sagi, Mitsuhiro Fujishiro, Alec C. Kimmelman
The liver is the primary site of metastasis in pancreatic ductal adenocarcinoma (PDAC), and liver metastases are a major cause of mortality1,2. Nutrient availability in the metastatic niche influences colonization efficiency; however, the metabolic heterogeneity of disseminated tumour cells can also reshape the local microenvironment3,4,5. Loss of phosphoglycerate dehydrogenase (PHGDH), the rate-limiting enzyme in de novo serine biosynthesis, is observed in nearly 40% of PDACs, and renders these cells dependent on exogenous serine (exSer)6. Although a neuron-tumour metabolic cross-talk supports exSer-dependent PDAC cells at the primary site6, it remains unclear how these cells adapt to the metastatic liver niche. Here we show that exSer-dependent PDAC cells reprogram neighbouring hepatocytes through a CXCL5-CXCR2 axis. Activation of CXCR2 in hepatocytes promotes PI3K-AKT signalling, leading to the sequestration of FOXO3A in the cytoplasm and derepression of PHGDH transcription, thereby enhancing serine production in hepatocytes. This hepatocyte-derived serine supports the outgrowth of exSer-dependent PDAC liver metastases. Accordingly, genetic or pharmacological inhibition of individual nodes within the CXCL5-CXCR2-PI3K-AKT-FOXO3A axis, or hepatocyte-specific deletion of Phgdh or Cxcr2, markedly reduces the liver-metastasis burden in mice and prolongs survival, particularly when dietary serine is restricted. Our findings reveal a cancer cell-hepatocyte metabolic cross-talk and identify therapeutic targets for exSer-dependent PDAC liver metastases.
Cancer metabolism, Cancer microenvironment, Pancreatic cancer
A design approach for bitopic kinase inhibitors
Original Paper | Chronic myeloid leukaemia | 2026-09-22 20:00 EDT
Jack W. Stevenson, Kevin Lou, Joshua A. Reynolds, Ian R. Outhwaite, Kenneth Huang, Ivan Sokirniy, Sky Y. J. Peterson, Amir Z. Munir, Celine D. Wang, Haider Inam, Emma L. Gebauer, Ariel Leyte-Vidal, Anastasiia Grynyova, Sydney M. Figueroa, Matthew G. Rees, Melissa M. Ronan, Fernando Salangsang, Yan Zeng, Veronica Steri, Jennifer A. Roth, Neil P. Shah, Ignacia Echeverria, Andrej Šali, Ziyang Zhang, Javid J. Moslehi, Markus A. Seeliger, Justin R. Pritchard, Kevan M. Shokat
Traditional kinase inhibitors face a trade-off between potency and selectivity because their affinity depends on limited molecular interactions in a single highly conserved binding site. Bitopic inhibitors overcome this limitation by engaging multiple sites on the same target1. Here, using ABL1 and EGFR as model kinases, we systematically explore the bitopic-specific design parameters of ligand choice, linkage vector and linker length and show that they affect potency through inter-ligand cooperativity and linker entropy. We apply this approach to address an unmet clinical need: existing inhibitors of ABL1, an important target in BCR::ABL1-driven leukaemias, are constrained by resistance mutations and off-target effects2. The third-generation inhibitor ponatinib overcomes many resistance mutations, but cardiovascular toxicity limits its clinical use3. We design a bitopic ABL1 inhibitor, PonatiLink-2, that maintains or surpasses the potency of ponatinib against resistance mutants. Moreover, it has an enhanced therapeutic window in vitro and in vivo, which enables increased dosing without apparent toxicity. PonatiLink-2 outperforms clinically relevant treatments in mouse models of BCR::ABL1-driven cancer, both in combination with dasatinib against wild-type BCR::ABL1 and as a single agent against ponatinib-resistant disease. These findings indicate that the bitopic design approach is a promising strategy for developing potent, well-tolerated clinical inhibitors of ABL1 and other targets.
Chronic myeloid leukaemia, Drug discovery and development, Kinases, Small molecules
A methanogen hydrolase reveals the structure of archaeal peptidoglycan
Original Paper | Cell division | 2026-09-22 20:00 EDT
Robert Smith, Nika Pende, Aline Rifflet, Najwa Taib, Jerzy Witwinowski, Camille Martin-Gallausiaux, Charlène Cornilleau, Pierre Simon Garcia, Romain Villa, Thibaut Douché, Mariette Matondo, Manuel Majrouh, Robert Reichelt, Dina Grohmann, Patrick Tripp, Sonja-Verena Albers, Guillaume Borrel, Simon K.-M. R. Rittmann, Anna Sartori-Rupp, Richard Wheeler, J. Iñaki Guijarro, Ivo Gomperts Boneca, Simonetta Gribaldo
Peptidoglycan (PG) is a near-universal and essential feature of bacterial cell walls and a major antimicrobial target1. Although archaea generally lack PG2, a PG-like polymer (pseudomurein or archaeal PG) was described decades ago in a major clade of methanogenic archaea3,4,5,6,7,8, yet it has remained poorly characterized, owing to the lack of dedicated analytical tools. Here we identify and characterize ArmA from Methanobrevibacter smithii, a dominant member of the human gut microbiome9, as the first glycosyl hydrolase specific for archaeal PG. ArmA-mediated digestion reveals an unexpected architecture that revises the prevailing model of archaeal PG. The glycan backbone comprises N-acetylglucosamine/N-acetylgalactosamine linked to a previously undescribed sugar, which we name N-acetylarmosamine. Glycan strands alternate β(1,4) and β(1,3) linkages, and the stem peptide is attached by means of an amide bond to the N-acetylarmosamine succinyl group. ArmA has dual enzymatic activity, cleaving both glycosidic linkages and peptide crosslinks. Phylogenetic analyses show that ArmA homologues are restricted to PG-bearing archaea, and we confirm activity across diverse methanogens. We further demonstrate that ArmA is required to complete cytokinesis, cleaving archaeal PG at the site of cell division. Together, these findings overturn a 50-year-old paradigm on archaeal PG structure and establish ArmA as a critical tool that parallels the impact of muramidases in bacteria, enabling biochemical and genetic interrogation of methanogen cell-wall biology. Finally, given the ecological and biotechnological importance of methanogens10,11, our results open new avenues for targeted intervention.
Cell division, Cell growth
Reference genomes and fossils revise bat family phylogeny and biogeography
Original Paper | Biogeography | 2026-09-22 20:00 EDT
Ariadna E. Morales, Yan Liang
(梁妍), William R. Thomas, Evgeny V. Leushkin, Francisco X. Castellanos, Denis M. Larkin, Tom Brown, Bastian Fromm, Suzanne J. Hand, Zixia Huang, Graham M. Hughes, Matthew F. Jones, Burton K. Lim, Meike Mai, Eugene W. Myers, Martin Pippel, Sebastien J. Puechmaille, Nancy B. Simmons, Linelle Ann L. Abueg, Nadav Ahituv, Zahran A. AlAbdulsalam, Ine Alvarez van Tussenbroek, Dineilys V. Aparicio, Lina M. Arcila Hernández, Alexander Ben Hamadou, Petr Benda, Mark Blaxter, Alex V. Borisenko, Jorge Brocca, Nair Cabezón, Lucia Carbone, Jose I. Carvajal, Wharton O. Y. Chan, Paul Davis, Dina K. N. Dechmann, Annette Denzinger, Judith L. Eger, Seth J. Eiseb, David Enard, Mark D. Engstrom, Nicole M. Foley, Giulio Formenti, Jackson Fuller, Ismael Galván, Akshamal M. Gamage, Neil J. Gemmell, Joanne E. Gillum, Alejandro Gonzales-Irribarren, Mailyn A. Gonzalez, Steven M. Goodman, Jonathan Gray, Carola Greve, Michael W. Guernsey, Edgar G. Gutiérrez, Yelena Guttman, Michael Hackenberg, Elena Hilario, Leon Hilgers, Thomas W. Horsley, Melissa R. de Waal, Deirdre M. Jafferally, Erich D. Jarvis, Sahieda A. Joemratie, Mirjam Knörnschild, Jenna E. Kohles, Dimitrios-Georgios Kontopoulos, Bonhwang Koo, M. Elise Lauterbur, Michael Letko, Harris A. Lewin, Shenglin Liu, Darrell K. Lizamore, Brian D. Lloyd, Livia Loureiro, M. Cristina MacSwiney G, Yury V. Malovichko, Kirsty McCaffrey, Dominik W. Melville, Magdalena Meyer, William O. Mgoola, Matthieu Muffato, Vincent J. Munster, William J. Murphy, Martina Nagy, Nicolas Nesi, Kimberly A. Nevonen, Haris Nicolaou, Evans E. Nkrumah, Zacharias Norman, Brian P. O’Toole, Sarah H. Olson, Alain Ondzie, Bismark A. Opoku, Jorge Ortega, William S. Pearman, Francy J. Perez-Llanos, Kendra L. Phelps, Myrtani Pieri, Sarahjane Power, Maksym Prylutskyi, Paola Pulido-Santacruz, Guoying Qi, Bernal Rodríguez-Herrera, Danny Rojas, Indranee Roopsind, Stephen J. Rossiter, Constance Scharff, Tilman Schell, Stephanie N. Seifert, Fernando Simal, Pipat Soisook, Simone Sommer, Andrew Spalton, Emma L. Stone, Peter H. Sudmant, Sam Talbot, Robert M. Timm, Laura Uelze, Nathan S. Upham, Marek Uvizl, Peter Vallo, Juan M. Vazquez, Lin-Fa Wang, Linet C. Watson, Daniel Whitby, Sylke Winkler, York Winter, Laurel R. Yohe, Monika Zavodna, Ning Zhang, Huabin Zhao, David A. Ray, Sonja C. Vernes, Liliana M. Dávalos, Michael Hiller, Emma C. Teeling
Bats are extraordinary among mammals, having uniquely evolved powered flight and laryngeal echolocation, along with disease resistance, extended healthspans and the ability to hibernate1. However, the evolutionary history of bats and the understanding of these adaptations remain unresolved. We analysed chromosome-level, long-read genome assemblies from 103 bat species, including 42 new assemblies, representing all 21 bat families. This dataset, expanded in scope and assembly quality, yielded a new bat phylogeny. We placed Myzopodidae as the earliest branch within Vespertilionoidea, and resolved yangochiropteran relationships, identifying Emballonuroidea and Vespertilionoidea as sister groups. Our analysis revealed a mosaic evolutionary history across bats and explained why previous phylogenetic studies were misled. Chromosomal ancestral-state reconstructions supported 26 ancestral bat chromosomes. We integrated a morphological dataset of 699 characters for 65 species, including 44 pre-Quaternary fossils and representatives of most living bat families, with neutrally evolving genomic sites. Fossilized birth-death and dispersal-extinction cladogenesis analyses showed that bats, and thus powered flight, probably originated in Europe in the late Palaeocene, refuting African and North American origins. Placement of the fossil †Vielasia in the oldest ‘Eochiroptera’ clade indicates that laryngeal echolocation predates crown-bat diversification. Total evidence dating, including the fossil taxa, significantly reduced unrepresented basal branch lengths compared with molecular-only divergence estimates. By integrating comprehensive genomic and morphological datasets, analysed using innovative methods, we resolve long-standing controversies in bat biology and provide new insights into the evolutionary history and trait diversification of bats.
Biogeography, Chromosomes, Genomics, Palaeontology, Phylogenetics
mTORC1 drives cell-autonomous astrocyte reactivity in tuberous sclerosis
Original Paper | Developmental disorders | 2026-09-22 20:00 EDT
Thomas L. Li, John D. Blair, Taesun Yoo, Gerald A. Grant, Dirk Hockemeyer, Brenda E. Porter, Helen S. Bateup
Tuberous sclerosis complex (TSC) is a genetic neurodevelopmental disorder characterized by focal brain malformations called cortical tubers, which are associated with severe, intractable epilepsy1. Tubers are thought to result from somatic second-hit mutations that disrupt the TSC1 or TSC2 genes in neural progenitor cells, driving hyperactive mTORC1 signalling2. Glial abnormalities are commonly observed in tubers3; however, whether glia actively cause disease or merely result from chronic seizure activity has remained unclear. To address this question, we used human brain organoid models to track the developmental fate of mutated progenitor cells in the absence of seizures. Here we show, using single-cell transcriptomics and cyclic immunostaining across human brain organoids and resected tuber tissue from patients, that loss of TSC2 biases neural progenitors to differentiate into enlarged, pro-inflammatory reactive astrocytes in a cell autonomous manner. These mutant astrocytes show downregulated glutamate transporter expression, increased inflammatory cytokine secretion and elevated expression of neurodegenerative disease risk genes such as APOE and CLU. Our findings demonstrate that reactive astrocytes emerge as a primary consequence of TSC2 loss. These results implicate glial dysfunction as a driver of TSC pathogenesis and highlight reactive astrocytes as potential therapeutic targets for TSC-related neuropathology.
Developmental disorders, Molecular neuroscience
Targeting ZMYND8 unleashes IL-2 signalling to override T cell exhaustion
Original Paper | Immunosurveillance | 2026-09-22 20:00 EDT
Yan Wang, Hao Shi, Nicole M. Chapman, Anil KC, Renqiang Sun, Hao Song, Xiaoxi Meng, Xiang Sun, Hongbo Chi
CD8+ T cell exhaustion impedes control of chronic viral infection and cancer. This hypofunctional state is characterized by downregulation of the high-affinity IL-2 receptor (IL-2R) and STAT5 signalling, and differentiation from progenitor exhausted to terminally exhausted T cells rather than cytotoxic effector-like cells1,2,3. The epigenetic mechanisms and regulatory networks that mediate IL-2R-STAT5 signal attenuation and loss of effector-like cell differentiation remain unknown. Here, using in vivo single-cell CRISPR screens of epigenetic factors and IL-2 signalling regulators, we reveal that the chromatin reader ZMYND8 antagonizes IL-2R-STAT5 signals to restrain effector-like states while promoting terminal exhaustion. ZMYND8 expression was upregulated by chronic antigen stimulation, and targeting ZMYND8 in CD8+ T cells promoted both intermediate exhausted T cells and killer cell lectin-like receptor-expressing exhausted T cells. Accordingly, ZMYND8-deficient CD8+ T cells had markedly improved antiviral and antitumour effects, especially in combination with IL-2 therapy or immune checkpoint blockade. Mechanistically, ZMYND8 bound to the active enhancer regions of the Il2ra gene locus that were co-occupied by histone acetyltransferase p300 and suppressed p300 activity. Co-deletion of p300 reversed increased IL-2R expression and effector-like cell differentiation in ZMYND8-deficient cells, suggesting that ZMYND8 represses p300-mediated transcriptional activation to curtail IL-2R-STAT5 signalling. These findings establish an epigenetic rheostat imposing ‘signal 1’ (chronic antigen stimulation)-induced suppression of ‘signal 3’ (IL-2 signalling) to enforce T cell exhaustion, with ZMYND8 deletion unleashing effector-like over terminally exhausted states and enhancing immunotherapeutic efficacy.
Immunosurveillance, Lymphocyte differentiation
Anomalous metal and superconducting phases in rhombohedral graphene
Original Paper | Electronic properties and materials | 2026-09-22 20:00 EDT
Anna Okounkova, Abigail Sohm, Tobias Faehndrich, Manish Kumar, Derek Waleffe, Jiaqiang Yan, Kenji Watanabe, Takashi Taniguchi, Joshua Folk, Matthew Yankowitz
Two-dimensional superconductivity is now well established in graphene-based systems, with many such realizations showing evidence for unconventional pairing1,2,3,4,5,6. Yet, in several of the gate-tuned phases that otherwise exhibit clear signatures of superconductivity, the resistance does not vanish as temperature is lowered, instead saturating at a finite value2,6,7,8,9,10,11,12,13,14,15. Here we report a systematic study of this behaviour in rhombohedral graphene on a WSe2 substrate, finding regions of gate space with zero-resistance superconductivity alongside others with finite saturation resistance. At zero magnetic field, these regions appear as isolated pockets in gate space that otherwise exhibit very similar phenomenology, including abrupt transitions to the normal state as temperature, perpendicular magnetic field and current are raised above critical values. A small in-plane field expands and merges these pockets without qualitatively altering their behaviour, producing a sharp boundary at millikelvin base temperature between states of zero or finite resistance. The finite-resistance state reproduces key phenomenology associated with the anomalous metal, a state that has been observed in thin-film superconductors for decades but lacks an accepted theoretical explanation16,17. The tunability and reproducibility of ultra-clean rhombohedral graphene place strong constraints on extrinsic explanations and provide a new platform for understanding this behaviour.
Electronic properties and materials, Superconducting properties and materials
Lifespan single-cell transcriptomic atlas of the human prefrontal cortex
Original Paper | Cognitive ageing | 2026-09-22 20:00 EDT
Hui Yang, Tereza Clarence, Madeline R. Scott, Xinyi Wang, Prashant N. M., Milos Pjanic, Sanan Venkatesh, Aram Hong, Clara Casey, Sarah R. Murphy, Zhiping Shao, Marcela Alvia, Stathis Argyriou, Alexander Kawah Yu, Nadejda M. Tsankova, Pavan K. Auluck, Stefano Marenco, Vahram Haroutunian, Georgios Voloudakis, Jaroslav Bendl, Colleen A. McClung, Donghoon Lee, John F. Fullard, Gabriel E. Hoffman, Kiran Girdhar, Panos Roussos
The human brain undergoes profound changes from early development through late adulthood, shaping cognition, behaviour and vulnerability to disease1,2. Understanding how these changes are organized within specific brain regions and cell types is essential for interpreting normal ageing and its relationship to psychiatric and neurodegenerative disorders. The dorsolateral prefrontal cortex has a central role in higher cognitive functions and is particularly sensitive to age-related decline3, yet its cellular and molecular programs across the human lifespan remain poorly defined. Most existing studies4,5,6,7 have focused on restricted age ranges or disease-affected brains, limiting the ability to distinguish normative developmental and ageing trajectories from pathological processes. Consequently, a comprehensive, lifespan-resolved reference of cellular states in the human prefrontal cortex has been lacking. Here, using a single-nucleus transcriptomic atlas spanning the human lifespan, we show that the dorsolateral prefrontal cortex exhibits non-linear, cell-type-specific transcriptional trajectories characterized by dynamic remodelling during development, relative stability in midlife and selective molecular reactivation in late adulthood. We identify distinct neuronal and glial programs, including early-life neuronal resilience pathways and late-life glial programs associated with immune activation, stress responses and circadian reorganization. These programs are anatomically organized across cortical layers and grey-white matter domains, revealing coordinated spatial and molecular changes. Together, these findings provide a framework for understanding how cellular programs transition from resilience to vulnerability in the human cortex and establish a foundation for interpreting age-related cognitive decline and disease risk.
Cognitive ageing, Data processing
Agricultural liming is a carbon sink in the Mississippi River Basin
Original Paper | Carbon cycle | 2026-09-22 20:00 EDT
Tim Jesper Suhrhoff, Christopher T. Reinhard, Yoshiki Kanzaki, Samuel Shou-En Tsao, Beck Woollen, Tom Reershemius, Samuel Shaheen, James Saiers, Shuang Zhang, Peter A. Raymond, Noah J. Planavsky
Application of carbonate minerals to arable lands, known as agricultural liming, is a long-standing practice for counteracting soil acidification1,2,3. Although liming boosts crop yields4, it is also considered a source of agricultural carbon dioxide (CO2) emissions5. Here we show, using century-scale records of agricultural liming and anthropogenic acidity inputs for the Mississippi River Basin, that agricultural liming has acted as a net carbon sink over the past century. Records of river alkalinity fluxes suggest that approximately 90% of the ideal CO2 removal potential of agricultural lime added since 1900 (approximately 0.44 GtCO2) has been realized at the catchment scale, with a decadal-scale time lag owing to soil cation exchange and solute transport. These results are consistent with reactive transport modelling of soil cation throughput, which indicates that net CO2 removal emerges after an initial emissions pulse associated with neutralization of soil acidity pools. Current accounting frameworks implicitly apply an incomplete counterfactual, attributing CO2 emissions to lime addition rather than to the anthropogenic acidity inputs that drive CO2 release. Evaluated against the counterfactual of anthropogenic acidity inputs, agricultural liming represents a net carbon sink in the Mississippi River Basin on decade-to-century timescales. These results suggest that optimized soil pH management can reduce agricultural greenhouse gas emissions while simultaneously improving crop yields and soil health.
Carbon cycle, Geochemistry, Hydrology
Stacking-induced direct band gap in CVD-grown 1H MoS2 bilayers
Original Paper | Materials for optics | 2026-09-22 20:00 EDT
Tilo H. Yang, I-Tong Chen, Min-Jia Zhang, Ju-Yi Huang, Tzu-Hao Kuo, Shao-Yu Chen, Hsing-Yeh Li, Ying-Chun Chao, Zachariah B. Hennighausen, Vo Khuong Dien, Heng-Wen Wei, Meng-Che Wu, Hung-Wei Yen, Tzu-Hung Chuang, Der-Hsin Wei, Jing Kong, Ting-Hua Lu, Kuang-I Lin, Yann-Wen Lan
Bilayer transition metal dichalcogenides offer superior electronic properties over their monolayer counterparts, such as higher carrier mobility and electrically switchable polarity1,2,3,4, positioning them as attractive candidates for next-generation transistors1,5 and sliding ferroelectric devices6,7. However, their inherent indirect band gap severely limits light emission, hindering their integration into optoelectronic systems1,2,5,8,9,10. Here we show bilayer MoS2 with 1H stacking obtained by a two-step chemical vapour deposition process, yielding atomically precise vertical alignment. The 1H bilayers exhibit a direct band gap, as confirmed by angle-resolved photoemission spectroscopy and density functional theory calculations. Photoluminescence measurements show intensified excitonic emission and the absence of indirect bandgap features. Furthermore, these bilayers exhibit stronger valley polarization than monolayers under both resonant and nonresonant excitation, primarily because of the suppressed intervalley scattering in the top layer. Together, these results establish 1H MoS2 as a model system for stacking-engineered quantum materials and underscore its potential for valleytronic and optoelectronic applications.
Materials for optics, Synthesis and processing, Two-dimensional materials
TRAM promotes Toll-like-receptor-free myddosome signal transduction
Original Paper | Innate immunity | 2026-09-22 20:00 EDT
Daniel Fisch, Vaani Ohri, Eleni Anastasakou, Lucia J. Wesemann, Joon H. Choi, Katherine E. Lindblad, Jonathan C. Kagan
In the Toll-like receptor (TLR) signal transduction pathways, activated receptors are present for mere minutes within the initial, membrane-proximal signalling complexes called proto-myddosomes1. Proto-myddosomes are rapidly released from TLRs to self-assemble (that is, mature) into enzyme-rich, cytosolic supramolecular organizing centres called myddosomes2,3,4. Myddosomes induce hours-long inflammatory gene expression5,6,7,8,9,10. The mechanism controlling proto-myddosome release and its effect on signal transduction are undefined. Here we identify factors that regulate the maturation process of proto-myddosomes into receptor-free cytosolic myddosomes11. Through a genetic screen in macrophages, we identify TRAM, which was previously described to control MyD88-independent TLR signalling, as a regulator of myddosome assembly. Using biochemistry, live-cell imaging and activity reconstitution with recombinant proteins, we show that the plasma-membrane-associated adapter TIRAP seeds proto-myddosomes12,13, after which TRAM dissociates MyD88 from the TLR-TIRAP complex to enable myddosome maturation and downstream signal transduction14,15,16,17,18,19. In the absence of TRAM, MyD88 cannot dissociate from the TLR-TIRAP complex, resulting in abnormal and unstable MyD88 interactions with downstream signalling enzymes. These findings enabled us to identify TRAM-dependent long-lasting myddosome activities as the determinant of two TLR pathway hallmarks: hours-long NF-κB activation20,21,22,23,24 and secondary response gene expression25,26,27. Chemical dissociation of cytosolic myddosomes disrupted existing inflammatory activities of TLR-stimulated cells in vitro and in vivo. Collectively, this work establishes TRAM as a regulator of myddosome maturation and signalling, providing the molecular basis for receptor-free signal transduction.
Innate immunity, Signal transduction
Lsp2 links mTORC1 to TOP mRNA translation and lifespan in Drosophila
Original Paper | Ageing | 2026-09-22 20:00 EDT
Jun Wang
(王骏), Zixin Cai
(蔡子欣), Jiaojiao Gu
(谷姣姣), Shiqi Xiong
(熊诗琪), Jianhan Yi
(易翦涵), Meng Yang
(杨猛), Kexin Chang
(常可忻), Xinrui Ning
(宁鑫蕊), Yilin Wen
(闻溢琳), Yan Yan
(阎言), Jiongming Lu
(陆炯明), Yirong Wang
(王奕蓉), Zongzhao Zhai
(翟宗昭)
Mechanistic target of rapamycin complex 1 (mTORC1) senses nutrient availability to orchestrate metabolic processes that are crucial for physiological homeostasis and ageing1. mTORC1 preferentially regulates the translation of 5’-terminal oligopyrimidine (TOP) motif-containing mRNAs (which encode mainly ribosomal proteins) through the 4E-BP translational repressor2; however, this function of mTORC1 is resistant to rapamycin inhibition3. TOP mRNAs are exceptionally abundant, and thus impose a major translational burden on cells, but how their translation is physiologically tuned and linked with lifespan remains unclear. Here we show that Lsp2, which was previously known to be a storage protein4, is also an adipose effector and feedback activator of mTORC1 that modulates lifespan in Drosophila. Expression of Lsp2 is induced by essential amino acids through mTORC1 and is gated by additional signals of nutrient sufficiency. Genetic ablation of Lsp2 robustly extends lifespan without impairing key life history traits such as reproduction. Translatomic profiling shows that loss of Lsp2 selectively reduces global TOP mRNA translation in a 4E-BP-dependent manner, thereby extending lifespan through a mechanism distinct from the effects of rapamycin. Evolutionarily, TOP motifs co-emerged with 4E-BP and are present in nearly all Drosophila ribosomal protein mRNAs. Moreover, we show that the role of TOP motifs in translational control extends to Drosophila. Collectively, our findings reveal a nutrient-induced physiological factor that amplifies mTORC1 output in TOP mRNA translation and regulates organismal longevity.
Ageing, Animal physiology, Ribosome, Senescence, TOR signalling
Lsp2 links early-life diet to adult translation and lifespan in Drosophila
Original Paper | Ageing | 2026-09-22 20:00 EDT
Hina Kosakamoto, Rina Okada, Clive S. Barker, Ayako Isomura-Matoba, Jun Seita, Naoshi Dohmae, Koshi Imami, Fumiaki Obata
Nearly a century ago, restricting diet during early-life periods was suggested to extend lifespan in rats and in Daphnia1,2. The effect of juvenile diet on adult physiology and lifespan has subsequently been described in other model organisms, including fruit flies3,4,5 and mice6,7,8; however, its mechanism remains poorly understood. Here, using Drosophila as a model, we show that restricting protein intake during the larval stage (early-life protein restriction; ePR) promotes adult lifespan by reducing the levels of storage proteins. Using stable-isotope tracing, we show that dietary amino acids obtained in the larval stage are retained into early adulthood, and are incorporated into ribosomal proteins in particular. This is mediated by larval serum protein 2 (Lsp2), a major storage protein, the expression of which is durably downregulated by ePR in the early adult stage. Genetic silencing of Lsp2 phenocopies ePR, attenuating ribosomal-protein abundance and translational activity in early adulthood, and extending lifespan. Restricting specific amino acids that are especially enriched in these storage proteins, such as phenylalanine and tyrosine, is sufficient to decrease the levels of early-life Lsp2 and promote longevity. These findings identify Lsp2 as a molecular carrier of nutritional history across developmental transitions, linking juvenile nutritional status to adult translational capacity and lifespan. Our study uncovers a previously unrecognized mechanism of nutritional memory that links early-life diet to lifelong organismal health.
Ageing, Metabolism
The lipidomic architecture of the mouse brain
Original Paper | Cellular neuroscience | 2026-09-22 20:00 EDT
Luca Fusar Bassini, Halima Hannah Schede, Laura Capolupo, Leila Haj Abdullah Alieh, Irmak Kaysudu, Francesca Venturi, Hannah Hochgerner, Alessandro Valente, Colas Droin, Daniel Trejo Banos, Irina Khven, Jean Andrea Maillat, Anne-Laure Mahul-Mellier, Antonino Asaro, Doğukan H. Ülgen, Pavel Barahtjan, Ece Z. Asirim, Anita Nasrallah, Carmen Sandi, Ekaterina Krymova, Giovanni D’Angelo, Gioele La Manno
Lipids are fundamental components of the brain, crucial for synaptic transmission and signal propagation. Altered brain lipid composition is associated with common and rare neuropathologies, yet the spatial organization of the mammalian brain lipidome remains insufficiently characterized compared with other modalities1,2,3,4,5,6. Here we mapped the membrane-lipid architecture of the adult mouse brain at micrometric scale, across sexes and during pregnancy. This lipid brain atlas reveals that lipids describe a fine-grained biochemical structure that aligns with functional anatomy. Membrane-lipid spatial heterogeneity clusters into territories, which we termed ‘lipizones’. Lipizones partially mirror cell-type territories, but also capture distal axon terminals. Through lipizones, we (1) reveal the organizing principles of the grey matter lipidome, related to connectivity and cytoarchitecture; (2) discover a new axis of oligodendrocyte heterogeneity in the white matter; and (3) find biochemical zonation in the choroid plexus and in the ventricular walls. We show that this lipidomic architecture can adapt to changing physiological needs. In the brain of pregnant female mice, the white matter is metabolically activated and the cortex undergoes a lipizone-specific remodelling that is particularly pronounced in layer 4. These results are a foundational resource (https://lbae-v2.epfl.ch/) poised to reshape the understanding of lipids in brain development, physiology and pathology.
Cellular neuroscience, Lipidomics, Molecular neuroscience, Multicellular systems
Single-cell atlas of transcriptomic vulnerability across brain disorders
Original Paper | Alzheimer’s disease | 2026-09-22 20:00 EDT
Donghoon Lee, Mikaela Koutrouli, Nicolas Y. Masse, Gabriel E. Hoffman, Seon Kinrot, Xinyi Wang, Prashant N. M., Milos Pjanic, Tereza Clarence, Fotios Tsetsos, Deepika Mathur, David Burstein, Karen Therrien, Aram Hong, Clara Casey, Zhiping Shao, Marcela Alvia, Stathis Argyriou, Jennifer Monteiro Fortes, Sarah R. Murphy, Pavel Katsel, Pavan K. Auluck, Lisa L. Barnes, Stefano Marenco, David A. Bennett, Lars Juhl Jensen, Kiran Girdhar, Georgios Voloudakis, Vahram Haroutunian, Jaroslav Bendl, John F. Fullard, Panos Roussos
Neurodegenerative and neuropsychiatric diseases impose a considerable societal and public health burden. However, our understanding of the molecular mechanisms underlying these highly complex conditions remains limited1,2. Here, to gain deeper insights into the aetiology of different brain diseases, we used specimens from 1,494 unique donors to generate a population-scale single-cell transcriptomic atlas of the human dorsolateral prefrontal cortex, comprising over 6.3 million individual nuclei. The cohort includes neurotypical controls, as well as donors affected by eight common and complex brain disorders: Alzheimer’s disease (AD), diffuse Lewy body disease (DLBD), vascular dementia (Vas), Parkinson’s disease (PD), tauopathy, frontotemporal dementia, schizophrenia, and bipolar disorder. We show that interindividual variation accounts for a substantial portion of gene expression variation. By comparing transcriptomic variation across diseases, we reveal universal signatures enriched in basic cellular functions such as mRNA processing and protein localization. After discounting these cross-disease signatures, we show stronger genetic and transcriptomic concordance among AD, DLBD, Vas and PD. Furthermore, we characterize transcriptomic variation among different AD phenotypes, distinct from those observed in healthy ageing, revealing a reduction in neuronal abundance in individuals with more severe AD, coupled with an increase in immune and vascular cell populations. Exploring the neuropsychiatric symptoms (NPSs) that frequently accompany AD, we find an increased abundance of deep-layer excitatory neurons associated with a broad range of NPSs. By constructing transcriptome trajectories that capture AD progression, we implicate cell-type-specific responses in the early and late stages of AD. Our disease atlas provides a perspective of the transcriptomic landscape in neurodegenerative and neuropsychiatric disorders, shedding light on shared and distinct processes involving the neurological-immune-vascular systems, and identifying potential targets for therapeutic intervention.
Alzheimer’s disease, Bipolar disorder, Neurodegeneration, Parkinson’s disease, Schizophrenia
MMEJ repair of breaks at TA repeats maintains ecDNA and cancer fitness
Original Paper | Cancer genomics | 2026-09-22 20:00 EDT
David Billing, Monica Selvaraj, Megan E. Kelley, Gabriel Matos-Rodrigues, Benton Bailey, Finnja Becker, Gang Zhen, Matthew A. Myers, Alessandra Brambati, Oluchi Ezekwenna, Ashley Nichols, Yi-Zhen Jiang, Lucia Wang, Shih-Chun Wang, Marie-Claude Mathieu, Davide Pradella, Hugo Poirier, Elias Rodriguez-Fos, Stephen J. Morris, Michal Zimmermann, Elsa Callen, Michael Zinda, Andrea Ventura, John Maciejowski, Andrew McPherson, Sohrab P. Shah, Anton George Henssen, André Nussenzweig, Agnel Sfeir
Extrachromosomal DNA (ecDNA) comprises megabase-sized circular DNA elements that frequently carry oncogene amplifications, driving aggressive tumour phenotypes, therapeutic resistance and poor clinical outcomes across many cancers1,2,3,4. Although ecDNA is thought to arise from canonical double-strand break repair, the pathways that maintain it remain unclear. Here we show that inhibition of microhomology-mediated end joining, but not non-homologous end joining or homologous recombination, selectively depletes ecDNA, induces ecDNA-specific damage and promotes its sequestration into micronuclei, compromising the fitness of cancer cells that depend on ecDNA-driven oncogene amplification. Mechanistically, TA-rich loci on ecDNA are hotspots for DNA damage and breakage5,6. The DNA translocase FANCM suppresses break formation at these sites, while breaks that escape FANCM surveillance are cleaved by ERCC1-ERCC4 and channelled into microhomology-mediated end joining for repair. Single-cell whole-genome sequencing shows that disrupting FANCM or polymerase θ (Polθ) in COLO320DM cells causes structural instability characterized by deletions and small duplications, with breakpoints enriched at TA-rich regions. This fragility is recapitulated in human tumours, in which ecDNA rearrangements are enriched at TA repeats. Collectively, our findings reveal TA repeat fragility as an intrinsic vulnerability of circular DNA and identify Polθ inhibition as a promising strategy to potentially destabilize ecDNA and sensitize ecDNA-driven tumours to therapeutic intervention.
Cancer genomics, Double-strand DNA breaks
A quadruped robot designed to complete a marathon on a single battery charge
Original Paper | Applied physics | 2026-09-22 20:00 EDT
Choongin Lee, Donghoon Youm, Jeongsoo Park, Jeonghyun Lee, Suyoung Choi, Gwanghyeon Ji, Juhyeok Mun, Moonkyu Jung, Hyungho Chris Choi, Hyeongjun Kim, Hyunsik Oh, Kyungmin Nam, Minho Lee, Jungwoo Hur, Donghyuk Choi, Donggeon Kim, Yeonsu An, Jemin Hwangbo
Recent advances in legged robot control have expanded the potential for quadruped robots in real-world applications, such as rescue operations in disaster zones and mountainous regions1. However, practical deployment is hindered by the limited travel range per battery charge: a challenge compounded by the robots’ inherent structural characteristics. Unlike wheeled robots, quadrupeds continuously expend energy at their joints to support body weight and incur kinetic energy losses during intermittent foot-ground contact. Moreover, optimizing energy consumption is complicated by trade-offs among various physical effects2, necessitating a holistic approach encompassing both hardware and software components. Previous research has predominantly addressed isolated aspects of energy loss3,4,5,6. Here we show RAIBO2, an energy-efficient quadruped developed through a comprehensive analysis of its overall energy-loss model. Efficiency is enhanced through a force-transparent, lightweight mechanical hardware, a low-resistance motor driving circuit and a low-energy-dissipation locomotion policy. RAIBO2 completed a full marathon in 4 hours, 19 minutes and 52 seconds on a single battery charge7, achieving a total cost of transport of 0.25: surpassing the human benchmark of 0.37. Compared with existing quadrupeds, RAIBO2 offers more than three times the travel range per battery charge. This breakthrough in energy efficiency paves the way for extended outdoor applications in which prolonged battery life is critical.
Applied physics, Electrical and electronic engineering, Mechanical engineering
Neuronal detection of social actions directs collective escape behaviour
Original Paper | Animal behaviour | 2026-09-22 20:00 EDT
Jo-Hsien Yu
(游若嫺), Geoff T. Meyerhof, Jimjohn Milan, Julia L. Napoli, Matthew Lovett-Barron
Animals in groups obtain information from social partners to engage in adaptive behaviour1,2,3. Social information transmission is observed in fish schools4,5,6, bird flocks7,8 and human groups9,10, but the neural representation of such socially acquired information is poorly understood3,11,12. Here we show that, in the schooling glassfish Danionella cerebrum13,14,15, collective escape from danger can be mediated by an individual’s visual perception of other escaping animals. To understand the neural basis of socially transmitted escape behaviour, we imaged neural activity from adult glassfish viewing the actions of virtual conspecifics. Visual neurons in the midbrain optic tectum16,17 and thalamus18 increased their activity when virtual conspecifics escaped. Escape-responsive neurons also responded to the sudden disappearance of virtual fish, yet were unaffected by the disappearance of stimuli moving with non-biological linear motion. Behaviourally, fish retreated from virtual schools that escaped or disappeared, but only those swimming with biological burst-and-glide motion. Neural encoding of this rapid social offset allows fish to infer danger from social information alone, a potentially effective strategy for animals that are capable of rapid movement but have a limited visual range14,19. These results show how the neural computations of individuals enable rapid information sharing in collectives.
Animal behaviour, Cooperation, Motion detection, Social behaviour
Organic two-dimensional van der Waals heterostructures
Original Paper | Conjugated polymers | 2026-09-22 20:00 EDT
Anupam Prasoon, Nguyen Ngan Nguyen, Mike Hambsch, Puja Singhvi, Sophia Terres, Zijie Xiao, Naveen Goyal, Haoyuan Qi, David Mücke, Florian Auras, Zhiyong Wang, Sein Chung, Miroslav Položij, Hai I. Wang, Kilwon Cho, Ute Kaiser, Alexey Chernikov, Mischa Bonn, Stefan C. B. Mannsfeld, Thomas Heine, Xinliang Feng
Van der Waals heterostructures based on graphene and inorganic two-dimensional (2D) crystals enable exquisite control of interlayer coupling, and emergent electronic and optical phenomena1,2. Extending this concept to organic 2D crystals has been hindered by weak, non-directional interlayer interactions that frustrate lattice registry. Here we introduce a bottom-up strategy for programmable lattice engineering in organic van der Waals heterostructures of 2D polymers. Sequential on-water-surface assembly enables layer-by-layer stacking of chemically distinct 2D polymers with defined lattice registry, stacking sequence and thickness, yielding both lattice-matched and controlled lattice-mismatched heterostructures. Structural characterization reveals commensurate epitaxy in lattice-matched and small-mismatched systems, whereas large-mismatch interfaces exhibit moiré features and strain-relief distortions. Ultrafast spectroscopy demonstrates efficient interfacial charge separation and first-principles calculations reveal built-in electric fields and interfacial potential steps arising from interfacial dipole alignment. Devices exhibit diode-like rectification ratios exceeding 107 that systematically decrease with increasing lattice mismatch, establishing organic 2D polymer van der Waals heterostructures as a lattice-engineered platform for (opto)electronic and quantum phenomena.
Conjugated polymers, Electronic materials
The mutational dynamics of the Arabidopsis centromeres
Original Paper | Centromeres | 2026-09-22 20:00 EDT
Xiao Dong
(董笑), Wen-Biao Jiao
(焦文标), Lara Goldkuhle, Fernando Rabanal, Samija Amar, Matthew T. Parker, José A. Campoy, Yueqi Tao
(陶玥琪), Bruno Huettel, Jurriaan Ton, Lisa M. Smith, Holger Puchta, Detlef Weigel, Korbinian Schneeberger
Centromeres are essential for faithful chromosome segregation during cell division. Yet despite their conserved function, many centromeres contain highly variable but internally remarkably homogenized tandem-repeat arrays1,2,3,4,5 whose evolutionary dynamics remain poorly understood. Here, using replicated genome assemblies of mutation accumulation lines, we define the centromere-specific mutation spectrum in Arabidopsis thaliana. We find that kilobase-sized insertion-deletion mutations (indels) occur frequently and consistently preserve tandem-repeat arrays by adding or removing only complete repeat units. Point mutations accumulate at an almost tenfold higher rate than elsewhere in the genome, probably driven by non-allelic gene conversion between closely linked repeat units. These findings suggest a central role for homology-directed DNA repair in centromere evolution, further supported by the accumulation of more frequent and longer tandem-repeat-preserving indels in Arabidopsis lines that are deficient in the anti-recombinase helicase RTEL1. Forward-in-time simulations parameterized with the observed mutation spectrum show that kilobase-sized indels and point mutations alone are sufficient to generate the megabase-sized homogenized repeat blocks characteristic of natural centromeres. Together, our results show that centromere evolution is driven by a distinct mutational spectrum shaped by homology-directed DNA repair, providing a quantitative framework for understanding how mutational processes generate and maintain the large-scale architecture of centromeric DNA.
Centromeres, Evolutionary genetics, Genetic variation, Genome informatics, Mutation
Nature Materials
Adsorption-conversion synthesis of ultrathin intermetallics and high-entropy alloys
Original Paper | Synthesis and processing | 2026-09-22 20:00 EDT
Peng Zhang, Feifei Zhao, Xingguo Wang, Haocheng Wang, Kunpeng Si, Yongji Gong, Bixuan Li, Juntian Wei, Yangyu Jia, Binyin Gao, Zheng Liu, Xiaolong Zou, Xiangfeng Duan
Two-dimensional intermetallic compounds (IMCs) and high-entropy metallic alloys (HEMAs) have recently attracted much attention for their emergent physical phenomena. However, the synthesis of two-dimensional single crystals of IMCs and HEMAs represents a considerable challenge due to their intrinsic thermodynamic instability and kinetic uncontrollability. Here we report an adsorption-conversion strategy to synthesize diverse Fe-, Co-, Ni-, Cu- and Pd-based ultrathin single crystals of IMCs and HEMAs, including the compositions that were previously inaccessible. During growth, metal atoms liberated from decomposed surface adsorbates incorporate into the metallic matrix, whereas residue surface Cl atoms kinetically drive the formation of two-dimensional structures by enhancing the energy difference among various facets. The resulting materials exhibit a conductivity of up to 3 × 107 S m-1 and an ultralow temperature coefficient of resistance of 2 ppm K-1. Our work establishes a broad family of ultrathin IMCs and HEMAs as a versatile material platform for exploring emergent physicochemical properties.
Synthesis and processing, Two-dimensional materials
Interlayer hybridization promotes superconductivity in bilayer nickelates
Original Paper | Electronic properties and materials | 2026-09-22 20:00 EDT
Shilong Zhang, Meng Zhang, Qiling Luo, Zihao Tao, Hsiao-Yu Huang, Eugen Weschke, Kunhao Li, Ganesha Channagowdra, Jie Li, Junchi Fu, Di-Jing Huang, Yanwu Xie, Yi Lu, Yingying Peng
Ruddlesden–Popper nickelates offer a route to high-temperature superconductivity beyond cuprates and iron pnictides. However, the electronic reconstruction enabling superconductivity in bilayer nickelates remains unresolved, largely due to the difficulty of directly probing superconducting samples. Here we stabilize superconducting (La,Pr)3Ni2O7 thin films with a protective capping layer, enabling direct X-ray absorption and resonant inelastic X-ray scattering measurements. Across insulating, superconducting and metallic samples, we track the evolution of in-plane and out-of-plane electronic states, spin and orbital excitations, and spin-density-wave order. Combined with theoretical analysis, our results show that itinerant ({d}{ {x}^{2}-{y}^{2}}) states form the in-plane electronic backbone, whereas superconductivity emerges with coherent ({d}{ {z}^{2}})-pz-({d}_{ {z}^{2}}) interlayer hybridization, together with suppressed static spin order and strongly damped spin excitations. Oxygen stoichiometry and epitaxial strain both tune this interlayer channel, placing superconductivity within a narrow regime of interlayer coherence and establishing a multiorbital picture of superconductivity in bilayer nickelates.
Electronic properties and materials, Superconducting properties and materials
Nature Physics
Quantum many-body mixed phase space revealed by hybrid feedback control
Original Paper | Nonlinear phenomena | 2026-09-22 20:00 EDT
Hang Dong, Jie Ren, Andrew Hallam, Han Wang, Zhengyi Cui, Yiren Zou, Junlin Wang, Hekang Li, Qiujiang Guo, Zhen Wang, Lei Ying, Zlatko Papić
Understanding how complex systems transition between order and chaos is a central challenge of non-equilibrium physics. Although weak perturbations of classical integrable systems give rise to a mixed phase space in which regular and chaotic trajectories coexist, analogous behaviour in interacting quantum many-body systems has been difficult to identify. Here we develop and experimentally implement a hybrid quantum-classical feedback protocol that autonomously discovers and stabilizes long-lived regular trajectories in a superconducting quantum processor. Each iteration combines short-time quantum evolution with classical optimization that projects the dynamics back onto a low-entanglement variational manifold, effectively distilling coherence from chaotic evolution. The stabilized trajectories reveal signatures of a quantum many-body mixed phase space emerging from nonlinear variational dynamics, without a direct analogue in few-body quantum systems described by a small number of effective degrees of freedom. Our results establish a framework for the algorithmic identification and control of coherent dynamics in quantum many-body systems.
Nonlinear phenomena, Quantum simulation
String-breaking dynamics in a quantum simulator
Original Paper | Materials science | 2026-09-22 20:00 EDT
Arinjoy De, Alessio Lerose, De Luo, Federica M. Surace, Alexander Schuckert, Elizabeth R. Bennewitz, Brayden Ware, William Morong, Kate S. Collins, Zohreh Davoudi, Alexey V. Gorshkov, Or Katz, Christopher Monroe
In quantum field theory, spontaneous particle formation can occur when the potential energy between two elementary particles increases with their separation, as if they were confined by a string. When the separation exceeds a critical value, new particle pairs can form and the string breaks. Simulating this process ab initio requires solving quantum many-body dynamics of the strong force, a task for which quantum simulators may outperform classical computational methods. Here we probe the spatiotemporally resolved dynamics of string breaking in a (1 + 1)-dimensional ({ {\mathbb{Z}}}_{2}) lattice gauge theory using a programmable trapped-ion quantum simulator. We emulate the effects of external static charges and strings, using site-dependent control of effective magnetic fields through an array of focused laser beams addressing individual ions. We show that isolated charges spread freely in the absence of string tension but exhibit localized coherent oscillations as the tension increases. We further observe the breaking dynamics of a string initially stretched between two static charges following an abrupt increase of the string tension. We find that charge pairs appear near the string edges and subsequently spread out into the bulk, revealing a mechanism for dynamical string breaking distinct from the conventional Schwinger mechanism.
Materials science, Quantum simulation
arXiv
Multimodal Visual Sensing of Temperature and Pressure: From Spectroscopic Readout to Multiple Linear Regression-Enhanced RGB Analysis
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Maja Szymczak, Yufan Meng, Guanjun Xiao, Miguel A. Hernández-Rodríguez, Iga Sawaryn, Bo Zou, Lukasz Marciniak
Transforming a single luminescent host into distinct temperature- and pressure-sensing systems through composition control provides a powerful route toward multifunctional optical sensors. Here, we introduce a concentration-tunable KGaGeO4:Bi3+,Eu3+ platform whose sensing function can be selectively directed toward thermometry or manometry by adjusting the dopant balance. Spectroscopically distinct Bi3+ centers and Eu3+ emission exhibit differentiated responses to temperature and pressure, enabling multimodal readout through ratiometric luminescence, chromaticity coordinates, spectral shifts, and visible color changes. Importantly, these color changes were translated into quantitative temperature and pressure maps using RGB imaging combined with multiple linear regression (MLR). By simultaneously exploiting multiple color channels, MLR increased the maximum relative thermal sensitivity from approximately 1% K-1 for conventional RGB ratios to 8.8% K-1 and the pressure sensitivity from 169% GPa-1 to nearly 721% GPa-1. This work presents the first application of MLR-assisted RGB analysis for quantitative luminescence pressure sensing. The proposed strategy integrates composition-controlled functionality, multimodal spectroscopic sensing, direct visual readout, and data-assisted imaging, demonstrating the synergy between material engineering and multivariate analysis for highly sensitive multifunctional optical sensing.
Materials Science (cond-mat.mtrl-sci)
Thermally Robust and Strongly Pressure-Responsive NIR Luminescent Manometer Based on Cr3+-Ni2+ Emission
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Weijia Xie, Maja Szymczak, Tongxi Luo, Chan Wang, Lukasz Marciniak, Xinguo Zhang
The increasing demand for highly sensitive luminescent manometers capable of precise pressure determination, particularly those operating in the near-infrared (NIR) spectral range, motivates the continuous search for new pressure-responsive luminescent materials. In this work, we introduce NaLu2Ga3Ge2O12:Cr3+, Ni2+ as a highly sensitive NIR luminescent manometer in which pressure not only induces pronounced spectral shifts of the Cr3+ and Ni2+ emission bands but also strongly modulates their relative luminescence intensities. Remarkably, the 3T2(3F)->3A2(3F) emission band of Ni2+ exhibits a record-high absolute pressure sensitivity of SA = 34 nm GPa-1. Furthermore, by appropriately selecting narrow spectral ranges within the pressure-responsive emission bands, a ratiometric NIR luminescent manometer was developed, providing a maximum relative pressure sensitivity of SR = 158% GPa-1. Most importantly, the proposed ratiometric readout exhibits a thermal-invariance manometric factor (TIMF) of 19,900 K GPa-1, which, to the best of our knowledge, is the highest value reported to date for a luminescent manometer. The combination of exceptionally high-pressure sensitivity, NIR operation, and remarkable resistance to thermal interference establishes NaLu2Ga3Ge2O12:Cr3+, Ni2+ as a highly promising luminescent pressure sensor for reliable pressure determination under conditions involving simultaneous temperature variations.
Materials Science (cond-mat.mtrl-sci)
Re-entrant p-wave superconductivity in a Chern Dartboard Insulator
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Yueyang Wu, Rebecca Chan, Taylor L. Hughes, Philip W. Phillips
We formulate an exact theory for a 2-band superconductor with inter-orbital pairing and band Hatsugai-Kohmoto (HK) interactions. We apply this theory to a Chern dartboard insulator and compute the pair susceptibility and pair correlations analytically. We find that in the insulating phase previously predicted by BCS theory (small pairing strength $ g$ , chemical potential $ \mu$ in the gap), the HK interaction can induce superconductivity, and possibly a Chern dartboard superconductor, by lifting the doubly-occupied band and making it cross the chemical potential. From this HK-induced superconductor, we notice that in a significant parameter range (HK interaction strength $ U = 1$ , $ \mu = 0.5$ ), an insulator-superconductor-insulator re-entrant transition exists. We isolate the re-entrance to a conflation between HK interactions and inter-orbital pairings.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
10 pages including supplementary material, 5 figures
Kitaev spin liquid in superconducting networks
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Guilherme Delfino, Mehmet Dede, Dmitry Green, Michael J. Manfra, Charles M. Marcus, Claudio Chamon
We propose a realization of the Kitaev honeycomb Hamiltonian – an archetypal spin-liquid model – in a superconducting metamaterial. The architecture consists of Cooper-pair boxes coupled through depleted semiconductor–superconductor heterostructures that do not require spin–orbit coupling. The Cooper-pair boxes encode effective spin degrees of freedom, while normal and anomalous virtual propagation through the heterostructures mediate bond-directional interactions. Two key control parameters are an out-of-plane magnetic flux and the semiconductor Fermi energy. The former controls interference and distinguishes the bond directions, while tuning the latter close to the bottom of the band gives rise to an emergent Nambu-exchange symmetry that enforces the required bond directionality. Through numerical calculations, we identify an operating regime with controlled corrections, with associated energy and length scales within experimental reach. These results establish a route toward equilibrium quantum spin liquids in engineered superconducting networks.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
9 pages, 7 figures
Scaling of qubit coherence in quantum dot based Majorana chains: Rabi and Ramsey oscillations of Majorana qubits formed by four and six quantum dots
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
We present a theoretical study of the Rabi and Ramsey coherence time of Majorana-based qubits formed by double $ N$ -site quantum-dot artificial Kitaev chains, following the recent experimental realization arXiv:2607.09511. We generalize the qubit to two chains of arbitrary length and compare the Rabi and Ramsey oscillations of the four-dot and six-dot qubits, simulated with realistic disorder for three sets of parameters: small and large superconducting gaps, and the experimental parameters. We find that, in the pristine limit, the Rabi oscillation is independent of the chain length, whereas the Ramsey oscillation of the six-dot qubit suffers from larger leakage, because the third site suppresses the unwanted energy splitting away from the sweet spot but at the same time makes the deliberate splitting difficult to achieve, which requires a larger detuning that could excite the bulk. In reality with disorder, neither coherence time improves universally with the chain length. The Rabi coherence is set by the competition of three dephasing channels, and the additional dots pay off only if the fluctuation of the interchain tunneling is suppressed; the Ramsey coherence is set by the fluctuation of the energy splitting during the $ \sigma_z$ rotation, which for the four-dot qubit is fixed by the sweet-spot disorder alone and does not depend on the mean splitting, whereas for the six-dot qubit the detuning that generates the splitting adds a fluctuation growing with the splitting itself, so the additional dots pay off only for small splittings. This implies that a longer chain is thus a better quantum memory but not necessarily a better qubit under manipulation. Although topological protection is expected in a longer Kitaev chain qubit, observing it in the current Rabi and Ramsey measurement protocols remains an experimental challenge.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
23 pages, 10 figures
Disorder-promoted stability
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-09-23 20:00 EDT
Arthur N. Montanari, Pietro Zanin, Adilson E. Motter
Previous studies of network dynamics have suggested that heterogeneity among nodes inhibits stability, at odds with the ubiquity of inherently heterogeneous natural and engineered systems. Here, we show that this conclusion arises from model reductions introduced for mathematical tractability and breaks down when nodal dynamics are higher-dimensional, yielding non-Hermitian Jacobians. In such systems, including neural, power-grid, and material networks, nodal heterogeneity can instead enhance stability, even when parameters are randomly disordered. Non-Hermiticity also underlies the stabilizing effects of network heterogeneity, which can arise even in one-dimensional nodal dynamics through nonreciprocal interactions, as shown for ecological networks. Our framework reveals disorder not as a liability but as a general resource for stabilizing complex systems.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Dynamical Systems (math.DS), Adaptation and Self-Organizing Systems (nlin.AO)
Science 393, 6817:1241-1249 (2026)
From Effective Temperature to Non-Boltzmann State Selection in Driven-Dissipative Quantum Criticality
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Tiago Jorge, Jens Paaske, Pedro Ribeiro
Whether a nonequilibrium quantum-critical steady state can be described by an effective temperature remains an open question. We address it in a voltage-biased electronic Lipkin–Meshkov–Glick model, a minimal driven-dissipative model of a collective spin coupled to metallic leads. A controlled large-$ N$ treatment reveals an overdamped open quantum-critical regime distinct from the closed model. The surrounding quantum critical fan, organized by temperature and voltage, is explored and fluctuations are found to be governed by an effective temperature $ T_{\rm eff}$ . At strong bias, the transition becomes first-order through a tricritical point. Remarkably, the same $ T_{\rm eff}$ governs the strongly driven regime, but now varies across the entire order-parameter landscape. The steady state is therefore selected by a non-Boltzmann rule, shifting the first-order transition away from the equal-depth point of a deterministic potential. Driven criticality thus remains organized by an effective temperature while revealing non-thermal state selection.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
Extended symmetric quantum phase in a honeycomb Heisenberg model with sublattice-selective interactions
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Nai Chao Hu, Xing-Yu Zhang, Yuchi He, Nick Bultinck
Motivated by two-dimensional bilayer systems we numerically study an anti-ferromagnetic spin-$ 1/2$ Heisenberg model on the honeycomb lattice with a nearest-neighbour exchange coupling $ J_1$ , and a next-nearest-neighbour exchange coupling $ J_2’$ for the B sublattice sites only. Using infinite Projected Entangled-Pair States (iPEPS), variational uniform matrix-product states on cylinders, and exact diagonalization, we find an extended symmetric regime $ 0.4\lesssim J’_2/J_1\lesssim0.6$ , in which local observables show no magnetic, valence-bond, or chiral spin order. At $ J’_2/J_1=0.5$ , the PEPS correlation length grows systematically with bond dimension, and an inverse-correlation-length extrapolation favors a vanishing limit. We also find that various observables scale algebraically with the finite bond-dimension-induced correlation length, which points to a gapless spin liquid ground state. We propose a $ \mathbb{Z}_2$ Dirac spin liquid parton state, with Dirac points that are protected by translation, time-reversal and three-fold rotation symmetry, as a promising candidate state to explain the numerical results. We also discuss the possibility that the symmetric ground state is a featureless, short-range entangled state with a small gap.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
20 pages, 22 figures
Approach to Steady-State in Nested Resetting Processes
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
Callum Britton, Ben Le Jeune, Henry Alston, Paul C. Bressloff, Thibault Bertrand
We characterise the approach to nonequilibrium steady state in nested resetting processes by deriving accumulation times for the system, which quantify the effective first-passage time for the local establishment of steady state. For equal resetting rates, we obtain closed-form expressions showing that relaxation propagates as a wavefront with a delay that increases linearly along the resetting chain. We then extend this analysis to heterogeneous resetting rates, deriving exact steady-state distributions, spatial moments and accumulation times for both degenerate and non-degenerate resetting rates. We show that relaxation to steady state is ultimately governed by the minimum resetting rate in the system and, in degenerate systems, its multiplicity. These results provide a comprehensive analytical description of first-passage to nonequilibrium steady state in hierarchically coupled stochastic resetting systems, with potential applications to relaxation and transport processes in biological systems.
Statistical Mechanics (cond-mat.stat-mech)
41 pages, 10 figures
Order-parameter-dependent mobility in the Convective-Viscous Cahn-Hilliard equation
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
P. O. Mchedlov-Petrosyan, L. N. Davydov, O. A. Osmaev
Generally the mobility in the Cahn-Hilliard equation may depend on the order parameter; this was evident already from the original derivation. However, explicit introduction of such dependence results in tremendous calculation difficulties, so the constant mobility approximation was commonly used. On the other hand, in several cases this dependence appeared to be crucial, so more realistic expressions were applied, usually positive powers or polynomials; still, for such dependencies only approximate and/or numerical solution exist. We consider ‘reciprocal’ linear and quadratic dependencies of mobility on the order parameter; for these dependencies exact traveling wave solutions are obtained. Even more, in a limited interval of the parameters reciprocal quadratic mobilities are rather good approximations to polynomial mobilities.
Statistical Mechanics (cond-mat.stat-mech)
16 pages, 2 figures
Universal behavior in diffuse charge dynamics with patterned electrodes
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
E. Krucker-Velasquez, E. Kirkinis, M. Olvera de la Cruz
Iontronic devices that replicate physiological processes will improve energy efficiency to support artificial-intelligence architectures. Energy storage and conversion devices, however, display disordered interfacial and bulk configurations that conventional impedance spectroscopy cannot resolve. Here, we show that the onset of frequency dispersion in the impedance of an electrolytic cell with non-uniformly charged electrodes takes place at approximately twice the resonator natural frequency, independently of whether the cell is driven by oscillating charges or voltage differences, and remains valid for both overlapping and non-overlapping double layers. In addition to characterizing energy storage devices, these universal findings apply to devices interfaced with biomaterials.
Soft Condensed Matter (cond-mat.soft)
4 pages, 4 figures
Finite-state automata for exact matrix product operators of tight-binding Hamiltonians: fractals, quasicrystals, trees and hyperbolic lattices
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Marta Brzezińska, Jeanne Colbois, Loïc Herviou
Inspired by the recent progress in the simulation of tight-binding Hamiltonians on large lattices using tensor networks, we introduce a systematic matrix product operator (MPO) construction for single-particle Hamiltonians on recursively structured lattices. Taking advantage of this recursive structure, we encode the lattice geometry in a finite-state automaton and, adapting ideas from Abelian-symmetric tensor networks, obtain an exact and analytical MPO representation of the Hamiltonian, where the number of tensors grows logarithmically with the system size and the bond dimension is set by the number of automaton states. Several examples demonstrate the generality of the framework: regular lattices, fractals, Cayley trees, hyperbolic lattices, and one- and two-dimensional Fibonacci quasicrystals. Combined with the kernel polynomial method, these MPO representations enable large-scale calculations of spectral properties without explicitly constructing the full Hamiltonian. This provides a unified route to the exploration of electronic properties across a broad class of lattices at exponentially large system sizes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn), Computational Physics (physics.comp-ph)
16p, 6 figures, comments welcome
Weyl Chirality and Kitaev Topology through Bargmann Invariants
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-23 20:00 EDT
We apply a finite-state geometric formulation based on Bargmann invariants to a two-band Weyl Hamiltonian and the one-dimensional Kitaev model of a p-wave superconductor. For the Weyl system, a symmetry-antisymmetrized third-order Bargmann combination selects the chirality-sensitive component of the local pseudospin geometry and extends to a two-band lattice Weyl model. For the Kitaev chain, a normalized ratio involving a third-order Bargmann invariant and a second-order overlap factor removes the dependence on an intermediate state and reproduces the $ Z_2$ distinction between its two gapped phases. We further construct a fourth-order loop connecting localized Majorana edge-mode profiles with finite-energy BdG states and an alternating fourth-order loop involving opposite Weyl pseudospin sectors. These constructions illustrate how suitable Bargmann combinations can probe chirality-sensitive, topological, and higher-order geometric information directly through quantum-state overlaps, providing an alternative state-based route without requiring a continuous description of the underlying state-space geometry.
Superconductivity (cond-mat.supr-con), Other Condensed Matter (cond-mat.other), Quantum Physics (quant-ph)
12 pages, 0 figures
Thermally melted quadrupolar order and intrinsically quantum phases in 5$d^1$ double perovskites
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Rong Cong, Ginevra Corsale, Ilija K. Nikolov, Wenjuan Zhang, Nandini Trivedi, Vesna F. Mitrović
Spin-orbit-coupled $ d^1$ double perovskites exhibit a rich interplay of spin, orbital, and quadrupolar degrees of freedom (DOF), giving rise to competing magnetic and multipolar phases. Although quantum mean-field theories predict many exotic phases, their stability against thermal fluctuations and reproducibility within a classical framework remain an open question. Here, we surpass the mean-field limitations by deploying large-scale classical Monte Carlo simulations on the projected $ j=3/2$ manifold of the FCC lattice, allowing complex ordering patterns to emerge spontaneously without preassigned magnetic symmetries. Our thermodynamic mapping reveals that thermal fluctuations melt the intermediate-temperature quadrupolar phase over part of the phase diagram, while it survives intact elsewhere. Crucially, by systematically isolating the boundary between classical and quantum stability, we demonstrate that while the four-sublattice antiferromagnetic and ferromagnetic (FM) phases are robustly classical, the coplanar canted FM[110] state completely destabilizes. This identifies the FM[110] phase as an intrinsically quantum state born out of quantum fluctuations. Our results demonstrate that the dominant magnetic phases are robust within a classical description, where the essential physics of the system is captured by weakly entangled, short-range correlated DOF and highlight the role of thermal fluctuations in determining the stability of different types of magnetic and quadrupolar order.
Strongly Correlated Electrons (cond-mat.str-el)
Correlations of Spectroscopic and Dielectric Properties of Hafnia-Zirconia Nanoparticles
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Yuriy O. Zagorodniy, Eugene A. Eliseev, Petr Jiricek, Jana Houdkova, Lesya Demchenko, Oksana V. Leshchenko, Victor N. Pavlikov, Ihor V. Pleskach, Anna O. Diachenko, Mikhail D. Volnyanskii, Oleksandr S. Pylypchuk, Myroslav V. Karpets, Mikhail P. Trubitsyn, Anna N. Morozovska
In this work we analyze correlations of X-ray photoelectron and diffraction spectra, and dielectric properties of hafnia-zirconia nanoparticles (the chemical compositions Hf0.4Zr0.6O2 and Hf0.6Zr0.4O2, and the average size of 7.5 nm) prepared by the solid-state organo-nitrate synthesis and annealed in air. The phase state of the nanoparticles, determined by the X-ray diffraction spectroscopy, is the coexistence of the nonpolar monoclinic (42 - 76 mass %) and orthorhombic (56 - 24 mass %) phases. Concentration of the oxygen vacancies was estimated from the X-ray photoelectron spectroscopy. The increase in the intensity of the dielectric permittivity maximum observed near 350 - 450 K in a PVDF matrix with embedded Hf0.4Zr0.6O2 nanoparticles can be related with an increase in oxygen vacancy concentration. Theoretical calculations, based on Landau-Ginzburg-Devonshire theory, explain the increase of the dielectric permittivity in Hf0.4Zr0.6O2 nanoparticles compared to Hf0.6Zr0.4O2 nanoparticles.
Materials Science (cond-mat.mtrl-sci)
13 pages, 3 figures, To be submitted to the Semiconductor Physics, Optoelectronics and Quantum Electronics
Influence of Electrostatic Environment on the Proximity Spin-Orbit Coupling in Graphene on Transition-Metal Dichalcogenides
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Bert Jorissen, Bart Partoens, Aires Ferreira, Lucian Covaci
We investigate the proximity-induced spin-orbit coupling (SOC) in graphene on transition-metal dichalcogenide (TMD) heterostructures using a tight-binding approach. The tight-binding parameters of an effective 4-band model describing the low-energy physics of the graphene layer are extracted as a function of twist angle, material composition (MoS$ {}_2$ , MoSe$ {}_2$ , WS$ {}_2$ , WSe$ {}_2$ ), band alignment, and charge-transfer dipole. We investigate the effect of a charge-transfer dipole induced on the chalcogen layer closest to graphene, which is typically neglected in tight-binding models but included in ab initio calculations through charge redistribution. In addition, we explore the influence of variations in the band alignment. We find that the spin-valley and Rashba spin-orbit coupling energies as well as the so-called Rashba phase, governing the orientation of momentum-space spin textures, show a strong dependence on the twist angle and electrostatic tuning. Our results suggest that variations in band alignment and charge redistribution contribute to the spread of spin-orbit parameters reported in the literature.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
41 pages, 18 figures
Impact of Chemical Clustering on the Structural, Topological, and Functional Properties of Ba(Zr$x$Ti${1-x}$)O$_3$: An Atomistic Simulation Study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Matias Baldassin, Rodrigo Machado, Marcelo Sepliarsky, Marcelo G. Stachiotti
Barium zirconate titanate, Ba(Zr$ _x$ Ti$ _{1-x}$ )O$ _3$ (BZT), is a leading lead-free candidate for high-performance electronic components due to its highly tunable ferroelectric-to-relaxor transition. In this study, we employ molecular dynamics simulations to investigate the effects of local chemical clustering on the structural and functional properties of BZT in both ferroelectric (x = 0.2) and relaxor (x = 0.4) regimes. Crucially, we demonstrate that Zr clustering induces a significant enhancement of local polarization across both compositions. Rather than a purely volume-driven effect, this enhancement is fundamentally governed by a spatial redistribution of local structural phases (rhombohedral, orthorhombic, and tetragonal); Zr segregation forms larger, continuous Ti-rich regions that expand highly polar rhombohedral domains and foster cooperative dipolar alignment. This cooperative coupling thermally stabilizes the local polar order, systematically elevating the Curie, maximum permittivity, and Burns temperatures. Focusing on the relaxor composition (x = 0.4), chemical segregation promotes the formation of resilient, swirling polar topological textures,categorized into vortices circulating around Zr-rich clusters and interstitial vortices localized within the Ti-rich matrix. These topological structures act as effective pinning barriers against polarization reversal, driving pronounced electrical hardening with elevated coercive fields. Ultimately, these findings establish a quantitative link between nanoscale compositional heterogeneity, polar domain topology, and macroscopic performance, providing a robust framework for engineering lead-free perovskites via local chemical order control.
Materials Science (cond-mat.mtrl-sci)
Accepted for publication in Materials Today Physics
Nanoscale Sr$_2$IrO$_4$ Freestanding Thin-Films for Flexible Electronics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Sujan Shrestha, Matthew Coile, Menglin Zhu, Maryam Souri, Jiwoong Kim, Rina Pandey, Joseph Brill, Jinwoo Hwang, Jong-Woo Kim, Ambrose Seo
We report the structural and optical properties of nanoscale Sr2IrO4 freestanding thin-films fabricated using a water-soluble Sr3Al2O6 layer. The coherent lattice structure, phonon modes, two-magnon Raman scattering, and optical absorption spectra of the Sr2IrO4 nanomembrane are analogous to those of the layered iridate epitaxial thin-films and single crystals. Remarkably, the formation of 3-unit-cell-thick SrIrO3 and interfacial composite layers alleviates antiphase boundaries at the Sr2IrO4/Sr3Al2O6 interface, resulting in structurally-robust nanomembranes. Our experimental results show that this freestanding thin-film approach of layered oxides can provide techniques for tuning or realizing unprecedented states beyond conventional thin-film methods, suggesting a pathway in achieving flexible layered-oxide electronics.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 4 figures
ACS Applied Nano Materials 3, 6310 (2020)
Comment on “Andreev Reflection to Probe Momentum-Dependent Spin Polarization in Altermagnet CrSb”
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-23 20:00 EDT
Igor I. Mazin, Maxim Khodas, Boris Nadgorny
Zhang et al. [Phys. Rev. Lett. 137, 016701 (2026)] report momentum-dependent spin polarization in the altermagnet CrSb from point-contact Andreev reflection along the (0001), (-1-120), and (10-10) directions. We show that the Andreev spin polarization they claim to measure is forbidden by symmetry: it vanishes identically in the diffusive regime for all directions in CrSb, and in the ballistic regime for two of the three orientations measured. It is allowed only along one direction, where the calculated band structure gives ~50%. The large, nearly isotropic values reported follow from an incorrect definition of ballistic Andreev spin polarization that evaluates the spin asymmetry at fixed three-dimensional momentum; the Andreev selection rule is local only in the momentum component parallel to the interface. Moreover, the ballistic regime is not demonstrated, and the fitting procedure is flawed.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
2 pages, 1 figure, Comment on arXiv:2606.13395
Lattice in Line: Optimized DMRG ordering for complex lattice geometries
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
The density-matrix renormalization group (DMRG) is a one-dimensional tensor-network technique, but it is not limited to one-dimensional systems: it can be applied to periodic 2D and 3D clusters and molecules, provided their sites are first enumerated along a line; a step one may call “lattice compilation”.
This paper discusses three proxy loss functions for finding this optimal enumeration: the graph bandwidth $ B$ (maximum interaction range), the cutwidth $ C$ (maximum number of bonds crossing a cut), and the average interaction range $ R$ . Constructing the Hamiltonian MPO (matrix-product operator) for a large set of clusters that are of interest in frustrated magnetism, I find that $ C$ determines the peak SU(2) Heisenberg MPO bond dimension and $ R$ the average one. Targeting $ (C,R)$ lexicographically yields the best energies. Targeting $ B$ indirectly reduces $ C$ , but not as efficiently as targeting $ C$ directly. Otherwise, the value of $ B$ itself is largely irrelevant in the sense that good DMRG energies can have large $ B$ .
To perform the optimization, classic heuristics (e.g. reverse Cuthill–McKee) prove unreliable even for small clusters, and I find that a QUBO formulation improves them only marginally. Instead I propose a staged optimization built on Boolean satisfiability (SAT) and constraint-programming (CP) solvers, chiefly CP-SAT of Google’s OR-Tools, a hybrid of CP propagation and SAT clause learning. This approach yields significantly better orderings together with rigorous bounds.
The corresponding Lattice in Line code is available at this https URL and was designed with extensive use of the Fable 5 large language model.
Strongly Correlated Electrons (cond-mat.str-el)
Self-limited stacking of non-Euclidean colloidal shells: From saddles to caps
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Kyle T. Sullivan, Mark J. Stevens, Gregory M. Grason
The presence of geometric frustration in self-assemblies, stemming from a shape misfit between identical subunits, can lead to the spontaneous formation of finite-sized structures known as self-limitation. Recently proposed models of curved, colloidal shells, dubbed “curvamers”, that form one-dimensional stacks have shown curvature-induced frustration to be a promising class of particle designs for engineering self-limiting assembly. However, existing models of curvamer assembly considered only cylindrically curved shells where elastic costs are derived purely from bending. Here, we study the self-limiting behavior of a more general class of curvature-frustrated colloidal shells, extending shapes to include non-Euclidean geometries such as spherical caps and saddles whose deformations can also incur stretching costs. We introduce continuum mechanical and discrete, coarse-grained models of shell stacks to study how qualitatively different intra-assembly strain gradients required for each geometry affect the buildup of super-extensive elastic costs. We find the accumulation of elastic energies in non-Euclidean shell stacks is sensitive to shell thickness via a dimensionless quantity related to the Foppl-von Karman number that characterizes the relative strength of stretching to bending. In particular, thin shells penalize stretching more causing faster elastic energy growth resulting in the suppression of self-limitation with sizes generally largest for cylindrical shells, smallest for spherical caps and intermediate for saddles. We additionally find that while thin spherical caps experience the strongest elastic penalties, the rapidly increasing rate of elastic penalties in stacks of saddles lead to a robust size-selection as inter-particle binding strength grows as well as relatively smaller dispersity in self-limiting stack size in comparison to cylindrical and spherical curvamers.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
27 pages, 11 figures, 5 appendices
Statistical signatures of microorganism motility under environmental stress
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Luiza Treichel Mossi, Nicole Mazzitelli Narvaz, Larissa da Silva Bento, Roger Modena, Bernardo Boatini, Amalia Garcez, Leonardo Gregory Brunnet, Alexandre Arenzon, Carolina Brito
The motility of microorganisms provides a natural framework for studying active matter and its response to environmental perturbations. We experimentally investigate the trajectories of \textit{Paramecium caudatum} and \textit{Artemia salina} under controlled conditions. Using video microscopy, we reconstruct individual trajectories over time. Beyond baseline conditions, we analyze stressed environments where \textit{P. caudatum} are exposed to a toxic agent and \textit{A. salina} are placed in distilled water. To characterize the motion, we compute trajectory-based metrics, including mean square displacement, velocity distributions, persistence times, tortuosity, and radius of gyration. These observables quantify changes in motility patterns across species and conditions. To interpret the dynamics, we develop coarse-grained stochastic models parameterized directly from experimental data. \textit{P. caudatum} is described within a run-and-tumble framework, including reversal events under stress. In contrast, \textit{A. salina} requires a run-and-tumble-like description with persistent orientational noise, accounting for continuous directional fluctuations during runs. The models reproduce the main trajectory-level observables used for comparison, namely tortuosity and radius of gyration. This combined approach provides insight into how environmental stress modifies locomotion statistics. Our results highlight systematic differences in the statistical signatures of motion, suggesting that trajectory metrics may serve as indicators of physiological stress. This work provides an accessible framework for active matter experiments where individual-level statistics can be directly measured and modeled.
Soft Condensed Matter (cond-mat.soft)
Accepted for publication in Soft Matter
Soft Matter (2026)
Observation of the magnetic spin Hall effect in a ferromagnet
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Nicholas Davey-García, Jone Mencos, Luciano Bravo, Inge Groen, Luis E. Hueso, Andreas Berger, Fèlix Casanova
The conventional spin Hall effect generates spin currents whose flow direction, spin polarization, and driving electric field are mutually perpendicular. Magnetic order lifts this symmetry restriction and enables additional time-reversal-symmetry-odd components of the spin-conductivity tensor, giving rise to the magnetic spin Hall effect (MSHE). These components also couple the generated spin polarization to the magnetic order, providing a degree of control absent in the conventional spin Hall effect. Although the MSHE has been observed in antiferromagnets, its experimental identification in conventional ferromagnets has remained elusive. Here, using a non-local lateral spin-valve geometry, we electrically identify the MSHE and its reciprocal effect in a perpendicularly magnetized Co-based multilayer. Reversal of the multilayer magnetization reverses the MSHE and magnetic inverse spin Hall signals, revealing their time-reversal-symmetry-odd character and magnetization control. By contrast, the conventional spin Hall and inverse spin Hall signals measured in the same devices remain unchanged under magnetization reversal, consistent with their time-reversal-symmetry-even character. We obtain a magnetic spin Hall angle of $ \theta_{\mathrm{MSH}} = (3.8 \pm 0.6)%$ , comparable in magnitude to the spin Hall angle of heavy metals commonly used in spintronic devices, such as Pt. These results establish the MSHE as a sizable, magnetically switchable spin-charge interconversion mechanism in conventional ferromagnets.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
10 pages, 4 figures, and Supplementary information
Coherent lattice dynamics distinguish Holstein and Su-Schrieffer-Heeger electron-phonon coupling
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Debshikha Banerjee, Jinu Thomas, G. Alvarez, T. P. Devereaux, T. A. Maier, S. Johnston
Ultrafast pump-probe spectroscopy provides a powerful means to investigate electron-phonon (e-ph) interactions in strongly correlated systems. Nevertheless, the question of how different microscopic e-ph coupling mechanisms influence the lattice’s nonequilibrium response has not been widely addressed. We perform time-dependent density matrix renormalization group simulations on a pumped one-dimensional Mott insulator coupled to phonons through either Holstein or Su-Schrieffer-Heeger (SSH) interactions. The electronic responses of the two models are qualitatively similar in the Mott-insulating regime and are governed by the same excitations and resonance conditions of the Hubbard model. In contrast, the lattice dynamics of the two models differ substantially. While the Hubbard-Holstein model exhibits long-lived coherent phonon oscillations when the pump resonates with the bare phonon frequency, no such oscillations are observed for the Hubbard-SSH model. These contrasting responses remain robust against changes in phonon frequency and pump parameters, suggesting that coherent lattice dynamics can provide a direct nonequilibrium probe of the microscopic form of e-ph coupling.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 10 figures
Ultrafast Dissipative Localization of Electronic Energy in AuPt Superlattices
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
C. Walz, M. Mattern, J.-E. Pudell, J. Jarecki, L. Mehner, F.-C. Weber, F. Baltrusch, S. P. Zeuschner, M. Herzog, B. Ahn, J. C. Ekström, D. Kroon, A. Jurgilaitis, J. Larsson, M. Kronseder, D. Schick, A. von Reppert, M. Bargheer
Controlling the spatial distribution of absorbed optical energy is central to nanoscale photothermal chemistry, plasmonics, and ultrafast materials control. Here, we show that a metallic AuPt superlattice concentrates electronic energy in Pt within a few hundred femtoseconds, regardless of the initial energy distribution between the two constituents. Ultrafast X-ray diffraction follows this energy redistribution through the amplitude of a coherent 570 GHz superlattice phonon driven by the stress imbalance at the AuPt interfaces. Despite the nearly homogeneous absorption at 400 nm, the observed lattice motion is identical to that produced by 800 nm excitation, which is absorbed predominantly in Pt. This dissipation driven localization of energy arises from the large electronic heat capacity of Pt and rapid electronic transport through the superlattice, providing a route to femtosecond control of nanoscale energy distributions.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
8 pages, 4 figures
On Energy References when a Magnetic Field is Applied. A Practical Guide to Reference Energies with and without a Magnetic Field
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
We present a simple analysis of the energy references and of the magnetic-field-dependent and system-dependent features of the Landau energy levels. The energy reference used in describing Landau quantization is usually taken as given, with the Fermi levels of the electron system and the coupled reservoir aligned in thermal equilibrium. Nevertheless, the dependence of the Landau-level spectrum on magnetic field can make the relation between these energy references less transparent. In this work, we show that when a magnetic field is applied and the confined Landau levels $ E_n$ are established, both the Fermi level $ E_F$ and the bottom energy $ E_0$ remain fixed when the magnetic field varies. We show that the bottom energy $ E_0$ is independent of $ B$ , and determined by a system-dependent field $ B_1$ , defined by the condition that the first Landau level equals the Fermi energy. In contrast, the minimum of the parabolic well depends explicitly on the magnetic field. The resulting picture provides a simple way of displaying the relative motion of the Landau levels and the fixed Fermi level without introducing a magnetic-field-dependent energy zero.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
one figure
Efficiency of Continuous-Time Quantum Monte Carlo Updates in the Ferromagnetic State of the Doped SU(3) Fermi-Hubbard Model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Juntaro Fujii, Kazuki Yamamoto, Akihisa Koga
We investigate the sampling efficiency in a segment-based continuous-time hybridization-expansion quantum Monte Carlo solver within dynamical mean-field theory for the doped SU(3) Fermi-Hubbard model. Focusing on the low-temperature and strong-coupling regime, where a ferromagnetic state appears upon hole doping away from one-third filling, we compare several update schemes. Adding the double-flip update to the basic local update yields the smallest integrated autocorrelation time of the majority-flavor occupation in the ferromagnetic regime, whereas adding the flavor-permutation update is the most effective in the paramagnetic regime. We further clarify the origin of this difference by analyzing the characteristic occupation changes caused by accepted updates.
Strongly Correlated Electrons (cond-mat.str-el)
6 pages, 3 figures
Kinetic Interference in Translational Control: A Path-Measure Framework for Collision-Triggered Transcript Decay
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
I connect two literatures developed independently: the path-measure formulation of non-equilibrium statistical mechanics, where a trajectory action decomposes into a time-antisymmetric (entropic) and time-symmetric (frenetic) sector, and the stochastic modelling of ribosomal traffic on messenger RNA. The biological target is a proposed intervention – antisense oligonucleotide (ASO) interference with wobble-uridine (U34) modification of transfer RNA – whose intended effect is not to abolish translation but to perturb its timing, driving ribosome collisions and collision-triggered transcript decay preferentially on high-flux, codon-biased transcripts.
Dynamical-activity and large-deviation analyses of generic lattice exclusion models – notably the symmetric and totally asymmetric simple exclusion processes – are well established. To my knowledge their formalization specifically for ribosomal traffic queues, translation elongation, and collision-triggered no-go decay remains unoccupied; this paper addresses that narrower gap, not the general one.
Two claims here are load-bearing and untested. First, selectivity: transcripts whose loss is therapeutically desirable are separable, by vulnerable-codon-pair burden, from transcripts whose loss is toxic. Second, non-redundancy: the frenetic decomposition yields predictions, specific to ribosomal queueing and collision-triggered decay, not already obtainable from rate-level exclusion-process models or existing activity/large-deviation analyses of exclusion processes. This paper establishes neither. It specifies both as falsifiable tests with pre-registered decision rules, including outcomes under which the framework should be abandoned or narrowed. It is a research programme proposal, not a result. No new experimental, computational, or bioinformatic results are reported.
Statistical Mechanics (cond-mat.stat-mech)
7 pages, no figures
5DSTEM of Liquid-Phase Nanocrystal Growth Bridges Ensemble Kinetics and Nanoscale Dynamics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Serin Lee, Colin Ophus, Jennifer Dionne
Resolving how ensemble growth kinetics emerge from particle- and grain-level dynamics is essential for predictive control of nanocrystal synthesis. Here, time-resolved four-dimensional scanning transmission electron microscopy (4DSTEM), extended into five dimensions (5DSTEM) through continuous acquisition, is used to simultaneously resolve morphology, crystallographic orientation, and lattice strain during Au nanocrystal growth in aqueous HAuCl4. Although ensemble growth follows surface-reaction-limited kinetics, individual nanoparticles exhibit distinct pathways, including continuous growth and discrete coalescence through oriented attachment. These pathways display characteristic orientation dynamics, with stable or gradually selected orientations during continuous growth and abrupt reconfiguration followed by alignment during coalescence. At the ensemble level, the out-of-plane orientation distribution is established early and remains stable, whereas in-plane orientations remain broadly distributed without global alignment. Tensile strain develops progressively from particle surfaces and interfaces, directly linking lattice distortion with evolving morphology and crystallographic structure. By connecting ensemble kinetics with particle- and grain-resolved structural evolution, 5DSTEM provides a general framework for uncovering heterogeneous growth mechanisms and for relating synthesis pathways to structure-dependent properties in functional nanomaterials.
Materials Science (cond-mat.mtrl-sci)
Model Fractional Quantum Hall States on Lattices: Exact Parent Hamiltonians and Routes to Realization
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Recent advances in engineered quantum platforms have enabled the realization of bosonic Laughlin states at $ \nu=1/2$ and brought non-Abelian topological phases within experimental reach. A central theoretical challenge is to develop a unified framework connecting lattice fractional quantum Hall (FQH) model states, exact parent Hamiltonians, and experimentally accessible interactions. We systematically construct Hermitian parent Hamiltonians for which continuum lowest Landau level (LLL) model states sampled on lattice sites are exact zero modes. Using these model manifolds as quantitative references, we find that, within the projected lattice LLL at the flux densities studied, short-range density interactions stabilize Laughlin ground-state manifolds at $ \nu=1/3$ and $ 1/4$ , while two-body onsite repulsion supports a Moore–Read triplet at $ \nu=1$ . Full multiband calculations reveal a sharp contrast: the Laughlin manifolds remain robust against interband mixing on the studied tori, whereas the Moore–Read triplet becomes less spectrally isolated and eventually undergoes a level crossing with competing states near the interband scale. Our framework provides a theoretical foundation for using lattice model states to guide the search for experimentally accessible Abelian and non-Abelian FQH states.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas)
17 pages, 10 figures; includes Supplemental Material
Scaling behavior of eigenspectrum for entanglement from correlation matrices
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
We study the scaling behavior of the eigenvalues of correlation matrices, which characterize the entanglement of a subsystem with its complement part of a total pure state. A most distinguishing feature of entanglement entropy is its logarithmic dependence on the subsystem size for the groundstate of one-dimensional critical systems. Despite its robust universal character and relevance to a wide range of topics, a thorough understanding of this result requires sophisticated mathematical physics techniques or conformal field theory. The aim of our work is to shed light on this from the underlying eigenvalue distribution perspective. The central object is the correlation matrix, which takes the form of Toeplitz or block-Toeplitz matrix. We develop a circulant matrix approximation in the large matrix dimension limit, thus allowing for the individual eigenvalues behavior to be analysed analytically. We find that for both free lattice fermions and transverse field Ising chain, eigenvalues in the bulk of the eigenspectrum scales as $ 1/L_A$ with the subsystem size. Together with the extensivity of the entropy function, it explains the robust $ \log_2 L_A$ scaling of entanglement at criticality. Perturbing from the entanglement-free limit of the Ising chain, we find a smooth crossover behavior to `non-critical’ scaling that is characterized by a very slow logarithmic dependence rendering it seemingly a constant entanglement value expected of non-critical systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 5 figures
Realization of quantum spin Hall insulator superlattice with emergent multigap-like helical edge states
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Hui Guo, Xianghe Han, Fang Qin, Xiaoshuai Fu, Hao Peng, Hongqin Xiao, Hengxin Tan, Chen Liu, Zihao Huang, Jiayi Wang, Qian Fang, Rui Chen, Haitao Yang, Wang Yao, Li Huang, Hai-Zhou Lu, Hui Chen, Hong-Jun Gao
The functional quantum spin Hall insulators (QSHI), protected by time-reversal symmetry against single-particle backscattering, hold great promise for dissipationless quantum electronics. Realization of QSHI with gapped helical edge states, which would enable deterministic on/off switching of the edge-channel conductance, is a key requirement for programmable topological circuits. Here, we report realization of superlattice-modulated QSHI HfTe5 hosting emergent multigap-like helical edge states. Using scanning tunneling microscopy and spectroscopy, we identify a reconstruction-induced periodic superlattice modulation in epitaxial monolayer HfTe5 and directly observe multiple gap-like features in the edge channel, accompanied by a series of sharp peaks in the density of states. Combined with theoretical modelling, we attribute the observed edge gap to the finite-width coupling between the two edges significantly enhanced by the superlattice modulation, whereas the sharp peaks are the manifestations of mini-gaps opening at the reduced Brillouin zone boundaries by the periodic modulation of spin-orbit coupling. Notably, these sharp peaks exhibit clear Zeeman splitting under magnetic fields, consistent with the helical nature of the topological edge states. Our results establish a viable route to engineering gapped helical edge states in QSHI and provide a promising platform for topological devices with desired on/off switchability.
Materials Science (cond-mat.mtrl-sci)
24 pages, 4 figures
Analysis of Josephson junctions switching time distributions for the detection of single microwave photons
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-23 20:00 EDT
A. S. Piedjou Komnang, C. Guarcello, C. Barone, C. Gatti, S. Pagano, Vincenzo Pierro, A. Rettaroli, G. Filatrella
We investigate an optimal scheme for the detection of single microwave photons by a Josephson junction through the analysis of its switching times distribution. The proposed analysis is of support for the decision about the existence of the photon field, which is important in the case of rare events. We assume that the cavity and the transmission line are ideal (each photon absorbed to the cavity gives a current pulse as the output of the transmission line) and the photon source is periodic. The employed methodology consists in comparing the switching probabilities of a Josephson junction exposed to a train of current pulses, simulating a weak photon field, with that of the same device in absence of pulses. In both cases, thermal noise can induce thermal activated switchings. The investigation of the unbalance in the number of switching events in the two cases, gives an estimate of the efficiency of the detection. Furthermore, in the assumption of escapes described by Kramers model, it is possible to provide a relationship between the properties of the photons field, the quantum efficiency of the detection process, and the Josephson junctions switching features at finite temperatures.
Superconductivity (cond-mat.supr-con)
Chaos, Solitons and Fractals 142 (2021) 110496
Strong coupling polarons in cavity quantum materials: limits of cavity-induced electron mass renormalization
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Cavity-induced electron mass renormalization is an important ingredient of many proposals to control material properties through vacuum field modification. What is its ultimate limit? Here this question is answered by (i)noting that this mass renormalization is essentially due to the field-mediated interaction between the electron and the polarizable degrees of freedom in the cavity mirrors, and (ii)directly evaluating the corresponding Feynman path integral for a 2D electron by numerically exact quantum Monte Carlo. The sought upper limit is provided by the Landau-Pekar polaron in the planar geometry. The presented calculation bridges the gap between cavity control and dielectric engineering of material properties.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 6 figures
Nullspace-guided Adaptive Bootstrap of Quantum Many-body Systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
We introduce a nullspace-guided adaptive (NGA) bootstrap method that improves the energy lower bounds of quantum many-body ground states by refining the bootstrap basis in a dynamic and incremental way. At each iteration, the optimized moment matrix reveals a nullspace of saturated positivity directions, which is intuitively interpreted as annihilators of the approximate ground-state subspace. The NGA bootstrap then prunes operators with small nullspace leverage and grows the basis along descendants of these null directions. By applying the NGA bootstrap to the transverse-field Ising chain, we obtain nearly exact energy lower bounds because the algorithm automatically discovers the eigenoperator structure in terms of Jordan-Wigner fermions from a minimal local bootstrap basis. For the Hubbard chain, it improves upon state-of-the-art energy lower bounds by up to two orders of magnitude, reaching errors ranging from $ 10^{-3}$ down to $ 10^{-5}$ in the strongly correlated regimes. We further show that the NGA framework can be used to improve the certified two-sided bounds on general observables. In addition, the bootstrap error decreases approximately as a power law with increasing computational resources. These results suggest that our method provides a practical and scalable route toward accurate bootstrap of general quantum many-body systems.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
13 pages, 5 figures
Cryogenic Voltage Control of Magnetism in Silicon-Integrated \newline SrTiO$_3$/Fe Heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Stijn Reniers, Emile Fourneau, Andries Boelen, Xing-Jian Liu, Ekaterina Gorokh, Lukas Nulens, Vivek Kumar, Luca Ceccon, Christian Haffner, Clement Merckling, Jun-Yi Ge, Bertrand Dupé, Alejandro V. Silhanek, Kristiaan Temst, Joris Van de Vondel
Cryogenic electronics forms a rapidly emerging research domain for high-performance and power-efficient computing applications. Incorporating nanomagnetic components in cryogenic circuitry adds highly valuable functionality, facilitating downscaling, reducing energy consumption and introducing time-reversal symmetry breaking. Furthermore, low-temperature environments enhance magnetic stability and switching efficiency at nanoscale dimensions, reinforcing the potential of cryogenic nanomagnets. To fully leverage these opportunities, magnetic control schemes require alternative options to current-based writing, which is the main bottleneck regarding power consumption and downscaling. In this regard, voltage-based gating of the magnetic state could drastically enhance operational efficiency and integration density. In this work, we investigate cryogenic Voltage Control of Magnetism (VCM) in epitaxial SrTiO$ _3$ /Fe thin film heterostructures on a CMOS compatible Si substrate. We demonstrate and quantify voltage-controlled modifications of the magnetic domain structure, consistent with electric field-controlled magnetic anisotropy at the Fe/SrTiO$ _3$ interface. These findings provide a viable material system for the development of next-generation magnetic domain-based devices for classical and quantum computing.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Measure-zero delocalization in the complex plane: exact mobility arcs in a non-Hermitian off-diagonal quasiperiodic lattice
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-09-23 20:00 EDT
We investigate Anderson localization in a one-dimensional lattice with non-Hermitian off-diagonal quasiperiodic disorder, extending a recently studied Hermitian mosaic model to the non-Hermitian regime. Using Avila’s global theory, we derive the exact Lyapunov exponent and the complete phase diagram in the complex energy plane. This work contains two central findings. First, we discover mobility arcs—open curved segments in the complex plane—as a new class of mobility edges and the generic form of open mobility edges, which coexist with closed mobility rings in a complementary parameter regime. These arcs share the same localization physics as the previously reported mobility lines: eigenstates are delocalized if and only if their energies lie exactly on these sets; any deviation yields localized states. This constitutes a striking measure-zero delocalization phenomenon: delocalized states occupy only zero-measure sets (arcs or lines) in the complex plane, in sharp contrast to the mobility rings, which enclose a finite-area region of delocalized states. Second, we reveal that mobility rings, arcs, and lines all share a common mathematical origin in the generalized Joukowski transformation $ P(E) = \frac{1}{2}(u - w^2/u)$ , rooted in the algebraic structure of the underlying polynomial: the preimage of the boundary of an elliptical region under the polynomial map $ P(E)$ gives the rings, while the branch cut inside this ellipse gives rise to the mobility arcs and lines in the complementary parameter regime.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Other Condensed Matter (cond-mat.other), Quantum Gases (cond-mat.quant-gas)
13 pages, 9 figures
Different reconstruction pathways toward superconductivity in TaRhTe4 and TaIrTe4 Weyl semimetals
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-23 20:00 EDT
Jinyu Zhao, Yang Fu, Congcong Le, Shuaihang Sun, Shu Cai, Yang Ding, Qi Wu, Hechang Lei, Jiangping Hu, Lili Zhang, Cedomir Petrovic, Liling Sun
Pressure can drive Weyl semimetals toward superconductivity through qualitatively distinct reconstructions of their lattices and normal-state electronic structures. Here, we report the first observation of superconductivity in compressed TaRhTe4. This finding enables a direct comparison of the distinct reconstruction pathways leading to superconductivity in TaRhTe4 and the previously studied TaIrTe4, both of which belong to the TaXTe4 (X = Rh, Ir) family of type-II Weyl semimetals. For TaRhTe4, high-pressure electrical-resistance, Hall effect, and magnetoresistance measurements, together with synchrotron X-ray diffraction and first-principles calculations, reveal a superconducting transition that emerges near 20 GPa, with onset Tc increasing to approximately 2.6 K at 65.2 GPa and zero resistance achieved above 63 GPa. The onset of superconductivity coincides with a progressive lattice distortion, a strong suppression of the positive magnetoresistance, and a continuous decrease of the Hall coefficient toward zero. Calculations further show that additional electron-like bands cross the Fermi level (EF) and that N(EF) increases upon compression. This evolution contrasts with TaIrTe4, where the Hall coefficient initially increases before reversing its pressure dependence near the superconducting threshold, while the structural anomaly is confined to a narrower pressure interval. This comparison indicates that superconductivity in the TaXTe4 family is not tied to a unique critical pressure or a single Fermi-surface reconstruction, but can emerge through distinct material-specific pathways once pressure sufficiently reconstructs the low-carrier Weyl-semimetal-derived state into a multiband metallic regime.
Superconductivity (cond-mat.supr-con)
17 pages, 4 figures
Time-reversal-odd Transport in Odd-Parity Magnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Ling Bai, Si Li, Libor Šmejkal, Yugui Yao, Wanxiang Feng
Unconventional magnets combining vanishing net magnetization with spin-split electronic structures and anomalous transport have attracted considerable attention. Using spin-group symmetry analysis, we derive general conditions for odd-parity spin splitting in two- and three-dimensional coplanar noncollinear antiferromagnets. We identify a key spin-group symmetry whose relativistic counterpart forbids time-reversal-odd transport and show that breaking it allows such transport in the presence of spin-orbit coupling. Tight-binding calculations validate these symmetry arguments and demonstrate an anomalous Hall effect in a fully compensated odd-parity magnetic state without an external field. By screening a three-dimensional magnetic materials database and constructing two-dimensional heterostructures, we further identify realistic platforms exhibiting pronounced spin-orientation-dependent anomalous Hall and magneto-optical effects. Our results establish a general symmetry framework for time-reversal-odd responses in odd-parity magnets and highlight fully compensated odd-parity magnets as a promising platform for controlling anomalous transport.
Materials Science (cond-mat.mtrl-sci)
main text: 7 pages, 3 figures
Fractional Quantum Geometry in Topological Mott Regime
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Junyu Tang, Hongquan Lv, Gang v. Chen
Inspired by recent interests in quantum geometry in electronic bands, we consider a two-dimensional topological Mott insulator, i.e. chiral spin liquid, whose spinon bands develop nontrivial band topological and quantum geometry. The virtual polarization of the gapped charge sector transfers the electromagnetic drive to the charge-neutral spinons through the emergent U(1) gauge field, producing a tensor Ioffe-Larkin response and enabling two complementary optical protocols for measurements. In the off-shell (low-frequency) regime, a self-calibrated ratio of the physical longitudinal and Hall conductivities yields the spinon Chern number without the microscopic knowledge of the charge response. In the on-shell (resonant) regime, combining the inverse Ioffe-Larkin response with the Kramers-Kronig relation enables reconstruction of the quantum-metric and Berry-curvature spectral densities. Our approach directly applies to the triangular lattice Hofstadter-Hubbard model in Moiré systems, can be well adapted to other triangular lattice antiferromagnets such as Nb$ _3$ Br$ _8$ with appropriate modifications. We establish a unified framework for quantitatively probing the quantum geometry of fractionalized quasiparticles in topological Mott regime.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Thermodynamic efficiency of communication channels
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
Nahuel Freitas, Pedro E. Harunari, Massimiliano Esposito
We identify a broad class of communication channels that captures common physical constraints in both artificial and natural systems and derive bounds on their thermodynamic cost. We find that the entropy production per channel use is bounded from below by the input-output mutual information, and their ratio -mutual information divided by entropy production- defines the thermodynamic efficiency. Unlike previous studies of energy-constrained communication channels, our analysis shows that thermodynamic costs must be assigned not only to the input symbols themselves, but also to transitions between successive symbols. As a result, maximizing thermodynamic efficiency favors a biased input that switches only rarely, rather than the capacity-achieving input. For the binary symmetric channel, this preference emerges through a pitchfork bifurcation that spontaneously breaks the symmetry of the channel. A minimal model of cellular sensing exhibits the same phenomenon.
Statistical Mechanics (cond-mat.stat-mech)
Ab initio study of magnetic Cu$_2$Sb compounds related to antiferromagnetic CuMnAs
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Vojtěch Pařízek, Jakub Železný
The antiferromagnetic metal CuMnAs has become a workhorse of antiferromagnetic spintronics. A broad range of phenomena has been demonstrated in this material, most notably current-induced switching and heat-driven quench switching, both first realized in CuMnAs. CuMnAs belongs to a much larger family of intermetallic compounds sharing the tetragonal Cu$ _2$ Sb-type structure, yet the magnetic properties of most of its members, and their potential for spintronics, have not been studied. Here we report a systematic density functional theory (DFT) study of the magnetic and electronic structure of more than 50 compounds of this family, intended to guide future theoretical and experimental work toward spintronic applications. We find a wide range of magnetic ground states, among them over 20 new antiferromagnetic candidates.
Materials Science (cond-mat.mtrl-sci)
Intersection Exponents of Simple Random Walks in Two and Three Dimensions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
Qiyuan Shi, Runsheng Liu, Xinyi Li, Ming Li, Youjin Deng
The probability that several independent random walks avoid one another decays algebraically with the number of steps $ N\to\infty$ in two and three dimensions, $ P_N\sim N^{-\xi/2}$ , where the intersection exponent $ \xi$ depends on the number of random walks. More generally, one may consider several groups of independent random walks, with intersections allowed within each group and forbidden between different groups. We first study intersection exponents in two dimensions, where our results agree with the known exact formulas and test the numerical approach. In three dimensions, where no general exact expression is known, we determine $ \xi$ for a range of cases. For two groups containing $ k$ and $ m$ random walks, respectively, we obtain the exponents $ \xi(k,m)$ for $ k=1,2$ and $ m=1,2,\ldots,7$ . We further extend $ m$ to a continuous parameter $ \lambda$ , allowing us to obtain numerical values for $ \xi(k,\lambda)$ for $ k=1,2,3$ and $ 0.25\leq\lambda\leq3$ . Away from the smallest moment orders, these functions increase with $ \lambda$ with decreasing slopes, as expected from the strict concavity of Brownian intersection exponents. We also investigate three-group configurations for several representative cases. The resulting integer and continuous exponents supply numerical values for analytical studies of non-intersecting random paths.
Statistical Mechanics (cond-mat.stat-mech)
Interplay of Composition, Crystallinity, and Chemical Structure in CoHCF and NiHCF Thin Films Prepared at Different Temperatures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Larissa de O. Garcia, Michael Pohlitz, Mohammed F. Kalady, Christian K. Muller
Understanding how growth conditions govern structural order and ion transport in Prussian blue analogues (PBAs) thin films is essential for optimizing their electrochemical performance. Here, cobalt and nickel hexacyanoferrate (CoHCF and NiHCF) thin films were electrodeposited potentiostatically at temperatures between 20 and 60 degrees C. A combination of cyclic voltammetry, scanning electron microscopy, X-ray diffraction, and Raman spectroscopy was employed to elucidate the interplay between composition, crystallinity, and chemical structure. Under identical conditions, CoHCF exhibits a maximum current density approximately 2.2 times higher than NiHCF, indicating significantly faster electrochemical kinetics. X-ray diffraction reveals temperature-dependent lattice expansion without phase transitions, with a maximum near 40 degrees C, associated with structural relaxation and compositional variations. Raman spectroscopy further reveals temperature-dependent local structural evolution, where cyanide band narrowing at intermediate temperatures indicates improved short-range order, while band broadening at higher temperatures reflects increased defect density. These findings demonstrate that temperature-controlled defect redistribution governs both short- and long-range structural order in PBA thin films, directly influencing ion transport and electrochemical response. This work provides new insights into structure-property relationships in PBAs and establishes deposition temperature as a key parameter for tuning electrochemical functionality in hexacyanoferrate-based electrodes.
Materials Science (cond-mat.mtrl-sci)
Statistical mechanics of classical fractons on a line
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
Ylias Sadki, Abhishodh Prakash, S. L. Sondhi
We study the equilibrium statistical mechanics of one-dimensional classical Machian fractons: particles whose dynamics conserves a global dipole moment and whose Hamiltonian couples momentum differences through a position-dependent pair-inertia kernel. Compactly supported interaction kernels have a divergence in the Gibbs partition function, and have been shown to break ergodicity and symmetry by forming non-equilibrium steady states with particle clusters, evading the Hohenberg-Mermin-Wagner-Coleman theorem. In this paper, we consider kernels with non-compact support and study their ergodic properties. For exponentially decaying kernels, graph-Laplacian and matrix-tree bounds provide an extensive free energy suggesting that a putative statistical mechanical description is valid. Similarly, uniform non-local kernels have a super-extensive free energy and require a Kac rescaling. A generalized Hohenberg–Mermin–Wagner–Coleman argument, supported by finite-size scaling, implies symmetry-breaking density order parameter vanishes at all wave vectors melting the long-range translation-breaking density order of compact kernels. To study the resulting equilibrium ensemble, we construct a nonreversible event-chain Monte Carlo (ECMC) algorithm that samples the coupled position-momentum phase space while preserving the dipole moment and total momentum. The ECMC sampling is shown to quantitatively match long time-averaged quantites in Hamiltonian dynamics. The equilibrium liquid exhibits preferred short-range clustering and strongly non-Gaussian single-particle momentum tails associated with the correlated nature of positions and momenta. This paper provides a detailed investigation into the equilibrium liquid properties of the non-compact regime, whilst the companion paper investigates the mechanisms that relax the liquid.
Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el)
16 pages, 7 figures
C 1s core-level fingerprints of reconstructed titanium vacancies in titanium carbide
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Recent first-principles searches predict that a titanium vacancy in rocksalt TiC is not an empty octahedral site but can reconstruct through the formation of carbon Frenkel pairs and short C-C bonds. We determine the C 1s signatures of these local structures and assess whether they remain specific in the presence of disordered carbon. Site-resolved binding energies were calculated with a self-consistent core-hole method for an unreconstructed vacancy and four representative C-C-bonded reconstructions. The unreconstructed vacancy shifts its nearest-neighbour C 1s level by only -0.36 eV. In contrast, the largest positive shift in each reconstructed model ranges from 2.34 eV to 2.80 eV. The large shifts occur at carbon atoms participating in the reconstructed C-C network and correlate with markedly less negative Mulliken charges, providing candidate local fingerprints of vacancy reconstruction. However, an exploratory TiC/amorphous-C model shows that disordered carbon environments can extend into the same high-binding-energy range. Overall, the calculated shifts provide reference energies for experimental searches for reconstructed Ti vacancies in TiC.
Materials Science (cond-mat.mtrl-sci)
Electromagnetic Proximity Effects and Spontaneous Currents in Clean Superconducting Heterostructures
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-23 20:00 EDT
Jian-Lin Li, Chien-Te Wu, Klaus Halterman
When ferromagnets are brought into contact with a superconductor, superconducting proximity effects give rise to a variety of interesting phenomena, including oscillatory singlet Cooper-pair amplitudes and long-ranged odd-frequency triplet correlations induced by the exchange interactions in the ferromagnets. From an electrodynamic perspective, however, it is equally important to understand when and how spontaneous currents can emerge. To investigate the interplay between electromagnetic and conventional superconducting proximity effects, we study clean ferromagnet/ferromagnet/superconductor spin-valve heterostructures in which the relative angle between the two ferromagnetic layers can be tuned. Our approach is based on a self-consistent numerical solution of the coupled Bogoliubov-de Gennes and Maxwell equations, providing a microscopic description capable of resolving physics on atomic length scales. Several notable features emerge. In both the weak- and strong-exchange-field regimes, the central ferromagnetic layer plays a dominant role in generating sizable spontaneous currents when its exchange-field strength is varied. We further find that the resulting electromagnetic response extends across the entire superconducting layer, in sharp contrast to the short-ranged inverse proximity effect. In noncollinear configurations, the electromagnetic proximity effect also reconfigures the local magnetic-field orientation and reduces the angular mismatch between the fields in the two ferromagnetic layers. The long-ranged odd-frequency triplet amplitudes are consequently modified by the orbital response, which alters the underlying quasiparticle states by changing their momentum-space structure. Finally, our framework can be naturally generalized to other superconducting spintronic systems, possibly including Josephson junctions and altermagnet/superconductor heterostructures.
Superconductivity (cond-mat.supr-con)
Electrolyte Dependent Structure Transport Relationships in Electrodeposited Prussian Blue Analogue Thin Films
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Larissa de O. Garcia, Michael Pohlitz, Mohammed F. Kalady, Christian K. Muller
Understanding how electrolyte composition influences charge storage in Prussian blue analogues (PBAs) requires clarifying the coupled effects of structural disorder and ion transport. Here, we investigate Fe-, Co-, and Ni-based hexacyanoferrate thin films electrodeposited from KCl, NaCl, NH4Cl, and LiCl electrolytes under identical electrochemical conditions. Although all films retain the cubic PBA structure, electrolyte identity produces pronounced differences in lattice parameters, defect concentration, and local coordination environments. Na+ promotes lattice expansion accompanied by increased vacancy formation, microstrain, and structural heterogeneity, whereas K+ and NH4+ yield more structurally coherent frameworks. Raman spectroscopy shows that increasing structural disorder broadens the distribution of local coordination environments and correlates with increasingly dispersed electrochemical behavior. Electrochemical impedance spectroscopy further reveals coupled ion-electron transport, with impedance increasing by more than one order of magnitude from FeHCF to NiHCF. Notably, the CPE exponent decreases systematically with Raman band broadening, establishing a direct correlation between structural disorder and transport dispersion. These results demonstrate that electrolyte identity controls not only lattice dimensions but also the organization and connectivity of defect networks, highlighting structural coherence and accessible transport pathways as key factors governing electrochemical performance in PBA thin films.
Materials Science (cond-mat.mtrl-sci)
Intrinsic switching leads to oxygen diffusion and breakdown in hafnia ferroelectrics
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Xabier Diaz de Cerio, Iñigo Robredo-Magro, Jorge Íñiguez-González
Conventional ferroelectrics exhibit well-defined polarization states linked through electric switching. In fluorite-structured ferroelectrics like hafnia, though, switching and oxygen diffusion seem to coexist, enriching the nature of ferroelectricity. Here we address the intrinsic, room-temperature switching and diffusion kinetics of hafnia ferroelectrics using machine-learning molecular dynamics. We identify two distinct switching mechanisms that are both active at realistic time scales. Critically, our simulations reveal that, because the lattice does not dissipate fast enough the heat originating from localized switching events, these two processes concatenate in an avalanche-like manner leading to oxygen conduction. Our results thus show that intrinsic switching leads to breakdown in hafnia ferroelectrics. They also suggest how this outcome might be avoided through suitably designed field pulses.
Materials Science (cond-mat.mtrl-sci)
13+16 pages, 5+10 figures
Surface-bulk hybridization enhances the Berry curvature dipole in GaAs(110)
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Gastón Blatter, Jorge I. Facio, Jeroen van den Brink
Symmetry breaking at crystalline boundaries can enable electronic responses that are forbidden in the bulk. Here, we investigate the Berry curvature dipole (BCD) at GaAs(110) surfaces using first-principles calculations. While the BCD vanishes in bulk GaAs due to symmetry constraints, the reduced surface symmetry permits a finite dipole. We show that surface relaxation promotes hybridization between bulk and surface states, which strongly influences the surface BCD. Specifically, in unrelaxed slabs, the BCD arises predominantly from interband coupling among exponentially localized surface states lying within the projected bulk band gap. Surface relaxation shifts these states into the energy range of the bulk continuum, transforming them into surface resonances and promoting hybridization with bulk-like states. This hybridization generates pronounced Berry-curvature hot spots, resulting in an overall enhancement of the BCD. Our results highlight the importance of surface relaxation for accurately describing surface–bulk hybridization, which in turn plays a key role in Berry-curvature-driven responses at crystalline boundaries.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Detection of acoustic phonons in carbon by Raman spectroscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Konstantin Iakoubovskii, Andrey Katrusha, Weihua Peng, Jianguo Peng
We detected acoustic phonons in graphite and diamond by Raman spectroscopy supported by density functional theory calculations. The activation of these normally forbidden Raman modes was achieved via lattice amorphization in case of graphite and by boron doping in case of diamond. The doping-induced Raman signal in diamond was identified with substitutional boron of tetrahedral symmetry via its dependences on excitation wavelength and polarization. Comparison of the Raman spectra of amorphized graphite and heavily boron-doped diamond suggests the emergence of graphitic-like disorder in the diamond lattice. The reported approach is not limited to carbon and can be extended to a wide range of other materials.
Materials Science (cond-mat.mtrl-sci)
Bias-driven circular currents in a quantum ring: Effects of electron-electron and electron-phonon interactions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Moumita Mondal, Santanu K. Maiti
The phenomenon of bias-driven circular charge and spin currents in a ring nanojunction is investigated in the presence of electron-electron (e-e) and electron-phonon (e-ph) interactions within a tight-binding framework based on the non-equilibrium Green’s function formalism. The Lang-Firsov transformation is employed to map the interacting system onto an effective electronic model, which is subsequently treated within the Hartree-Fock mean-field scheme. By exploring the interplay among e-e interaction, e-ph coupling, and electrode-ring interface sensitivity, several intriguing features emerge in both circular charge and spin currents that, to the best of our knowledge, have not been reported previously. In addition to bias-driven circular currents, charge and spin-dependent junction currents through the nanojunction are also analyzed. Selective spin transport is achieved, leading to a high degree of spin polarization. All four current components, two associated with circular currents and two with transport currents, are systematically inspected over a wide range of parameter regimes to assess the sensitivity of the results to the relevant system parameters. Our findings provide useful insights into charge and spin transport phenomena in interacting nanojunctions with single- and multi-loop geometries.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
17 pages, 12 figures. Comments are welcome
Counterions between walls with surface charge modulations: Exact Poisson-Boltzmann solutions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
We study the thermal equilibrium of a classical system of identical point charges moving between two walls with parallel surfaces at a distance $ d$ , charged symmetrically with position-dependent surface charge densities. Specifically, we study the effect of surface charge modulation on the effective force (pressure) between the walls in the Poisson-Boltzmann limit. Based on Monte Carlo simulations at high temperatures, it is predicted that surface charge modulation reduces the pressure between the walls compared to uniformly charged wall surfaces with the same average surface charge density. We restrict ourselves to surface charge modulations in only one direction and, using a general solution of the two-dimensional Liouville equation, we construct exact solutions for the electrostatic potential. The surface charge density on the walls is generated inversely from this potential, which means that our exact results apply to a limited set of models with a specific variation of the surface charge density with distance $ d$ . Explicit analytical results show that surface charge modulation can both increase (small distances $ d$ ) and decrease (large $ d$ ) the pressure between the walls.
Statistical Mechanics (cond-mat.stat-mech)
26 pages, 7 figures
J. Stat. Phys. 193 (2026) 130
Effect of interaction range on the phase diagram of magnetic hedgehog lattices
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Midori Yamada, Kotaro Shimizu, Shun Okumura, Yasuyuki Kato, Yukitoshi Motome
Topological spin textures have attracted considerable attention through their emergent electromagnetic properties, including the topological Hall effect and the topological Nernst effect. Among them, magnetic hedgehog lattices (HLs) are three-dimensional topological spin textures that host emergent magnetic monopoles and antimonopoles. HLs have been identified in metallic compounds, such as $ \mathrm{MnSi}_{1-x}\mathrm{Ge}_x$ and $ \mathrm{SrFeO_3}$ . Various theoretical models have been proposed, with either short-range or long-range interactions, which are typically regarded as effective descriptions of insulating and metallic systems, respectively. However, the role of the interaction range in stabilizing the HLs remains only partially understood. To address this gap, we investigate the stability of HLs by systematically varying the range and spatial decay of the exchange interactions, thereby interpolating between interaction profiles commonly associated with localized-spin insulating models and itinerant-electron metallic models. Based on extensive Monte Carlo simulations, we find that HLs are stabilized over a broad interaction range. Intriguingly, among the interaction profiles examined, intermediate-range interactions are particularly favorable for stabilizing HLs. They give rise to two distinct types of $ 3Q$ -HLs that differ in the number of monopole-antimonopole pairs per magnetic unit cell, and their relative stability depends sensitively on the interaction range. Our results provide a unified framework for tuning phase diagrams from microscopic interaction models, serving as a guideline for interpreting experiments in candidate materials.
Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 9 figures
Observation of the Nernst effect driven by longitudinal spin fluctuations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Fuyuki Ando, Hiroto Adachi, Hossein Sepehri-Amin, Takamasa Hirai, Keisuke Hirata, Ken-ichi Uchida
The Nernst effect, which converts a heat current into a charge current in the orthogonal direction, is generally classified into the ordinary effect due to an external magnetic field applied to conductors and the anomalous effect due to static magnetization in magnetic materials. Thus, one expects that the anomalous Nernst effect disappears at the Curie temperature following the magnetization. Here, we observe the Nernst effect which rather manifests around the Curie temperature. In a series of ferromagnetic (Mn,Cr)Sb samples, the Nernst coefficients exhibit finite values even across the Curie temperatures, whereas the anomalous Hall resistivity disappears, suggesting the breakdown of the Mott relation. These surviving Nernst and vanishing Hall effects result in a peak behavior of the transverse thermoelectric conductivity around the Curie temperature, which we theoretically reproduce by introducing longitudinal fluctuations of spins without accounting for an exotic spin texture, a non-trivial electronic structure, or magnon- and phonon-drag effects. The Nernst effect driven by the longitudinal spin fluctuations reveals that not only the static magnetic order but also the spin fluctuations can be a driving force of the Nernst effect in magnetic materials, opening another way for boosting transverse thermoelectric conversion.
Materials Science (cond-mat.mtrl-sci)
Linear and nonlinear active microrheology of viscous, viscoelastic, and elastic media: A fluid particle dynamics approach
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Muhammed Muhsin Abdul Azeez, Henning Reinken, Andreas M. Menzel
Active microrheology is an effective tool to determine the rheological properties of viscous, viscoelastic, or elastic materials on microscopic length scales. The positional response of an embedded probe particle to an externally applied oscillating driving force allows to indirectly characterize the properties of the surrounding media. We aim to explore the linear and nonlinear response of probe particles in a microrheological setup of planar geometry. For this purpose, we extend the computational method of fluid particle dynamics from viscous fluid-like to viscoelastic and elastic media, including nonlinear regimes. We consider a system confined by solid walls. In this case, we validate the approach by quantifying the linear response in terms of a Jeffreys model. Increasing the amplitude of the driving force, we observe distinct nonlinear effects. They include distorted stress-strain curves and a gradual net drift of probe particles initially positioned close to a wall. This drift vanishes in the viscous fluid-like and elastic solid-like limits, but is manifest for intermediate viscoelastic systems. We further address a setup of two probe particles in the absence of walls. They experience reciprocal pairwise oscillatory forcing. Here, nonlinearities in viscoelastic systems induce a net drift gradually moving the particles further apart from each other. Comparing with real setups, our implementation of the driving force is in line with experimental setups of optical tweezers or active magnetic microrheology.
Soft Condensed Matter (cond-mat.soft)
Reinterpreting ultrafast experiments on supercooled water: Glass transition versus liquid-liquid criticality
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Water’s anomalous properties have been hypothesized to originate from a liquid-liquid critical point in the supercooled regime, separating high- and low-density liquid states. Experimental verification remains challenging due to rapid crystallization under these conditions. A recent study reported evidence for such a transition, based primarily on a pronounced increase in the heat capacity of rapidly heated low-density amorphous ice. Here, we show that this heat capacity increase can be explained without invoking a liquid-liquid transition. By combining simulations using a machine-learning potential trained on the state-of-the-art MB-pol water model, combined with the Tool-Narayanaswamy-Moynihan (TNM) model of the glass transition, we demonstrate that the observed signal can arise instead from a dynamical effect induced by the mobilization of rotational and translational molecular degrees of freedom during ultrafast heating. We further show that our findings are fully consistent with recent electron diffraction measurements showing structural arrest of supercooled water close to our predicted glass-transition temperature. These results provide an alternative interpretation of the experimental observations and highlight the importance of nonequilibrium glassy dynamics in the interpretation of the behavior of supercooled water on ultra-short time scales.
Soft Condensed Matter (cond-mat.soft)
Extraordinary Lifetime Enhancement of Coherent Phonon-Amplitude Modes in the Excitonic Insulator Phase of Ta2Pd3Te5
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Anjan Kumar N M, Shuhan Wang, Snehashish Chatterjee, Yan Zhu, MinJae Kim, Tobias Ritschel, Elaheh Sadrollahi, Jochen Geck, Achim Rosch, Chandra Shekhar, Claudia Felser, Stefan Kaiser
The excitonic insulator (EI) is an electronic phase of condensed excitons. However, in many prototypical materials the presence of a concurrent structural transition complicates the identification of a purely electronic origin of the ordered state. Here, we investigate Ta2Pd3Te5, in which an EI phase develops below TC ~ 100 K in the absence of a detectable structural transition. We characterize the excitonic condensate via its coherent phonon-amplitude response. Most strikingly, an extraordinarily strong lifetime enhancement of these modes sets in below TC which we establish as a new and robust fingerprint linked to exciton condensation. We discuss possibilities to capture the enhancement when taking into account a coupling of excitonic and lattice effects in line with the coupled phonon-amplitude response. Within an order-parameter polaron picture coupling to the excitonic state may dress the phonon mode and thereby suppress its relaxation and a phenomenological model combines the anharmonic phonon response and a reduced electronic scattering due to the gap opening in the EI phase.
Strongly Correlated Electrons (cond-mat.str-el)
11-page manuscript with 3 figures; 19 pages of Supplemental Material with 16 figures
Deep Generative Crystal Structure Prediction: A Benchmark Study and a Controlled Test of Prototype Dependence
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Lai Wei, Rongzhi Dong, Ying Feng, Madeline Miklos, Jianjun Hu
Deep generative models are widely reported to enable de novo crystal structure prediction (CSP), but their capability has not been measured consistently against template-based methods. We evaluate 12 representative generative CSP models, spanning latent-variable, diffusion, flow-matching, autoregressive, and manifold random-walk architectures, against TCSP 2.0 on 180 test structures and a leakage-controlled subset of 46. All methods use identical structure-matching, symmetry, and consensus criteria. Template retrieval is the strongest single method, reaching 68.3% top-1 success; symmetry-aware EquiCSP (66.4%) and Uni-3DAR (62.9%) form the next tier. However, comparison with TCSP 2.0 shows that most structures correctly predicted by generative models are also correctly predicted by template substitution. Thus, the set of structures uniquely reachable by generation is small, limiting its practical advantage for discovering structures outside existing prototype libraries. To test the source of this performance, we removed entire stoichiometric prototype families from the training set and retrained the strongest generative model. Accuracy declined by 50-78% across four families, establishing that performance is substantially prototype-dependent. A small minority of structures survived removal of their prototype family, demonstrating a real but limited retrieval-independent predictive capacity. Present generative CSP models therefore function largely as implicit, softer-edged prototype libraries rather than genuinely de novo predictors. Enlarging this residual capacity, rather than aggregate match rate alone, is the central open problem.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
18 pages
Neural Network Backflow with Low-Rank Multi-Determinant Updates
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Tianshu Huang, Xiaowei Ou, Vidvuds Ozolins
Simulating strongly correlated fermions remains a long-standing challenge due to the exponential complexity of the Hilbert space and the intricate sign structure of many-body wavefunctions. We introduce a variational framework centered on a neural network backflow transformation that combines deep learning with variational Monte Carlo. The proposed ansatz employs a multi-determinant expansion with low-rank shifts to capture non-local correlations and complex sign structures. Applied to the two-dimensional Hubbard model at both half-filling and $ 1/8$ doping, the method achieves energies within $ 0.45%$ of auxiliary-field quantum Monte Carlo at half-filling and captures intertwined charge- and spin-density stripe patterns at $ 1/8$ doping. These results demonstrate the potential of this framework as a scalable and interpretable approach to variational simulations of strongly correlated fermionic systems.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
16 pages, 13 figures
Topology-Stratified Materials Discovery with A Flow-Based Generative Model
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Jingyi Zhou, Oyshee Chowdhury, Noah Oyeniran, Chongze Hu
Accurate generation of crystal structures is the foundation to the discovery of high-performance materials for extreme-environment applications, such as aerospace, additive manufacturing, and fusion energy systems. Although generative modeling has emerged as a promising approach for crystal design, its performance remains limited by the complex crystal structures and diverse chemical compositions. In this work, we develop UFO-MGen, a universal flow-based generative model that learns topological features of Wyckoff representations and leverages this information to accurately generate crystals across vast structural and chemical spaces. Compared with state-of-the-art generative models, UFO-MGen achieves the highest crystal generation success rate under a rigorous multi-stability evaluation framework, the highest SUN (stable, unique, novel) rate, and a remarkable extrapolation capability that has not been reported by previous models. Furthermore, a fine-tuning module is implemented to UFO-MGen for property-constrained crystal generation, enabling the inverse materials design toward target properties. The UFO-MGen opens a new avenue for accelerated materials discovery and providing a foundation for universal materials intelligence.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI)
Superfluorescence as a cooperative amplifier of hidden anisotropy in a ferroelectric hybrid perovskite
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Changhao Gao, Daniel Sandner, Talia Ruhrberg Estévez, Jeron Timmer, Sophia Klubertz, Martijn Kemerink, Felix Deschler
Superfluorescence (SF), intense picosecond bursts from self-synchronizing dipoles, is promising for room-temperature quantum sources. Yet, whether this synchronization can convert weak structural anisotropies into robust macroscopic order remains an open question. Here, we demonstrate that polycrystalline ferroelectric 2D perovskite thin films exhibit strongly linearly polarized SF with a degree of polarization (DOP) up to 86%. Remarkably, macroscopic polarization emerges without external bias despite randomly oriented microscopic domains, suggesting a cooperative gain mechanism that amplifies weak local anisotropies by several orders of magnitude into coherent, linearly polarized light bursts. Our results establish cooperative superfluorescence as a general concept for translating microscopic anisotropy into robust macroscopic order, exemplified here for linear polarization, offering a sensitive probe of hidden material symmetries and a framework for polarized quantum light sources
Materials Science (cond-mat.mtrl-sci), Optics (physics.optics)
Microstructure, tensile behavior and cyclic bendability of directly extruded biodegradable Zn, Zn-Mg and Zn-Mg-Sr wires
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
L. Hlodák, K. Tesař, M. Lebeda, J. Duchoň, J. Kubásek, J. Čech, A. Školáková, J. Pinc
Zinc-based alloys are promising biodegradable implants, yet the trade-off between strength, ductility, and bendability in thin-wire form remains poorly understood. To address this, pure Zn (PZ), Zn-0.15Mg (ZM), and Zn-0.8Mg-0.2Sr (ZMS) wires of ~290 um diameter were produced by direct extrusion, and their microstructure, texture, tensile, and bending behavior were characterized. Mg2Zn11 and SrZn13 phases promoted particle-stimulated nucleation, refining the grain size from 35.8 um in PZ to 6.8 and 3.3 um in ZM and ZMS, respectively, weakening the basal-fiber texture, and raising the ultimate tensile strength at 37 °C from about 119 MPa for PZ to 291 and 334 MPa for ZM and ZMS, respectively. PZ deformed through twin transmission across weakly misoriented grains, producing serrated stress drops in tensile curves, with further straining accommodated by non-basal slip. ZM showed a single, aging-sensitive stress drop from localized twin nucleation and particle cracking, while ZMS showed distributed particle cracking without associated stress drops, consistent with its higher elongation to failure of 19 % at 37 °C. Mechanical properties remained broadly stable after 20 days of aging at 37 °C, with no measurable change in the nanoscale precipitates after 7 days. All compositions, however, showed markedly poor cyclic bendability accompanied by a twinning-detwinning mechanism directly observed by EBSD for the first time in zinc. These results establish single-step direct extrusion as a viable route to strong, fine-grained biodegradable Zn wires, while identifying poor bendability as the principal obstacle to bending-critical biomedical devices.
Materials Science (cond-mat.mtrl-sci)
Topological phase transition driven by structural defects
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-09-23 20:00 EDT
Andrii Syrota, Andrej Mesaros, Pascal Simon
Structural defects, such as disclinations and dislocations, destroy the long-range crystalline order as they proliferate. In this work, we continuously drive a system from a crystalline state on a decorated honeycomb lattice to a hyperuniform amorphous state, by consecutively introducing Stone-Wales (SW) defects, which can be viewed as dipoles of dislocations. Using a topological Weaire-Thorpe Hamiltonian model to describe electrons in this system, we demonstrate that SW defects can cause pseudo-band inversions and, correspondingly, a reversal of the Chern number. Using adiabatic arguments and a computationally efficient spillage indicator, we predict the topological phase diagram of the amorphous state from the crystalline one. We explain the nature of the pseudo-band inversion through the renormalization of the hopping in an effective Hamiltonian based on a single SW defect.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
19 pages, 12 figures
Crystal Electric Field Analysis on the Magnetic Properties of Ferromagnetic CeRu$_2$Ge$_2$ Single Crystal
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Shovan Dan, Suman Nandi, Gourav Dwari, Bishal Baran Maity, Bhagyashree A Chalke, Ruta Kulkarni, P. D. Babu, Arumugam Thamizhavel
We report a detailed anisotropic studies on the magnetic and transport properties of a CeRu$ _2$ Ge$ 2$ single crystal. A clear ferromagnetic transition is observed at $ T{\rm C} = 7.5$ K in the magnetic susceptibility, electrical resistivity and heat capacity measurements. The magnetoresistance (MR) is positive at low temperature within the magnetically ordered state. We confirmed the presence of a magnon excitation gap in the resistivity, MR and the low temperature heat capacity data. The pronounced anisotropy observed in the magnetic susceptibility and magnetization along the [100] and [001] directions is quantitatively explained within the crystal electric field (CEF) framework using the point-charge model. The analysis reveals a CEF level scheme comprising three doublets, with a ground state and two excited states at 491 and 671K, that was further confirmed from the Schottky effect in the magnetic part of the heat capacity data. Unlike most Kondo lattice ferromagnets of Ce compounds, where the magnetic easy axis deviates from the expected CEF ground state, CeRu$ _2$ Ge$ _2$ exhibits magnetization, which is fully consistent with the CEF derived ground state wave function, with the easy axis of magnetization aligned along the [001] direction.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
5 figures,10 pages
Unraveling the Emergence of Slow Dynamics in U(1) Lattice Gauge Theories
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
Riccardo Andreoni, Zala Lenarčič, Zeno Bacciconi, Antonello Scardicchio, Marcello Dalmonte, Devendra Singh Bhakuni
The dynamics of gauge theories is of fundamental interest, with low-dimensional systems displaying a rich phenomenology beyond the rapid thermalization typical of QCD and non-Abelian theories. In particular, recent quantum simulation experiments have reported robust and unexpected signatures of slow relaxation in generic regimes and at large volumes in one-dimensional U(1) lattice gauge theories (LGTs), whose origin remains poorly understood. Here, we present a framework that provides a unified perspective on such slow dynamics and establishes a new route for exploring subdiffusive fractonic hydrodynamics in Rydberg experiments. The backbone of our theory is an exact analytical mapping from U(1) LGTs with a topological $ \theta$ angle to non-local kinetically constrained fermionic models with an emergent linear Stark potential. In the absence of the $ \theta$ term, this framework interprets the non-thermal dynamics reported in recent experiments as prethermal behavior arising from proximity to an integrable free-fermion model. For non-zero $ \theta$ , the emergent Stark potential instead explains the freezing dynamics observed in other recent experiments. We argue that this correspondence could also lead to subdiffusive transport due to emergent conservation laws. We predict that these phenomena arise in a much broader class of models, and support this prediction with numerical simulations and proposals for future experiments.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Lattice (hep-lat)
17 pages, 8 figures
Adsorption of the low density lipoproteins on the micropatterned polymer brush: computer simulations
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
J. Ilnytskyi, D. Yaremchuk, O. Komarytsia
Photorenewable polymer adsorbents, aimed at reducing the low density lipoproteins (LDLs) level, are reported experimentally. Previously we developed a mesoscale model for this setup with uniformly grafted chains, and examined the role played by chains length and grafting density [Ilnytskyi, et al., Processes, 2023, 11, 2913]. The analysis is extended here to the cases of bunch-like and grid-like grafting micropatterns. The bunch-like arrangement is the most efficient one displaying low- and high-density peaks for adsorbing effectiveness. The former peak is twice higher compared with uniform grafting, as a consequence of a match between LDLs dimensions and the micropattern pitch. Adsorption isotherms are fitted well by either Langmuir or logistic growth forms, indicating a higher growth rate compared with uniform grafting. The high-density peak exists only for this micropattern and extends the applicability of an adsorbent. At the highest LDL concentration, adsorption is hampered by self-assembly of LDLs into a packed cubic phase.
Soft Condensed Matter (cond-mat.soft)
18 pages, 10 figures
Dense Packing of Tetrahedra in Cylinders
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Gabrielle N. Jones, Adil Mughal, Philipp W.A. Schönhöfer, Sharon C. Glotzer
We present the first systematic investigation of regular tetrahedra densely packed within a circular cylinder. Combining numerical simulations with exact analytical theory, we classify the densest configurations into two continuous, mathematically tractable families: chiral Tetra Helices and achiral Dimer Chains. Crucially, we reveal that the celebrated Boerdijk-Coxeter Helix is not an isolated anomaly, but a natural consequence of this cylindrical confinement. We further identify a striking symmetry-breaking bifurcation at a critical diameter, where the chiral helix coexists with an achiral dimer chain at a strictly identical packing fraction.
Soft Condensed Matter (cond-mat.soft)
12 pages, 1 Table, 6 Figures
The observation of bulk superconductivity in Rhombohedral ReO3 under pressure
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-23 20:00 EDT
S. Huyan, R. F. S. Penacchio, L-L. Wang, J. Schmidt, D. Zhang, B. Lavina, Z. Li, R. A. Ribeiro, T. J. Slade, J. Zhao, S. L. Morelhão, P. C. Canfield, S. L. Bud’ko
Understanding how lattice geometry enables superconductivity in oxides remains a central challenge. Here, we report a systematic study of ReO3 up to 80 GPa. Synchrotron X-ray diffraction, Raman spectroscopy, electrical transport, dc magnetic susceptibility, and first-principles calculations establish a sequence of pressure-induced structural transitions, from cubic Pm-3m to Im-3 followed by the emergence of a rhombohedral R-3c phase accompanied by bulk superconductivity with a maximum Tc, onset ~17.5 K. DC magnetic susceptibility and trapped-flux magnetization measurements demonstrate that bulk superconductivity is confined to the pressure range where R-3c phase is dominant. Density functional theory calculations show strong electron-phonon coupling in the hR24-R-3c structure, with substantial contributions from both low-frequency Re vibrations and high-frequency oxygen-related phonon modes, yielding a calculated Tc comparable with the experiment. Upon further compression above ~35-40 GPa, powder X-ray diffraction results indicate a symmetry-lowering structural transition. Whereas the experimental diffraction patterns can be best described by a rhombohedral-derived R32-like average distortion with effective enlargement of the crystallographic unit cell, enthalpy calculations identify a lower-symmetry mP16-P2/c structure driven by phonon instability of the R-3c phase. This reconstructed higher-coordination phase has a reduced density of states at the Fermi level, weaker electron-phonon coupling, and a much lower calculated Tc, providing a microscopic explanation for the loss of bulk superconductivity in the higher-pressure phase. These results show that bulk superconductivity is stabilized within the rhombohedral structure, where pressure-induced lattice reconstruction supports enhanced electron-phonon coupling through cooperative Re-O lattice dynamics.
Superconductivity (cond-mat.supr-con)
29 pages, 8 figures
S. Huyan, R.F.S. Penacchio, L.-L. Wang et al., Materials Today Physics, 67, 102206 (2026)
Berry-Landau Fermi-liquid theory: transport in presence of quantum geometry
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Shuai A. Chen, Roderich Moessner
Landau Fermi-liquid theory characterizes interacting metals through quasiparticles and their residual interactions. It is a challenge to incorporate non-trivial quantum geometry – as encoded by Berry phases and the quantum metric – as a fundamental ingredient. We formulate a Berry-Landau Fermi-liquid theory for spinless fermions within an isolated band crossing the Fermi surface and derive the Landau functional through the Nozières–Luttinger construction. The instantaneous response to a perturbation of the Bloch waves generates both an anomalous Berry-connection potential in the action and an interaction-induced quantum-geometric contribution to the quasiparticle current. The conserved physical charge current is then obtained via the electromagnetic Ward identity as a combinati of this quantum-geometric current and the bare drift current. Therefore, the intrinsic anomalous Hall conductivity is fixed by the Berry-curvature integral of the dressed quasiparticle band while the Drude weight contains both conventional and quantum-geometric contributions. In the presence of Galilean symmetry, the Drude weight is protected against interaction renormalization. In the flat/narrow-band limit, transport is dominantly quantum-geometric and can be thermally enhanced. These results establish quasiparticle occupations, Landau interactions, and the quantum geometry carried by quasiparticles as the fundamental low-energy ingredients of a Berry-Landau Fermi liquid.
Strongly Correlated Electrons (cond-mat.str-el)
21 pages. Comments are welcome
Tilt-controlled Drude anisotropy in nodal-line semimetals: logarithmic enhancement, interband correction, gauge consistency, and the Landau-damping window
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
We study the anisotropic charge response of a three-dimensional tilted nodal-line semimetal in which the tilt enters the spectrum through an identity term and acts as the model control parameter. Using the Kubo formula with line-integral vertices, we show that the tilt-induced deformation of the low-energy phase space produces parametrically different longitudinal and transverse Drude responses: the longitudinal weight grows logarithmically as $ D_{zz}=B\ln(1/\delta)$ with the analytically determined coefficient $ B=g/(2\pi)^2$ —within the window in which the Fermi-surface tail lies inside the ultraviolet cutoff, while at a fixed physical cutoff the weight saturates instead at a cutoff-set plateau—whereas the transverse weight follows a stronger algebraic scaling $ D_\perp\sim\delta^{-1}$ ; the leading $ \sqrt\delta$ corrections to both asymptotic forms are obtained analytically. The interband polarization retains the $ q^2$ long-wavelength structure, with a coefficient that is infrared-integrable through Pauli blocking at finite doping yet carries a slow ultraviolet logarithm; it renormalizes the collective mode multiplicatively and sets the interband absorption threshold $ \omega_c=2\mu/(1+|\eta_z|)$ . A self-consistent solution of the plasmon dispersion identifies a tilt-dependent damping-free window bounded by the interband continuum. We predict that the type-II extension of this window, within the stated bandwidth (Brillouin-zone-like) cutoff regularization, contains a candidate low-frequency acoustic-like branch outside the particle–hole continua for $ \eta_z\gtrsim1.2$ over a finite window in momentum transfer.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Agent-E2MD: Autonomous Translation of Interatomic Potential Equations into Physically Validated Pair Styles for Molecular Dynamics in LAMMPS
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Bilvin Varughese, Orcun Yildiz, Aditya Koneru, Henry Chan, Tom Peterka, Subramanian Sankaranarayanan
Interatomic potentials underpin MD and govern predictive atomistic-model fidelity for metals, semiconductors, oxides, liquids, and reactive systems. A potential has limited practical value until reliably implemented in production MD code. Slow, expertise-intensive implementation requires more than equation-to-C++ translation: it must select the neighbor-list architecture, evaluate and distribute many-body derivatives, manage interprocessor communication, and preserve host-code energy, force, and virial conventions. We introduce Agent-E2MD, a knowledge-guided agentic workflow that translates user-specified interatomic models into executable LAMMPS pair styles. It combines architectural classification, code generation, autonomous build-test-fix cycles, simulation execution, and hierarchical physical validation. We test Agent-E2MD on seven material-potential pairs: Lennard–Jones Ar, EAM/FS Ag, MEAM Bi, Tersoff Si, GAP Ni, ReaxFF C/H/N/O, and a recently developed Symbolic Regression EAM (Symb EAM) model for Al, currently unavailable in LAMMPS. Single-point results match reference energies and forces for all seven models. Five crystalline many-body benchmarks recover reference relaxed lattice properties, vacancy formation energies, and elastic constants. Ag, Bi, Si, and Ni are stable at finite temperature in nanosecond-scale simulations; ReaxFF extends validation to reactive dynamics with evolving bond order and charge equilibration. Results demonstrate that the software architecture for an interatomic potential can be inferred from its physical and mathematical structure. Agent-E2MD does not replace scientific judgment; it shifts users’ effort from routine implementation to model definition, rigorous validation, and physical interpretation. The framework provides a practical, traceable bridge between emerging AI-driven potential discovery methods and production-scale atomistic simulations.
Materials Science (cond-mat.mtrl-sci)
Autonomous Quantum Transport Measurements of 2D Semiconductors by an AI Agent
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Brandon Bauer, Matthew Whalen, Kenji Watanabe, Takashi Taniguchi, John Q. Xiao, Tao E. Li, Wenjin Zhao
Artificial-intelligence (AI) agents are beginning to enter experimental laboratories, automating experiments and accelerating scientific discovery. Herein, we introduce an AI-driven workflow in which an AI agent performs multi-step, multi-day quantum transport measurements end-to-end. Specifically, given brief instructions, the agent starts by planning the multi-step measurements, then safely operates the cryogenic instruments, analyzes the data, and concludes with a final report. We demonstrate this AI workflow on multiple monolayer and bilayer MoS2 devices. Through autonomous measurement campaigns lasting up to six days, the agent determined the conduction-band spin-orbit coupling energy in monolayer MoS2, and mapped a layer- and valley-resolved phase diagram in bilayer MoS2. This experimental workflow is implemented through the FermiLink agent harness, which emphasizes instrumental safety and the reliability of the measurement and analysis. The framework is general and can be readily adapted to other types of experiments, representing a step toward self-driving laboratories.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Direction-dependent magnetoelectric conductivity from dipolar topological semimetals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
We compute the linear magnetoelectric conductivity of a two-band vortex nodal-ring (VNR) semimetal and a three-band Hopf semimetal (HSM) within the semiclassical Boltzmann formalism in the relaxation-time approximation. We consider three inequivalent planar-Hall configurations, in which the electric ($ \boldsymbol E$ ) and magnetic ($ \boldsymbol B$ ) fields are oriented differently with respect to the nodal-ring plane and the BC-dipole axis. Unlike Weyl and multifold semimetals, where Berry-curvature (BC) flux originates from monopole-like sources, both systems host dipole-like BC sources and vanishing Chern numbers. Working consistently to cubic order in the magnetic field, we evaluate the Drude, BC, orbital-magnetic-moment (OMM), anomalous-Hall, and Lorentz-force contributions to the conductivity. In both systems, the dipolar BC and OMM generate odd powers of $ |\boldsymbol B|$ in in-plane response channels that are symmetry-forbidden in systems with monopole-like BC sources. For the HSM, the internode-scattering contribution to the conductivity vanishes identically. By comparing the VNR with a $ \mathcal{PT}$ -broken gapped nodal ring and the HSM with a pseudospin-1 triple-point semimetal, we demonstrate that the dipolar nature of the BC gives rise to distinctive features in magnetoelectric response that are absent in semimetals with monopole-like BC flux.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), High Energy Physics - Theory (hep-th)
55 pages, 9 figures
Mesoscale heterogeneity in protein hydrogels induced by dynamic unfolding and post-gelation rearrangements
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Victoria Byelova, Lorna Dougan, David Head
The rationalization of protein hydrogel design is essential in creating bespoke and functional materials for a range of medical and healthcare applications, such as tissue engineering, wound healing and bio-sensors. The dynamic process of protein unfolding can significantly influence the resultant gel structure and behaviour - conformational changes in individual protein building blocks affect the bulk gel, whilst changes to bulk conditions influence how individual proteins move and respond. In order to characterize and control protein hydrogels, a multi-lengthscale picture must be built so that this complex interplay can be understood. We develop a coarse-grained computational model to investigate fundamental aspects of dynamic unfolding within chemically crosslinked protein hydrogels, focussing on the mesoscale structure during and after gelation. In simplifying protein unfolding to a single dynamic step, we are able to create a heterogeneous network formed of coarse-grained proteins. We observe evolving hydrogels consisting of regions of high-density protein clusters with a low degree of unfolding due to local crowding effects, interconnected by low-density stranded regions with a higher concentration of unfolded proteins. Systematically varying the barrier height for single protein unfolding demonstrates a weak influence on the mesoscale structure as characterised by fractal dimension and correlation length. Conversely, the measured changes in these parameters are greater after the gel experiences sustained conformational relaxation. This work demonstrates the effectiveness of coarse-grained modelling in capturing the heterogeneous mesoscale network of crosslinked unfoldable proteins. A greater predictive understanding of the structure and behaviour of protein hydrogels is gained through this model and will accelerate the design of novel biomaterials.
Soft Condensed Matter (cond-mat.soft)
9 pages, 8 figures
Disentangling Surface Charge and Electrolyte Effects on Interfacial Water at Electrified Pt(111)
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Thorben Eggert, Lang Li, Yair Litman, Karsten Reuter, Nicolas G.Hoermann, Clotilde S. Cucinotta
The structure of interfacial water at electrified metal electrodes is known to affect electrocatalysis, and experiments highlight its sensitivity to electrolyte ion identity and applied bias. To disentangle generic charge-controlled structural changes from ion-specific effects, we compare ab initio molecular dynamics water structures at electrified Pt(111) generated with two very different biasing schemes: an explicit ion imbalance in the double layer and homogeneously distributed partially charged hydrogen atoms. Despite these distinct counter-charge representations, both approaches yield a consistent average response of the first water bilayer, in particular of the chemisorbed first layer, when compared on a common surface-charge scale. Method-dependent differences, in particular those associated with explicit electrolyte ions, become apparent only in more local structural descriptors. The hydrogen-bond topology reveals charge-dependent chain-to-ring rearrangements, with explicit ions enhancing ring populations near the potential of zero charge. Layer-resolved vibrational density of states (VDOS) assigns the strongest O-H stretching perturbation to chemisorbed first-layer water and identifies high-frequency signatures of ion-coordinated water, while computed vibrational sum-frequency generation (VSFG) spectra show that the physisorbed, electrolyte-facing region is particularly sensitive to the counter-charge representation. These results suggest that surface charge controls the average structural response, whereas electrolyte ions and their solvation shells become visible only when locally refined descriptors are investigated or probed, e.g. the H-bond network topology and vibrational fingerprints of the interfacial bilayer.
Materials Science (cond-mat.mtrl-sci)
32 pages, 5 figures, 1 table. Supporting Information (14 pages, 14 figures, 1 table) appended
Benchmarking the generalized Kadanoff-Baym ansatz and second-order adiabatic expansion using time-dependent spintronic effects: Spin pumping, torque, and inertia
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Jalil Varela-Manjarres, Nicole Sofia Salazar-Delgado, Branislav K. Nikolic
The generalized Kadanoff-Baym ansatz (GKBA) [P. Lipavský {\em et al.}, Phys. Rev. B {\bf 34}, 6933 (1986)] has emerged as a popular and numerically efficient algorithm for simplification of nonequilibrium Green’s function (NEGF)-based calculations of time-dependent quantum transport. For systems that can be split into classical and quantum degrees of freedom, another popular simplifying strategy is adiabatic expansion (AE) of NEGF [N. Bode {\em et al.}, Phys. Rev. Lett. {\bf 107}, 036804 (2011); S. Deghi {\em et al.}, Phys. Rev. B {\bf 110}, 115409 (2024)] in terms of the velocity of classical degrees of freedom, such as localized magnetic moments (LMMs) in spintronics or coordinates of nuclei in nanoelectronics. Here we compare GKBA and second-order AE with numerically exact benchmarks for two-terminal junctions whose central region hosting quantum electrons and classical LMMs is attached to two semi-infinite normal metal leads. Three simple models are employed to exhibit cornerstone time-dependent effects in spintronics—spin pumping and spin-transfer torque (STT), as well as magnetic inertia as a recently explored phenomenon. We find that GKBA fails to describe pumping of spin current by precessing LMMs, or STT vectors, and thereby induced LMM dynamics. Conversely, the second-order AE matches numerically exact benchmarks for both effects remarkably well, thereby also revealing the essentially {\em nonadiabatic} nature of spin pumping. Thus, AE opens a path toward an accurate description of STT-driven magnetization dynamics, including combination with first-principles Hamiltonians, while incurring a fraction of the cost of time evolution of full NEGF. However, despite including terms up to the second time derivatives of LMMs into AE, this approach fails to capture fast nutational oscillations on top of the precessional motion of LMMs as the hallmark of magnetic inertia.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
13 pages, 6 figures, 106 references
Real-Frequency Diagrammatics with Pole Representations
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-23 20:00 EDT
Rayan Farid, Lei Zhang, Aiman Al-Eryani, Agnieszka Jażdżewska, Emanuel Gull
Finite-temperature many-body theories are typically formulated in imaginary time, where they are amenable to efficient numerical treatment. However, the extraction of spectral properties from the imaginary axis is difficult and requires numerical analytic continuation, while a direct formulation on the real axis requires prohibitively expensive numerical quadrature. In this paper, we represent the objects of many-body perturbation theory using systematically improvable pole and moment expansions and develop the corresponding framework for evaluating diagrammatic contributions directly on the real axis. We introduce a controlled recompression procedure that prevents the proliferation of poles under algebraic and diagrammatic operations. We benchmark the approach on paradigmatic quantum impurity problems and apply it to self-consistent calculations of the uniform electron gas. The resulting spectral quantities converge systematically towards numerical accuracy. This work provides a practical framework for controlled and systematically improvable calculations of spectral quantities within diagrammatic many-body theories, including self-consistent conserving approaches.
Strongly Correlated Electrons (cond-mat.str-el), Mathematical Physics (math-ph)
20 pages, 15 figures
Nonlinear Spin Polarization Enables Néel Order Switching in Centrosymmetric Altermagnets
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
Sunit Das, Sayan Sarkar, Amit Agarwal
Deterministic electrical switching of the Néel order remains challenging in centrosymmetric altermagnets, where linear current-induced spin polarization is forbidden by inversion symmetry. Here, we establish a nonlinear route to Néel order control. Spin group symmetry shows that, in the nonrelativistic limit, the nonlinear spin polarization is constrained along the Néel vector, with a staggered response allowed in $ 8$ of the $ 10$ nontrivial spin-Laue groups. Although this Néel spin polarization is torque-inactive by itself, finite spin-orbit coupling can generate an additional uniform component transverse to the Néel vector. Using a minimal model for the $ d$ -wave altermagnet FeSb$ _2$ , we demonstrate the coexistence of the nonrelativistic staggered response with an SOC-induced uniform transverse component. Landau-Lifshitz-Gilbert equation-based macro-spin simulations reveal that the transverse component alone produces oscillatory dynamics, whereas its cooperative action with the staggered response enables deterministic $ 180^\circ$ reversal. We further show that changing the electric field orientation reverses the staggered spin response and selects the switching direction, while the opposite Néel states can be distinguished by their anomalous Hall response. Our results establish a nonlinear electrical write-read scheme for centrosymmetric altermagnets.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
5 figures, 1 table. Comments and suggestions are welcome
The Role of Electron Correlations in Chirality Induced Spin Selectivity of Molecular Junctions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-23 20:00 EDT
A. Konidena, J. Fransson, L. Kantorovich
The Non-Equilibrium Green’s Function (NEGF) approach is applied to a chain of Hubbard atoms in a helical geometry sandwiched between two leads, one of which is magnetic, to assess what role the electronic correlation effects within the molecule may play in explaining the Chirality Induced Spin Selectivity (CISS) effect. The correlation effects are treated at the level of the self-consistent second Born approximation. Two chiralities, Laevorotatory (L) and Dextrorotatory (D), of the helix, are discussed. Further, we account for spin-orbit coupling (SOC) within the chains using a simplified model of Kane and Mele that exploits next-nearest neighbour interactions intrinsic to a curved geometry. The interaction with the leads is considered within the Wide Band Approximation. We consider the ratio, U/t, of the Hubbard constant U to the hopping t between atomic sites along the chain of up to two, but found very little spin polarisation in our calculations. Even though the spin polarisation factor defined as a relative difference between the largest and smallest total current is found for both enantiomers practically the same, the orientation of the tip’s polarisation required to reach the largest and smallest currents for the two enantiomers differed. It is also found that the qualitative agreement with observations can only be achieved if we account, self-consistently, for the second order of the perturbation theory. The distribution of the spin populations on the chain atoms for different U/t ratios is also discussed. This study concludes that even though accounting for electron-electron interactions are important in understanding spin selectivity within molecular junctions, they cannot be made solely responsible for the high spin polarisation factors observed in experiments.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Three-Dimensional Imaging of High-Density Dislocation Networks and Their Interactions using Multislice Electron Ptychography
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-23 20:00 EDT
Eegene Chung, Anand Ithepalli, Naomi Pieczulewski, Chia-Hao Lee, Steven Zeltmann, Keun-Yeol Park, Celesta S. Chang, Debdeep Jena, David A. Muller
Development of novel devices often involve combining functional materials and substrates, each chosen for particular physical properties such as low-loss or thermal conductivity. This, however, can introduce a large lattice mismatch and high density of structural defects that may limit device performance and reliability by trapping charge or creating leakage pathways. Such is the case for integrating superconducting TiN with a low-loss sapphire substrate. Here we resolve and image the resulting misfit, screw, and threading dislocations in epitaxial TiN on sapphire using the depth-sectioning capabilities of multislice electron ptychography. We find misfit dislocations spaced ~1.6 nm apart and track out-of-plane crossings of misfit dislocations as well as their transitions to threading dislocations, details which are obscured in conventional defect-imaging methods. The ability to correlate specific dislocation types and their interactions in extremely small volumes and at high densities is valuable for understanding structure-property relations even in modern, scaled devices.
Materials Science (cond-mat.mtrl-sci)
22 pages, 3 figures
Entropy-Driven Initiation and Cytoskeletal Viscoelasticity in Endocytosis: An Onsager Variational Framework
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-23 20:00 EDT
Jinjie Liu, Zhongcan Ouyang, Hao Wu
Receptor-mediated endocytosis requires a particle to approach the cell membrane to within a few nanometers before ligand–receptor binding can occur. Existing continuum models often start from an already established contact and do not explicitly describe how crowding particles on the extracellular side influence the distribution of the particle near the membrane. We examine entropic depletion forces as one possible nonspecific contribution to this initial approach. For ideal depletants, the Asakura–Oosawa excluded-volume construction gives an exact depletion potential for the planar geometry before contact. The potential and force vanish continuously at the onset of excluded-volume overlap. This interaction provides a possible contribution to membrane proximity before specific binding, while its extension to curved wrapping geometries requires additional approximation. Within a reduced continuum model, we combine depletion attraction, ligand–receptor binding, membrane deformation, and cytoskeletal viscoelastic dissipation. The viscoelastic contact is formulated through a hereditary integral and a standard linear solid. The kinetic model gives a conditional minimum ligand density for complete engulfment, a finite particle-size window, and a stiffness-dependent upper limit. When the stationary radius lies inside the domain of finite positive wrapping times, the estimated wrapping time has a minimum at a radius that decreases with increasing binding energy density. At fixed viscosity and other independent parameters, the same time approximation predicts slower wrapping as cell stiffness increases. The two positive roots defining the size window merge at a limiting parameter value, which characterizes closure of the admissible size interval. Depletion attraction is interpreted as one possible contribution to particle-membrane association
Soft Condensed Matter (cond-mat.soft), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph), Cell Behavior (q-bio.CB)
14 pages, 3 figures, 2 tables
Membranes 2026, 16(9), 305; including the corrections
A Statistical Analysis of Diffusion Dynamics in Networks
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-23 20:00 EDT
Network diffusion is a well-known model for studying how a quantity in a network propagates to reach a steady state, where its value becomes uniformly distributed across all nodes. Previous studies of network diffusion have mainly focused on the second-smallest eigenvalue of the network Laplacian to determine the timescale associated with the slowest decaying mode. However, this study investigates the eigenspectrum of the network Laplacian in terms of its statistical properties. This method is useful for studying the statistical properties of network diffusion without calculating all eigenvalues, which can be useful for large networks. Additionally, this study introduces a condition under which the system is less diffusive and investigates how changes in the network structure influence the overall diffusion dynamics.
Statistical Mechanics (cond-mat.stat-mech), Other Condensed Matter (cond-mat.other)
Research Square
Emergent phonon synchronization enhances heat transport in graphite
Physical Sciences - Article | Mechanical and structural properties and devices | 2026-09-22 20:00 EDT
Masahiro Nomura, Zhongwei Zhang, Xin Huang, Yangyu Guo, Wanying Liu, Kenji Watanabe, Takashi Taniguchi, Jie Chen, Sebastian Volz
Collective phonon dynamics are fundamental to thermal science, yet remain challenging to control. Here we demonstrate that thermal phonons in van der Waals (vdW) layered graphite can spontaneously self-synchronize, forming a phase-coherent collective state. Combining microscale thermal measurements with atomistic simulations, we reveal a transition from out-of phase to in-phase interlayer vibrations driven by thermal fluctuations. This synchronization induces a redistribution of phonon populations toward low-frequency coherent modes, thereby breaking the classical statistical detailed balance and giving rise to enhanced heat transport beyond conventional particle scattering-based descriptions. We further show that synchronization is governed by the competition between interlayer coupling and dissipative damping, which defines a critical condition for its emergence. Our findings establish phonon synchronization as a collective dynamical mechanism in vdW layered solids, providing a new route to control heat flow by phase coherence.
Research Square:rs-11109940 (2026)
Posted on Research Square and Under Review at Nature Portfolio
Physical sciences/Nanoscience and technology/Nanoscale materials/Graphene/Mechanical and structural properties and devices, Physical sciences/Materials science/Nanoscale materials/Two-dimensional materials
Self-powered InAs nanowire detector arrays for extended-SWIR spectrometry at room temperature
Article | Nanowires | 2026-09-22 20:00 EDT
Lan Fu, Yang Yu, Wei Wen Wong, Zhe Li, Dawei Liu, Jinyuan Chen, Seyed Saleh Mousavi Khaleghi, Yue Bian, Kosala Dhanawansha, Li Li, Hongwei Liu, Xiaoxue Xu, Monica Allen, Jeffery Allen, Hark Hoe Tan, Chennupati Jagadish, Kenneth Crozier, Ziyuan Li, Chaohao Chen
Spectral sensing in the extended shortwave infrared (e-SWIR) is important for molecular analysis, infrared imaging, and machine vision, motivating the development of compact spectrometers for broader applications. However, conventional commercial off the shelf spectrometers in this wavelength region are expensive and bulky due to their reliance on external dispersive optics/filters and/or cryogenic accessories. Other emerging computational spectrometry is based on Si and InGaAs photodetectors that remain focused on the visible and near-infrared, with few detector platforms operating in the e-SWIR regime that simultaneously provides broadband sensitivity, low-noise room-temperature operation and diverse spectral signatures for accurate identification and reconstruction. Here, we report a room-temperature e-SWIR computational spectrometer based on InAs/InP core-shell nanowire photodetector arrays with geometry-encoded spectral responses. The detectors exhibit self-powered broadband photoresponse across the 1-3 μm range, with responsivity up to 0.215 A W-1, detectivity up to 1.6 × 10^9 cm·Hz1/2 W-1, and microsecond response times. The excellent detector performance is leveraged to demonstrate filter-free spectral reconstruction using a compact multipixel photodetector array device. This enables high-accuracy molecular absorption spectrum reconstruction and hyperspectral imaging. Our results indicate that InAs nanowire arrays are a promising platform for compact computational spectrometry and imaging in the e-SWIR at room-temperature.
Research Square:rs-10914779 (2026)
Posted on Research Square and Under Review at Nature Sensors
Physical sciences/Nanoscience and technology/Nanoscale materials/Nanowires, Physical sciences/Nanoscience and technology/Nanoscale devices/Sensors