CMP Journal 2026-04-22
Statistics
Nature: 32
Nature Reviews Materials: 1
Physical Review Letters: 5
arXiv: 73
Nature
Evaluating large language models for accuracy incentivizes hallucinations
Original Paper | Computer science | 2026-04-21 20:00 EDT
Adam Tauman Kalai, Ofir Nachum, Santosh S. Vempala, Edwin Zhang
Large language models sometimes produce confident, plausible falsehoods (“hallucinations”), limiting their reliability1,2. Prior work has offered numerous explanations and effective mitigations such as retrieval and tool use3, consistency-based self-verification4, and reinforcement learning from human feedback5. Nonetheless, the problem persists even in state-of-the-art language models6,7. Here we show how next-word prediction and accuracy-based evaluations inadvertently reward unwarranted guessing. Initially, next-word pretraining creates statistical pressure toward hallucination even with idealized error-free data: using learning theory8,9, we show that facts lacking repeated support in training data (such as one-off details) yield unavoidable errors, while recurring regularities (such as grammar) do not. Subsequent training stages aim to correct such errors. However, dominant headline metrics like accuracy systematically reward guessing over admitting uncertainty. To align incentives, we suggest two additions to the classic approach of adding error penalties to evaluations to control abstention10,11. First, we propose “open-rubric” evaluations that explicitly state how errors are penalized (if at all), which test whether a model modulates its abstentions to stated stakes while optimizing accuracy. Second, since hallucination-specific benchmarks rarely make leaderboards12, we suggest using open-rubric variants of existing evaluations, to reverse their guessing incentives. Reframing hallucination as an incentive problem opens a practical path toward more reliable language models.
Computer science, Statistics
Ubiquitination of glycogen and metabolites in cells and tissues
Original Paper | Homeostasis | 2026-04-21 20:00 EDT
Marco Jochem, Simon A. Cobbold, Craig A. Goodman, Catharina Kueng, Anthony Cerra, Laura F. Fielden, Man Lyang Kim, Philipp Schenk, Ria Agarwal, Xiangyi S. Wang, Simon R. Scutts, Michael Pandos, Lin Tang, Thomas Hermanns, Shane M. Devine, Martin Brzozowski, Yuri Shibata, Niall D. Geoghegan, Catriona A. McLean, Bernhard C. Lechtenberg, Kay Hofmann, Paul Gregorevic, David Komander
Ubiquitin signalling covers a vast realm of protein modifications, yet may still be underestimated due to non-proteinaceous substrates, such as sugars, lipids, and nucleotides1 . The breadth of ubiquitinated non-protein substrates, their abundance, and cellular roles are currently unclear, since current ubiquitinomic and proteomic techniques are blind to non-proteinaceous modifications. We report Non-Protein Ub-clipping (NoPro-clipping) as a mass-spectrometry-based technique that combines ubiquitin clippases with sortase labelling. Targeted and untargeted workflows unveil a vast new canvas of ubiquitin modifications in mammalian cells, and in mouse and human tissues. We find ubiquitinated glycogen in any glycogen-containing tissue in mice, with highest abundance in liver and skeletal muscle. Ubiquitination can deliver glycogen to lysosomes, and leads to reduced glycogen levels. Glycogen ubiquitination is modulated in glycogen storage diseases and regulated by the Met1-polyubiquitin machinery. Strikingly, glycogen depletion in the liver during fasting coincides with elevated glycogen ubiquitination, suggesting that ubiquitin is a previously unknown component of physiological glycogen catabolism. We also reveal ubiquitination of endogenous glycerol and spermine in cells and tissues. NoPro-clipping hence unveils unexpected endogenous non-proteinaceous targets of ubiquitination, broadening the role of ubiquitin from a protein modifier to a general modifier of biomolecules.
Homeostasis, Metabolomics, Proteomics, Ubiquitylation
Caspase 5c amplifies Wnt via APC cleavage to promote intestinal homeostasis
Original Paper | Inflammasome | 2026-04-21 20:00 EDT
Baosen Jia, Yuhua Shi, Yourae Hong, Chongbo Yang, Dylan Roycroft, Shahida Kamal, Sushmita Mukherjee, Beatrix Ueberheide, Alex Grier, Ellen Scherl, Dana Lukin, Randy Longman, Vinita Jacob, Laura Sahyoun, Michael Mintz, Jennifer Claytor, Robbyn Sockolow, Aliza Solomon, Thomas Ciecierega, Arielle Bergman, Kimberley Chien, Kenny Joselin Castro Ochoa, Elliott Gordon, Lily Barash, Melissa Rose, Kelly Garrett, Fabrizio Michelassi, Jeffrey Milsom, David Artis, Gregory Sonnenberg, Caitlin Mason, Victoria Ribeiro de Godoy, Adriana Brcic-Susak, Dario Garone, Chloe Scott, Lexi Tempera, Mavee Witherspoon, Maneeza Bilal, Bing He, Lauretta A. Lacko, Steven M. Lipkin, Sabine Tejpar, J. Magarian Blander
Caspase 5 (CASP5) is a member of the inflammatory caspase family of cysteine proteases that is involved in inflammation and cell death1,2,3. CASP5 shares the highest homology with inflammatory CASP4, but whereas CASP4 is essential for noncanonical inflammasome activation, CASP5 is dispensable4,5,6, and its function remains unknown. Here we show that CASP5 is restricted to the human intestinal epithelium and manifests as three isoforms–CASP5A, CASP5B and CASP5C–among which CASP5C uniquely promotes Wnt signalling, which is essential for epithelial development and regeneration7. We identified dishevelled, which bridges Wnt receptors to the β-catenin destruction complex8, as a prominent CASP5 binding partner in colonic epithelial cells. Dishevelled interacts with the CASP5 catalytic domain through its DEP (dishevelled, EGL-10 and pleckstrin) domain. Lacking the inhibitory caspase activation and recruitment domain (CARD) of CASP5A and CASP5B, CASP5C cleaves the central scaffold protein APC at Asp556 in the Armadillo repeat domain, destabilizing the β-catenin destruction complex and thereby enhancing Wnt signalling. CASP5C expression peaks in transit-amplifying cells, the Wnt-reliant progeny of intestinal stem cells7, whereas CASP5A and CASP5B predominate in mature enterocytes. Endogenous and ectopic CASP5C drive growth of colonic and small intestinal organoids, which is known to require proliferation of transit-amplifying cells9. Furthermore, CASP5C is selectively induced upon intestinal epithelial injury, and its expression is increased in inflammatory bowel disease. Thus, CASP5C is an enzymatic amplifier of Wnt signalling that cleaves APC to sustain proliferation of transit-amplifying cells amid a declining Wnt gradient, safeguarding epithelial renewal. These findings broaden the roles of inflammatory caspases beyond innate immunity, uncovering their contribution to tissue homeostasis.
Inflammasome, Intestinal stem cells
Focal white matter lesions drive grey matter inflammation and synapse loss
Original Paper | Alzheimer’s disease | 2026-04-21 20:00 EDT
Omar de Faria Jr, Stavros Vagionitis, Andrea Lopez-Lopez, Michael Perry, Joseph Jo Yin Wong, Leslie Rodríguez-Kirby, Bastien Hervé, Balazs Viktor Varga, Eneritz Agirre, Sabrina Ghosh, Sebastian Timmler, Mert Yucel, Andrew T. Setley, Kimberley Anne Evans, Tanja Mist Birgisdóttir, Sindri Gíslason, Yan Ting Ng, Courtney Kremler, Helene O. B. Gautier, Yasmine Kamen, Helena Pivonkova, Katrin Volbracht, Felix Hildebrand, Christian A. Cepeda, Javier Rueda-Carrasco, Soyon Hong, George Malliaras, Sabine Dietmann, Gonçalo Castelo-Branco, Ragnhildur Thóra Káradóttir
Focal white matter lesions occur in most neurodegenerative disorders1,2,3. Despite occurring early in disease, white matter lesions are considered to be independent of, or secondary to, grey matter neuroinflammation, synapse loss and altered neuronal activity4,5,6,7. Notably, their functional effect on neuronal circuits remains understudied. To address this, we generated a focal white matter lesion in the rat brain within a clinically relevant, anatomically well-defined circuit, in which these lesions occur in many neurodegenerative disorders8,9,10. Here we show that focal white matter lesions evoke transient neuronal activity changes and microgliosis, with subsequent synapse loss and increased microglial engulfment in the grey matter, which is reversed if myelin regeneration completes. Grey matter microgliosis is often considered to be detrimental; however, we show that it is an integral part of regeneration and is conserved across three distinct mouse circuits and lesioning methods. Preventing these transient changes in the grey matter blocks myelin regeneration in the white matter. Conversely, inducing myelin regeneration failure leads to chronic grey matter neuroinflammation. This recapitulates the low-grade inflammation considered to be a dominant mechanism underlying neurodegeneration7,11,12. Our findings reveal a form of regenerative plasticity coupling white matter integrity to grey matter function, which may underlie multiple neurodegenerative conditions, and highlight the potential of targeting myelin regeneration to prevent chronic neuroinflammation.
Alzheimer’s disease, Multiple sclerosis, Neuroimmunology
Dynamics of genetic and somatic trade-offs in ageing and mortality
Original Paper | Biomarkers | 2026-04-21 20:00 EDT
Danny Arends, David G. Ashbrook, Suheeta Roy, Lu Lu, Zachary Sloan, Arthur G. Centeno, Kurt H. Lamour, João Pedro de Magalhães, Pjotr Prins, Karl W. Broman, Saunak Sen, Sarah J. Mitchell, Michael R. MacArthur, Özlem Altintas Akin, Xiaoxu Li, Amandeep Bajwa, Vivian Diaz, David E. Harrison, Randy Strong, James F. Nelson, Khyobeni Mozhui, Johan Auwerx, Evan G. Williams, Richard A. Miller, Robert W. Williams
DNA variants modulate mortality risks across an entire lifespan but their dynamic age-dependent effects have not been resolved in any species for either sex. Here we mapped variants that shape mortality using an actuarial approach, starting with a base population of 6,438 pubescent mice and ending with 559 survivors that lived beyond 1,100 days of age. Twenty-nine Vita loci influence lifespan with strong age- and sex-specific effects. Most act during distinct stages with polarities that often invert with age, but a minority have consistent age-dependent effects in one or both sexes. A separate set of 30 Soma loci influence correlations between body mass and life expectancy. Nineteen Soma loci mediate higher mortality in larger young mice, whereas 11 mediate lower mortality in larger old mice. All effects are stronger in male mice than in female mice. Vita and Soma loci form epistatic networks split strictly by sex. These findings provide a genetic bridge between evolutionary theories of ageing and molecular mechanisms that can guide interventions to extend healthy lifespan.
Biomarkers, Genetic linkage study, Genetic variation
Astrocytes connect specific brain regions through plastic networks
Original Paper | Astrocyte | 2026-04-21 20:00 EDT
Melissa L. Cooper, Maria Clara Selles, Michael Cammer, Chase Redd, Holly K. Gildea, Joseph Sall, Katelyn E. Chiurri, Philip Cheung, Damian G. Wheeler, Aiman S. Saab, Shane A. Liddelow, Moses V. Chao
Neuronal axons have traditionally been considered to be the primary mediators of functional connectivity among brain regions. However, the role of astrocyte-mediated communication has been largely underappreciated. Astrocytes communicate with one another through gap junctions, but the extent and specificity of this communication remain poorly understood. Astrocyte gap junctions are necessary for memory formation1,2, synaptic plasticity3,4,5, coordination of neuronal signalling6, and closing the visual and motor critical periods7,8. These findings indicate that this form of communication is essential for proper central nervous system development and function. Despite the importance of astrocyte gap junctional networks, studying them has been challenging. Current methods such as slice electrophysiology disrupt network connectivity and introduce artefacts due to tissue damage. Here, we developed a vector-based approach that labels molecules as they are fluxed by astrocyte gap junctions in awake, behaving animals to overcome these limitations. We then used whole-brain tissue clearing9,10 to image these intact, three-dimensional astrocyte networks. We show that multiple astrocyte networks traverse the mouse brain. These networks selectively connect specific regions, rather than diffusing indiscriminately, and vary in size and organization. We observe local networks that are confined to single brain regions and long-range networks that robustly interconnect multiple regions across hemispheres, often exhibiting patterns distinct from known neuronal networks. We also demonstrate that astrocyte networks undergo structural reorganization in the adult brain after sensory deprivation. These findings reveal a mode of communication between distant brain regions that is mediated by plastic networks of gap junction-coupled astrocytes.
Astrocyte, Cellular neuroscience, Light-sheet microscopy, Molecular neuroscience, Super-resolution microscopy
Multicentre gene therapy for OTOF-related deafness followed up to 2.5 years
Original Paper | Clinical trials | 2026-04-21 20:00 EDT
Luoying Jiang, Xiaoting Cheng, Jun Lv, Yuxin Chen, Xiaoyun Chen, Rongqun Zhai, Liqin Zhang, Lei Han, Yiling Zhang, Juhong Zhang, Di Deng, Zhicheng Huang, Qi Cao, Xin Zhang, Daqi Wang, Yizhe Wang, Liheng Chen, Sha Yu, Luo Guo, Bowen Zhang, Hui Wang, Yi Zhou, Liling Dai, Wei Wang, Longlong Zhang, Yanbo Yin, Guiqing Cheng, Ziyi Zhou, Wuqing Wang, Bing Chen, Wei Lu, Hongqun Jiang, Zhiqiang Gao, Dazhi Shi, Yuanping Xiong, Yu Zhao, Wei Yuan, Qin Wang, Guodong Feng, Huawei Li, Zheng-Yi Chen, Yilai Shu
Autosomal recessive deafness 9, caused by OTOF gene mutations, is characterized by severe-to-complete congenital deafness1. Although gene therapy has shown benefits in a small number of patients2,3,4,5, its safety and efficacy across broader age ranges and longer follow-up periods, as well as predictors of treatment outcomes, remain unclear. In this single-arm, multicentre trial conducted at eight centres, 42 participants (aged 0.8-32.3 years) received adeno-associated virus (AAV) serotype 1 carrying a human OTOF coding transgene (AAV1-hOTOF) at three vector dose groups, with up to 2.5-year follow-up. The primary end point was dose-limiting toxicity within 6 weeks. The secondary end point assessed efficacy and adverse events. No dose-limiting toxicities were observed. Grade 3 adverse events included decreased neutrophil count. Hearing was recovered in 90% of participants treated with AAV1-hOTOF, with gradual and stable improvement in auditory brainstem response threshold from greater than 97 ± 1 dB normalized hearing level at baseline to 54 ± 3, 51 ± 3, 50 ± 3 and 42 ± 5 dB normalized hearing level at 1, 1.5, 2 and 2.5 years, respectively, and behavioural audiometry improving from greater than 96 ± 3 dB hearing level at baseline to 37 ± 5 dB hearing level at 2.5 years. Participants aged 0.5-18 years showed greater hearing improvement than adults. A higher number of present distortion product otoacoustic emissions at baseline or biallelic non-truncated OTOF variants was associated with better hearing recovery. Participants with hearing recovery demonstrated gradual improvement in speech perception. AAV1-hOTOF is well-tolerated and efficacious across a broader patient population, with sustained therapeutic benefits for up to 2.5 years. Chinese Clinical Trial Registry registration: ChiCTR2200063181.
Clinical trials, Gene therapy, Inner ear, Translational research
Efficiency-optimized relativistic plasma harmonics for extreme fields
Original Paper | High-harmonic generation | 2026-04-21 20:00 EDT
Robin J. L. Timmis, Colm R. J. Fitzpatrick, Jonathan P. Kennedy, Holly M. Huddleston, Elliott Denis, Abigail James, Chris Baird, Dan Symes, David McGonegle, Eduard Atonga, Heath Martin, Jeremy Rebenstock, John Neely, Jordan Lee, Joshua Redfern, Nicolas Bourgeois, Oliver Finlay, Rusko Ruskov, Sam Astbury, Steve Hawkes, Zixin Zhang, Matt Zepf, Karl Krushelnick, Edward Gumbrell, Paramel Pattathil Rajeev, Mark Yeung, Brendan Dromey, Peter Norreys
Bright harmonic radiation from relativistically oscillating laser plasmas offers a direct route for generating extreme electromagnetic fields. Theory predicts that under optimized conditions, the plasma medium can support strong spatiotemporal compression of laser energy in a coherent harmonic focus (CHF), delivering intensity boosts many orders of magnitude greater than the incident driving laser pulse1,2,3,4. Although diffraction-limited performance5 (spatial compression) and attosecond phase locking6,7,8 (temporal compression) have been demonstrated experimentally, efficient coupling of relativistically intense laser pulse energy into the emitted harmonic cone has not been realized so far. Here we demonstrate that this highly nonlinear interaction can be tailored to deliver the maximum conversion efficiencies predicted from simulations. By fine-tuning the temporal profile of the driving laser on sub-picosecond (<10-12 s) timescales, energies >9 mJ between the 12th and 47th harmonics are observed. These results are in agreement with the theoretically expected efficiency dependence on harmonic order, verifying that optimal conditions have been achieved in the generation process. This is the important final element required to achieve the expected intensity boosts from a CHF in experiments. Although obtaining spatiotemporal compression and optimal efficiency simultaneously remains challenging, the path to realizing extreme optical field strengths approaching the critical field of quantum electrodynamics (the Schwinger limit at >1016 V cm-1 or >1029 W cm-2) is now open, permitting all-optical studies of the quantum vacuum and new frontiers for intense attosecond science.
High-harmonic generation, Laser-produced plasmas
Myosin forces remodel F-actin for mechanosensitive protein recognition
Original Paper | Actin | 2026-04-21 20:00 EDT
Ayala G. Carl, Matthew J. Reynolds, Xiaoyu Sun, Pinar S. Gurel, Donovan Y. Z. Phua, Keith Hamilton, Lin Mei, John W. Watters, Yasuharu Takagi, Alex J. Noble, James R. Sellers, Gregory M. Alushin
Cells interface mechanically with their surroundings through cytoskeleton-linked adhesions1,2, which enable them to sense physical cues that instruct development and drive diseases such as cancer3,4,5. Contractile forces generated by myosin motor proteins6,7 mediate these mechanical signal transduction processes through unknown protein structural mechanisms. Here we show that force generated by myosin elicits structural changes in actin filaments (F-actin) that modulate binding by the mechanosensitive adhesion protein α-catenin8. Using correlative cryo-fluorescence microscopy and cryo-electron tomography, we identify F-actin featuring sinusoidal regions of nanoscale oscillating curvature at cytoskeleton-adhesion interfaces enriched in zyxin, a marker of actin-myosin-generated traction forces9. We introduce a reconstitution system for visualizing F-actin in the presence of myosin forces using cryo-electron microscopy, which reveals morphologically similar F-actin supercoils. In simulations, compressive forces that mimic myosin activity produce supercoils, which can be generated by ensembles of asynchronous motors regardless of their directionality. Three-dimensional reconstruction of supercoils uncovers extensive asymmetric remodelling of the helical lattice of F-actin. This is recognized by α-catenin, which binds cooperatively along individual strands, preferentially engaging interfaces that feature extended inter-subunit distances while simultaneously suppressing rotational deviations to regularize the lattice. In sum, we find that myosin forces can deform F-actin, generating a conformational landscape that is detected and reciprocally modulated by a mechanosensitive protein, providing a direct structural glimpse at active force transduction through the cytoskeleton.
Actin, Cryoelectron microscopy, Cryoelectron tomography, Mechanotransduction
Switchable 2D-3D display through a metasurface lenticular lens
Original Paper | Displays | 2026-04-21 20:00 EDT
Seokil Moon, Joohoon Kim, Youngjin Jo, Juwon Seo, Kyungtae Kim, Seokwoo Kim, Chang-Kun Lee, Junsuk Rho
Three-dimensional (3D) displays provide immersive visuals by delivering depth cues, making them valuable for applications such as interactive media1,2. To enhance practicality, 2D-3D switchable displays offer the flexibility to toggle between high-resolution 2D and immersive 3D modes in a single device3,4. Here we propose a full-colour 2D-3D switchable light-field display powered by a metasurface lenticular lens (MLL). The MLL switches its focal behaviour on the basis of the polarization of incident light, serving as the core mechanism for 2D-3D mode transition. The MLL is designed with a high numerical aperture, enabling a notably wider field of view of 100° while maintaining an ultrathin profile of just 1.2 mm. A large-area MLL with an active area of 25 cm2 is fabricated and seamlessly integrated as a dual-dimension switchable optics device, demonstrating the scalability of the approach for wide-area display applications. The fabricated device, when simply mounted onto an organic light-emitting diode display panel, successfully demonstrates clear 2D and 3D images, along with the active switching functionality enabled by applied voltage. These results highlight a promising solution for next-generation display technologies in both consumer electronics and commercial applications.
Displays, Metamaterials, Nanophotonics and plasmonics, Photonic devices, Surface patterning
Netrin1 blockade alleviates resistance to chemotherapy in pancreatic cancer
Original Paper | Adaptive clinical trial | 2026-04-21 20:00 EDT
Gael Roth, Pascal Artru, Olivier Bouche, Nicolas Williet, Julien Ghelfi, Anthony Turpin, Astrid Lievre, Jean-Frédéric Blanc, Camille Evrard, Jean-Baptiste Bachet, Pauline Parent, Marc Manceau, Matthieu Roustit, Anna Borowik, Victoire Granger, Aurélie Durand, Christelle d’Engremont, Edouard Girard, Mircea Chirica, Nicolas Braissand, Nicolas Rama, Eugénie Modolo, Hector Hernandez-Vargas, Elise Georges, Jean-Yves Scoazec, Jerome Cros, Sébastien Hazard, Benjamin Ducarouge, Thomas Decaens, Agnès Bernet, Patrick Mehlen
Netrin1, a developmental cue, is a master regulator of tumour epithelial-to-mesenchymal transition (EMT)1, a mechanism that is known to drive resistance to chemotherapy2. A netrin1 antibody (NP137)3 has been shown to inhibit tumour EMT in preclinical1 and clinical4 settings. In animal models of pancreatic cancer, netrin1 and its receptor neogenin have been shown to promote tumour progression5, EMT5 and metastasis6. Here we report the results of a phase 1b study that assesses the combination of NP137 with modified FOLFIRINOX (mFOLFIRINOX) in first line patients with locally advanced pancreatic cancer (ClinicalTrials.gov: NCT05546853). Forty-three patients were enrolled and received mFOLFIRINOX plus NP137 every other week for up to 12 cycles. NP137 was well tolerated. Median progression-free survival (PFS) was 10.85 months (95% confidence interval, 10.03-15.61) and median overall survival was 16.43 months (95% confidence interval, 12.75-non-reached), with 21 patients remaining alive at the time of data cut-off. Post-therapy conversion surgery occurred in 23% of patients. Laser capture microdissection was performed on pre-therapeutic biopsies and surgical specimens. Microbulk RNA sequencing confirmed that the main pathway that was down-regulated with the combination of mFOLFIRINOX plus NP137 was EMT. Moreover, survival outcomes were extended for patients with tumour cells that expressed high levels of the netrin1 receptor neogenin–median PFS 15.65 months in neogenin-high versus 10.22 months in neogenin low. Our results support the idea that netrin1 blockade alleviates resistance to chemotherapy by inhibiting EMT, particularly in neogenin-high pancreatic cancer.
Adaptive clinical trial, Cancer therapeutic resistance, Pancreatic cancer, Translational research
Non-equilibrium condensation of the first Solar System solids
Original Paper | Early solar system | 2026-04-21 20:00 EDT
Sébastien Charnoz, Jérôme Aléon, Marc Chaussidon, Paolo A. Sossi, Yves Marrocchi, Patrick Franco
Primitive meteorites (chondrites) consist of an out-of-equilibrium assemblage of minerals formed during the assembly of our solar nebula1. The conditions under which their precursors condensed remain unclear as a result of subsequent reprocessing in the protoplanetary disk or in asteroidal parent bodies. Chondrites are classified into three main classes–enstatite, ordinary and carbonaceous–and these are distinguished by different bulk composition and oxidation state2. Although equilibrium condensation models explain the composition of some of their refractory components3,4, they do not explain the emergence of three mineralogical classes. Moreover, the low pressures, steep temperature gradients and short dynamical transport timescales in forming protoplanetary discs probably hindered equilibrium. Here we test the hypothesis that chondrite precursors formed via kinetic non-equilibrium condensation. Using a new time-dependent condensation model, we show that varying the cooling rate and pressure produce only three types of mineralogies. Departure from equilibrium yields increasingly oxidized and hydrous mineralogies. When projected into a Urey-Craig diagram, the predicted mineralogical types fall close to the redox states of enstatite, ordinary and carbonaceous chondrites. These results suggest that the mineralogical diversity of chondrites may reflect, in part, local condensation kinetics, offering an alternative to large-scale variations of oxidation conditions.
Early solar system, Mineralogy
A pro-carcinogenic bacterial toxin binds claudin-4 to cleave E-cadherin
Original Paper | Bacterial toxins | 2026-04-21 20:00 EDT
Maxwell T. White, Kang Wang, Hailong Zhang, Ulrich Eckhard, Karthik Hullahalli, Jason Chen, Shaoguang Wu, Abby L. Geis, Jie Zhang, Jessica Queen, F. Xavier Gomis-Ruth, Matthew K. Waldor, Min Dong, Cynthia L. Sears
The human colon is colonized by trillions of bacteria that play substantial roles in human health and disease1. Epidemiological and experimental studies suggest that certain colonic bacteria can stimulate the development and progression of colorectal cancer2. One such bacterium, enterotoxigenic Bacteroides fragilis, drives colon tumour formation through the action of a single toxin, the B. fragilis toxin (BFT)3,4. BFT is a metalloprotease that binds to a colonic epithelial cell receptor and causes cleavage of the E-cadherin ectodomain, leading to epithelial barrier disruption, inflammation and increased cellular proliferation4,5,6. However, the identity of the BFT receptor is unknown and the molecular mechanism of BFT-initiated E-cadherin cleavage is not well understood. Here we identify claudin-4 as a BFT receptor through a genome-wide CRISPR screen and demonstrate that claudin-4 binding promotes BFT-mediated cleavage of cell surface E-cadherin. Our work both sheds light on BFT’s mechanism of action and opens avenues for the development of anti-BFT therapies, which may prove useful for colorectal cancer prevention and treatment of acute enterotoxigenic B. fragilis infection.
Bacterial toxins, Colorectal cancer, Membrane proteins, Microbiome, Proteases
Electronic origin of reorganization energy in interfacial electron transfer
Original Paper | Electrochemistry | 2026-04-21 20:00 EDT
Sonal Maroo, Leonardo Coello Escalante, Yizhe Wang, Matthew P. Erodici, Jonathon N. Nessralla, Ayana Tabo, Takashi Taniguchi, Kenji Watanabe, Ke Xu, David T. Limmer, D. Kwabena Bediako
Electron transfer (ET) reactions underpin energy conversion and chemical transformations in both biological1,2 and abiological3,4,5 systems. The efficiency of any ET process relies on achieving a desired ET rate within an optimal driving force range. Marcus theory6,7 provides a microscopic framework for understanding the activation free energy–and therefore the rate–of ET in terms of a key parameter: the reorganization energy. For electrified solid-liquid interfaces, it has long been conventionally understood that only factors in the electrolyte phase are responsible for determining the reorganization energy and that the electronic density of states (DOS) of the electrode only serves to dictate the number of thermally accessible channels for ET5,8,9,10,11,12. Here we show instead that the electrode DOS plays a central role in governing the reorganization energy, far outweighing its conventionally assumed role. Using atomically layered heterostructures, we tune the DOS of graphene and measure outer-sphere ET kinetics. We find the ensuing variation in ET rate arises from strong modulation in a reorganization energy associated with image potential localization in the electrode. Here we redefine the traditional paradigm of heterogeneous ET kinetics, revealing a deeper role of the electrode electronic structure in interfacial reactivity.
Electrochemistry, Electron transfer, Two-dimensional materials
Glycerol-driven TNAP activation in thermogenesis and mineralization
Original Paper | Dental diseases | 2026-04-21 20:00 EDT
Mohammed Faiz Hussain, Shreya S. Krishnan, Brittany L. Carroll, Bozena Samborska, Aisha Mousa, Alice Williamson, Maria Delgado-Martin, Bindu Y. Srinivasu, Jakub Bunk, Janane F. Rahbani, Abel Oppong, Anna Roesler, Zafir Kaiser, Mina Ersin, Qiaoqiao Zhang, Maria Guerra Martinez, Abhirup Shaw, Jonathan Cheng, Hannah Klemets, Katalin Kocsis Illes, Victoria E. DeMambro, Clifford J. Rosen, José Luis Millán, Thomas E. Wales, Claudia Langenberg, Marc D. McKee, Alba Guarné, Lawrence Kazak
Tissue-nonspecific alkaline phosphatase (TNAP) promotes skeletal mineralization by hydrolysing pyrophosphate1 and has been linked to uncoupling protein 1 (UCP1)-independent adipocyte thermogenesis through the futile creatine cycle through phosphocreatine hydrolysis2,3. Despite TNAP’s broad physiological roles, endogenous regulators of its activity have not been defined. Furthermore, the activation mechanism of UCP1-independent thermogenesis has remained unresolved. Here we identify glycerol as an allosteric activator of TNAP. Glycerol binds to a surface pocket distal to the active site, which we term the glycerol pocket, to enhance TNAP activity. Using biophysical, structural, bioenergetic and physiological approaches, we show that the glycerol pocket is required for TNAP-driven thermogenesis. Through this mechanism, TNAP activates the futile creatine cycle, acting as a physiological complement to UCP1. The glycerol pocket is likewise required for optimal osteoblast-regulated mineralization. Human missense variants in this site reduce TNAP-dependent mineralization in vitro and are associated with lower alkaline phosphatase activity and bone mineral density, providing genetic evidence that its disruption impairs skeletal physiology.
Dental diseases, Enzyme mechanisms, Preclinical research
Chromosomal fusions trigger rediploidization of autopolyploid genomes
Original Paper | Chromosomes | 2026-04-21 20:00 EDT
Chuanshuai Xie, Zitu Ma, Chaowei Zhou, Kexin Ma, Haoyu Wang, Jiahong Wu, Yan Zhou, Yongrui Lu, Da Ji, Xuedie Gu, He Gao, Junting Li, Suxing Fu, Weiqiang Li, Zhaofang Han, Shijun Xiao, Fei Liu, Benhe Zeng, Sheng’ao Chen, Jiangong Niu, Tao Zhang, Jian Shen, Chunna Liu, Jing Luo, Daniel J. Macqueen, Axel Meyer, Haiping Liu, Luohao Xu
The ancestor of all vertebrates is thought to have undergone autopolyploid whole-genome duplication (WGD)1,2, doubling the genetic raw material for evolutionary diversification3,4,5. However, we still do not understand the first steps of rediploidization that followed, required for the emergence and divergence of duplicated genes (ohnologues) created by WGD6,7. Consequently, how the functional potential created by autopolyploidy becomes realized during evolution remains unclear. Snow carps (Schizothoracine) have a history of recent WGDs and evolved high-altitude adaptations8,9,10, making these fish a particularly suitable system to study the early stages and consequences of rediploidization. Here genomic data from all snow carp genera reveal their autopolyploid origin, including tetraploids, hexaploids and one icosaploid (20n). We present haplotype-resolved genomes for two snow carp species (Schizopygopsis younghusbandi and Schizothorax curvilabiatus) from divergent lineages, revealing a single ancestral autotetraploidy event. Comparative genomic, meiotic pairing and allele composition analyses indicate that unbalanced chromosome fusions were responsible for the transition from tetrasomic to disomic inheritance, creating genomic regions harbouring diploid ohnologue pairs, with non-rearranged chromosomes remaining tetraploid. This study suggests that this mechanism initiated rediploidization and documents its early chromosomal and genomic consequences. It starts at chromosome fusion sites and expands outwards towards chromosomal arms, a process that remained incomplete post-speciation, leading to a mixture of ancestral and lineage-specific ohnologue divergence on highly syntenic chromosomes.
Chromosomes, Evolutionary genetics, Molecular evolution, Polyploidy
Printable meta-assemblies enable synergetic colouration
Original Paper | Adaptive optics | 2026-04-21 20:00 EDT
Kaixuan Li, Jianfeng Chen, Huizeng Li, An Li, Xiaoyu Hou, Sujuan Ma, Maoxiong Zhao, Shengnan Chen, Quan Liu, Dongyu Yang, Rujun Li, Xiao Deng, Renxuan Yuan, Luanluan Xue, Wanling Liu, Ming Yang, Zhimei Jia, Mingzhu Li, Joel K. W. Yang, Cheng-Wei Qiu, Yanlin Song
Biological systems achieve multifunctionality through the synergy of nanoscale building blocks and microscale morphological hierarchies, a multiscale structure that would be advantageous to implement in metamaterials1,2,3,4,5. However, most artificial optical systems can only be fabricated on a single scale, facing the challenges of limited scalability, inadequate tunability and monotonous functionality6,7,8. Here we present a printable meta-assembly strategy that enables the fabrication of multiscale hierarchical optical architectures through continuous roll-to-roll (R2R) manufacturing. The meta-assembly comprises low-cost polystyrene (PS) nanoparticles periodically embedded in a polydimethylsiloxane (PDMS) matrix, forming a nanolattice-based microconcave optical interface that enables precise integration of guided-wave and reflected-wave dispersion and interference9,10,11,12. By optical coupling, distinct synergetic colouration is explored and experimentally realized with high designability and tunability. Overcoming scalability constraints, metre-scale meta-assembly prints with single-pixel customization can be rapidly fabricated from the nanoscale building blocks, spanning seven orders of magnitude in length. The vibrant prints exhibit controlled colour separation and integration performances, along with environmental stability, showing potential for eco-friendly colouration, intelligent displays and information security. This work provides a versatile methodology for biologically inspired metamaterial construction by means of multiscale photonics research.
Adaptive optics, Biomimetic synthesis, Metamaterials, Structural properties, Synthesis and processing
H2O2 repurposes plant O2 sensing to regulate post-hypoxia responses
Original Paper | Flooding | 2026-04-21 20:00 EDT
Salma Akter, Monica Perri, Mikel Lavilla-Puerta, Sophie Lichtenauer, Yuming He, Vinay Shukla, Laura Dalle Carbonare, Yuri Telara, Daai Zhang, Beatrice Ferretti, Dona M. Gunawardana, William K. Myers, Pedro Barreto, Beatrice Giuntoli, Markus Schwarzländer, Emily Flashman, Francesco Licausi
Understanding plant molecular responses to flooding is crucial for strategies to increase resilience. Plants respond to submergence-induced low oxygen (hypoxia) through decreased plant cysteine oxidase (PCO) activity, which stabilizes group VII ethylene response factors (ERFVIIs), master regulators of metabolic and anatomic acclimation responses1,2,3,4. Rapid reoxygenation on desubmergence induces a burst of reactive oxygen species (ROS) generation and metabolic reconfiguration5,6; however, how plants mitigate this post-hypoxic stress to facilitate submergence recovery has remained unknown. Here we report that ERFVIIs are also important in post-submergence recovery, remaining stable upon reoxygenation through ROS-mediated PCO inhibition. Stabilized ERFVIIs are retained at hypoxia-responsive promoters, becoming repressors of typical hypoxia marker genes but upregulators of genes involved in ROS homeostasis and oxidative stress protection. Our findings suggest that PCOs and ERFVIIs integrate signals from both oxygen and ROS to coordinate ERFVII stability through submergence-induced hypoxia and desubmergence stress to promote plant survival and recovery.
Flooding, Oxidoreductases
Heart-nosed bat alphacoronaviruses use human CEACAM6 to enter cells
Original Paper | Microbiology | 2026-04-21 20:00 EDT
Giulia Gallo, Antonello Di Nardo, Doreen Lugano, Adam J. Roberts, Bernadette Ataku Kutima, Moses Okombo, Aghnianditya Kresno Dewantari, Florence M. M. Buckley, Gavin J. Wright, James Nyagwange, Bernard Agwanda, Stephen C. Graham, Dalan Bailey
Identifying viruses with zoonotic potential on the basis of their ability to enter human cells is a critical component of pandemic prediction, prevention and preparedness. Here using a computational approach that retains maximum phylogenetic diversity, we selected an optimal subset of alphacoronavirus spike proteins to screen against broad coronavirus receptor libraries. Most of the selected spike proteins did not use any of the established coronavirus receptors. However, the pseudotyped spike protein of Cardioderma cor (heart-nosed bat) coronavirus KY43 (CcCoV-KY43) could enter human cells. Using a recombinant CcCoV receptor-binding domain (RBD) and a human receptor screening platform, we identified direct interactions with the human CEACAM proteins CEACAM3, CEACAM5 and CEACAM6. Overexpression of human CEACAM6–a protein widely expressed in the human lung–conferred permissivity to otherwise refractory human cells. A crystal structure showed that the RBD binds the amino-terminal IgV-like domain of human CEACAM6. Immune surveillance studies using sera of individuals from the Taveta region of Kenya, where CcCoV-KY43 was identified, did not show significant evidence of recent spillover. Wider characterization of alphacoronaviruses related to CcCoV-KY43 showed that human CEACAM6 is used by two other CcCoVs collected in Kenya. Moreover, there was more restricted nonhuman CEACAM6 tropism for viruses isolated from Rhinolophus bats from Russia and China. Thus, alphacoronaviruses that use CEACAM6 are probably geographically widespread, and viruses from East Africa show potential for transmission to humans.
Microbiology, Virology, Virus-host interactions
Symmetry classification of magnetic orders using oriented spin space groups
Original Paper | Electronic properties and materials | 2026-04-21 20:00 EDT
Yuntian Liu, Xiaobing Chen, Yutong Yu, Jesús Etxebarria, J. Manuel Perez-Mato, Qihang Liu
Magnetism has seen substantial progress in recent decades, driven largely by its potential for next-generation storage devices. However, the classification of magnetic orders, even for fundamental concepts such as ferromagnetism (FM) and antiferromagnetism (AFM), remains a topic of active evolution, particularly with the discovery of unconventional magnetic materials and advances in antiferromagnetic spintronics1,2,3,4. Here we present a classification of magnetic order using the state-of-the-art spin space group (SSG) theory5,6,7,8,9,10,11. On the basis of whether the net spin magnetization is constrained to zero by the SSG framework, we systematically categorize magnetic orders into FM (including ferrimagnetism) and AFM. We further introduce an ‘oriented spin space group’ (OSSG) description, that is, a SSG with a fixed magnetic orientation, thereby unifying the SSG and magnetic space group (MSG)12,13,14 frameworks. This approach clearly reveals the symmetry-breaking pathway induced by spin-orbit coupling (SOC). On the basis of the proposed group framework, we identify a distinct magnetic phase, termed spin-orbit magnetism (SOM), in which the net spin magnetization is induced by SOC. Our work provides a comprehensive symmetry-based perspective for classifying magnetic order, offering fresh insights into unconventional magnets and broad applicability in spintronics and quantum materials design.
Electronic properties and materials, Magnetic properties and materials
Mechanically driven Li dendrite penetration in garnet solid electrolyte
Original Paper | Batteries | 2026-04-21 20:00 EDT
Yuwei Zhang, Soroush Motahari, Eric V. Woods, Stefan Zaefferer, Peter Schweizer, Zhiyuan Zhang, Yuqi Liu, Baptiste Gault, Franz Roters, Dierk Raabe, Christina Scheu, Yug Joshi, Siyuan Zhang, Chuanlai Liu, Gerhard Dehm
All-solid-state batteries promise improved safety and higher energy density by replacing flammable liquid electrolytes and graphite anodes with solid electrolytes and lithium metal1,2,3,4. However, the penetration of soft lithium dendrites into hard ceramic electrolytes remains a substantial obstacle to realizing all-solid-state lithium metal batteries5,6,7. The mechanism by which mechanically soft lithium dendrites fracture hard ceramic electrolytes remains under debate7,8,9,10 owing to the challenges of characterizing nanoscale lithium distribution and its microstructure at the dendrite tip11. Here we investigate the fracture process driven by lithium dendrites in garnet electrolytes using multiscale cryogenic electron microscopy and micromechanical fracture models. We directly visualize lithium dendrites fully filling nanoscale crack tips and extending into micrometre-scale cracks. Limited crystal lattice rotation and plasticity in lithium dendrites indicate that the plated lithium generates substantial hydrostatic stress, which induces tensile stress in the solid electrolyte and drives both intergranular and transgranular fracture. By contrast, the region ahead of the lithium dendrite tip shows no measurable enrichment of lithium or lithium metal nuclei. The mechanically driven lithium penetration in garnet solid electrolyte can be redirected by geometrically engineered voids in the electrolyte, thus mitigating short-circuiting. Our findings suggest that grain boundary toughening and defect engineering are effective strategies for designing dendrite-resistant solid electrolytes.
Batteries
Early fibrotic niches establish tumour-permissive microenvironments
Original Paper | Cancer microenvironment | 2026-04-21 20:00 EDT
Erik C. Cardoso, Hyeyoung Lee, Frances J. England, Hyunjin Cho, Robin Lu, Sagar S. Varankar, Moo Suk Park, Natasha Rekhtman, Bon-Kyoung Koo, Benjamin D. Simons, Jinwook Choi, Joo-Hyeon Lee
Pathologic transformation represents a critical yet poorly defined window during which mutant epithelial stem cells actively construct the microenvironment that enables tumour initiation1,2. Here using integrated single-cell, spatial and functional analyses, we define the earliest multicellular events that licence this transition following oncogenic activation in the lung. KrasG12D-mutant alveolar type II cells rapidly adopt regenerative-like states that act as signalling hubs, orchestrating coordinated stromal and immune reprogramming while enhancing epithelial plasticity. Through secretion of amphiregulin, mutant epithelial cells activate EGFR signalling in adjacent fibroblasts, inducing a fibrotic, injury-like programme. Reprogrammed fibroblasts, in turn, expand and reprogramme alveolar macrophages, amplifying inflammatory signalling and reinforcing epithelial plasticity. These reciprocal interactions establish a self-sustaining epithelial-stromal-immune circuit that generates a tumour-permissive niche before malignant outgrowth. Disruption of the amphiregulin-EGFR axis prevents early niche formation and abrogates tumour initiation. Conservation of this programme in KRASG12D-inducible human alveolar organoids and early-stage lung adenocarcinoma tissues identifies epithelial-microenvironment communication as a therapeutically actionable vulnerability and suggests that intercepting niche formation may prevent progression to treatment-resistant disease.
Cancer microenvironment, Regeneration, Stem-cell niche
The evolutionary history and unique genetic diversity of Indigenous Americans
Original Paper | Anthropology | 2026-04-21 20:00 EDT
Marcos Araújo Castro e Silva, Kelly Nunes, Maíra R. Ribeiro, Hemanoel Passarelli-Araujo, Renan Barbosa Lemes, Lilian Kimura, Putira Sacuena, Carlos Eduardo G. Amorim, Maria Cátira Bortolini, José Geraldo Mill, João Farias Guerreiro, Chiara Barbieri, Diana Iraíz Hernández-Zaragoza, Antonia Walter, Trija Nag Chowdhury, Daniela Macías-Herrera, Julio César Lara-Riegos, Oana Del Castillo-Chávez, Camilo Zurita, Ana María Tito-Álvarez, Emilia Vásquez-Domínguez, María Ermila Moo-Mezeta, Julio César Torres-Romero, Abraham Aguilar-Campos, Ricardo Serrano-Osuna, Maria Laura Parolín, Claudio M. Bravi, Virgínia Ramallo, Graciela Bailliet, Susana Revollo, José R. Sandoval, Ricardo Fujita, Rodrigo Barquera, Fabrício R. Santos, David Comas, Tábita Hünemeier
Indigenous peoples of America represent the last principal expansion of humans across the globe1, yet their genetic history remains one of the least explored2. Although these populations have inhabited the continent for thousands of years3, their evolutionary history remains largely unresolved4,5, owing to the limited availability of genomic data. Here we present data on 128 high-coverage Indigenous American genomes and show they harbour extensive and previously uncharacterized genetic diversity, reflecting at least three dispersals into South America, followed by regional differentiation and long-term continuity. We identified widespread natural selection signals in genes associated with immunity, metabolism, reproduction and development, which were shaped by adaptation to diverse environmental conditions. Notably, several genomic regions exhibit a remarkable allele sharing with Australasian populations, probably originating from an ancient admixture event and partly maintained by selection for more than 10,000 years. We also detected distinct contributions from archaic humans with adaptive introgression affecting key biological functions. The limited overlap between the regions of Australasian affinity and archaic ancestry indicates independent evolutionary origins of these signals. These findings challenge simplified models of continental settlements and show a more dynamic and complex evolutionary history for the Indigenous peoples in America.
Anthropology, Evolutionary genetics, Genetic variation, Population genetics
Transposable elements are driving rapid adaptation of Enterococcus faecium
Original Paper | Bacterial evolution | 2026-04-21 20:00 EDT
Matthew P. Grieshop, Aaron A. Behr, Sierra Bowden, Jordan D. Lin, Marco Molari, Gabriella ZM Reynolds, Erin F. Brooks, Boryana Doyle, Ashley A. Moore, Guillermo Rodriguez-Nava, Jorge L. Salinas, Niaz Banaei, Ami S. Bhatt
Bacterial pathogens adapt rapidly to clinical and within-host selective pressures1. Insertion sequences (IS) are transposable elements that can contribute to pathogenic adaptation2, but their activity and consequences in contemporary clinical populations are not well characterized. Here, combining large-scale genomic surveys with long-read sequencing of clinical isolates and longitudinal gut metagenomes, we quantify pathogen IS dynamics from global patterns to within-host evolution. Across 19,485 publicly available high-contiguity ESKAPEE pathogen genomes, Enterococcus faecium genomes are the most IS dense, dominated by replicative ISL3 family elements, which have proliferated in clinical lineages over the past 30 years. We find extensive chromosomal structural variation, largely involving ISL3, within a new single-hospital collection of bloodstream isolates. Long-read metagenomic sequencing of 28 longitudinal stool samples from 12 haematopoietic cell transplantation (HCT) recipients demonstrates within-host IS dynamics and their regulatory consequences. In one patient, an ISL3 insertion upstream of a folate transporter formed a strong promoter, increasing transcription and improving relative fitness under folate limitation. Enhanced folate scavenging may enable E. faecium to thrive in the setting of microbiome collapse, which is common in HCT and other critically ill patients3. Together, these results show that a recent ISL3 expansion is driving rapid evolution in healthcare-associated E. faecium, with consequences for its metabolic fitness that may help explain its increasing clinical burden. Several other pathogens also show elevated IS loads in our survey, which suggests that IS expansion-mediated evolution might be more broadly relevant.
Bacterial evolution, Clinical microbiology
Decade-long warming accelerates antibiotic resistance in grassland soils
Original Paper | Climate-change impacts | 2026-04-21 20:00 EDT
Linwei Wu, Da-Shuai Mu, Jing An, Yanan Wang, Xiaomin Fan, De-Chen Lu, Ya Zhang, Yinan Xie, Jonathan Michael, Daniel Curtis, Yupeng Fan, Yajiao Wang, Xue Guo, Qichao Tu, Qingyun Yan, Qun Gao, Zhili He, Ye Deng, Kai Xue, Liyou Wu, Daliang Ning, Xuanyu Tao, Yunfeng Yang, Jizhong Zhou
Soils are critical reservoirs of antibiotic-resistance genes (ARGs)1,2, which are strongly shaped by microbial interactions and environmental conditions and are therefore highly sensitive to disturbance2,3,4,5,6. Although climate warming is recognized as one of the most significant disturbances to microbial communities and their functions7,8,9,10, its impacts on soil resistomes remain poorly understood. Here we investigated the effects of decade-long experimental warming on ARGs in grassland soils using integrated experimental and computational approaches. Our results revealed that ARG abundance substantially increased (23.9%) under warming–particularly glycopeptide- and rifamycin-resistance genes. Warming specifically enriched Actinomycetota hosts, including various potential plant pathogens, and enhanced ARG mobility. Large-scale unprecedented isolates-based phenotypic analyses also validated that warming increased bacterial resistance to multiple antibiotics. Further mechanistic analyses revealed that warming increased ARG abundance primarily through co-selection of resistance genes physically linked to adaptive traits (for example, thermal tolerance and nitrogen assimilation) and positive selection for thermal tolerance genes, which could be further amplified via horizontal gene transfer. Together, these findings convincingly demonstrate that climate warming substantially accelerates soil antibiotic resistance at genomic, ecological and evolutionary levels, with broad implications for public health and environmental sustainability in a warming world.
Climate-change impacts, Microbial ecology, Soil microbiology
Punctuated decline of human cooperation
Original Paper | Economics | 2026-04-21 20:00 EDT
Nicholas Sabin, David Klinowski, Felix Reed-Tsochas
Human cooperation is dynamic and often declines even under favourable conditions1,2,3,4. Many prevailing theories explain the decrease of cooperation in terms of strategic behaviour or learning, framed as evidence of rational behaviour or progression towards rationality5,6,7,8,9. Here we show that a key source of long-term decline derives from deviations from rational behaviour that systematically vary over time. We analyse a natural social dilemma in the field–that is, group lending in Sierra Leone–tracking cooperative dynamics over a five-year period. Borrowers enter a joint-liability contract, structured so that if the group loan is not repaid in full, all members lose access to future credit10. This produces a threshold social dilemma with incentives to free-ride11,12. The dataset includes 47,931 group payments made by 7,108 borrowers, augmented with a two-stage cluster sample of semi-structured interviews. We find a statistically robust pattern of punctuated decline driven by behavioural mechanisms13. Cooperation rates start out high but gradually decline due to decreases in group members’ cooperative motivation and effort. Sharp rebounds occur when loans are restarted and clients resensitized to their cooperative responsibilities, even though the group membership and dilemma structure are largely unchanged. This pattern persists over the five-year observation window, but with each successive restart the subsequent decline is more rapid. The findings have direct implications for preventing behavioural decline in cooperative programmes and institutions.
Economics, Human behaviour, Sociology
Outplaying elite table tennis players with an autonomous robot
Original Paper | Computer science | 2026-04-21 20:00 EDT
Peter Dürr, Mireille El Gheche, Guilherme Jorge Maeda, Nobuhiko Mukai, Naoya Takahashi, Stefan Heusser, Hamdi Sahloul, Yamen Saraiji, Pavel Adodin, Yin Bi, Sam Blakeman, Christian Conti, Dunai Fuentes Hitos, Yunpu Hu, Farshad Khadivar, Raphaela Kreiser, Luz Martinez, Fabian Schilling, Ricardo Tapiador Morales, Guillem Torrente, Mario Ynocente Castro, Lison Abecassis, Alberto Giammarino, Yu-Ting Huang, Yannik Nagel, Andrea Scotti, Alexander Sigrist, Tiago Silva, Etienne Walther, Jengyan Wong, Bilan Yang, Asude Aydin, Divij Grover, Apurv Saha, Valentina Cavinato, Takekazu Kakinuma, Taishi Kunori, Valentin Monferrato, Stefan Richter, Stefanos Charalambous, Simon Guist, Mads Alber Kuhlmann-Jorgensen, Lorenzo Miele, Agis Politis, Mattia Scardecchia, Hiroaki Kitano, Peter R. Wurman, Peter Stone, Michael Spranger
Artificial intelligence (AI) systems now challenge or surpass human experts in many computer games1,2. Physical and real-time sports such as table tennis, however, remain a major open challenge because of their requirements for fast, precise and adversarial interactions near obstacles and at the edge of human reaction time3. Here we present Ace, to our knowledge the first real-world autonomous system competitive with elite human table tennis players. Ace addresses the challenges of physical real-time interaction through a new, high-speed perception system using event-based vision sensors4, and a new control system based on model-free reinforcement learning, as well as state-of-the-art high-speed robot hardware. Evaluated in matches against elite and professional players under official competition rules, Ace achieved several victories and demonstrated consistent returns of high-speed, high-spin shots. These results highlight the potential of physical AI agents to perform complex, real-time interactive tasks, suggesting broader applications in domains requiring fast, precise human-robot interaction.
Computer science, Electrical and electronic engineering, Mechanical engineering
Phonon Hall viscosity and the intrinsic thermal Hall effect of α-RuCl3
Original Paper | Magnetic properties and materials | 2026-04-21 20:00 EDT
Avi Shragai, Ezekiel Horsley, Subin Kim, Young-June Kim, B. J. Ramshaw
The thermal Hall effect has been observed in a wide variety of magnetic insulators1,2,3,4,5,6,7,8,9, yet its origins remain controversial. Although some studies attribute the effect to intrinsic mechanisms10,11,12,13,14, such as heat carriers with Berry curvature, others propose extrinsic mechanisms15,16,17, such as heat carriers scattering off crystal defects. Even the nature of the heat carriers is unknown: magnons, phonons and fractionalized spin excitations have all been proposed. Resolving these issues is essential for the study of quantum spin liquids, and particularly for α-RuCl3, in which a quantized thermal Hall effect has been attributed to Majorana edge modes18,19. Here we use ultrasonic measurements of the acoustic Faraday effect to demonstrate that the phonons in α-RuCl3 have Hall viscosity–a non-dissipative viscosity that rotates phonon polarizations and deflects phonon heat currents. We show that phonon Hall viscosity produces an intrinsic thermal Hall effect that quantitatively accounts for a substantial fraction of the measured thermal Hall effect in α-RuCl3: the thermal Hall effect in α-RuCl3 is due to phonons, and it is intrinsic. More broadly, we demonstrate that the acoustic Faraday effect is a powerful tool for detecting phonon Hall viscosity and the associated phonon Berry curvature, offering a new way to uncover and study exotic states of matter that elude conventional experiments.
Magnetic properties and materials, Phase transitions and critical phenomena
Hybrid calculation of hadronic vacuum polarization in muon g - 2 to 0.48%
Original Paper | Phenomenology | 2026-04-21 20:00 EDT
A. Boccaletti, Sz. Borsanyi, A. Cotellucci, M. Davier, Z. Fodor, F. Frech, A. Gérardin, D. Giusti, A. Yu. Kotov, L. Lellouch, Th. Lippert, A. Lupo, B. Malaescu, S. Mutzel, A. Portelli, A. Risch, M. Sjö, F. Stokes, K. K. Szabo, B. C. Toth, G. Wang, Z. Zhang
For 50 years, the standard model of particle physics has been very successful in describing subatomic phenomena. In the past quarter of a century, this was challenged by a mismatch between its predictions and precision measurements of the anomalous magnetic moment of the muon, aμ. This disagreement was eventually reconciled, first through a determination in an ab initio lattice calculation1 of the most uncertain theoretical contribution, the leading-order hadronic vacuum polarization (LO-HVP), ({a}{\mu }^{\text{LO-HVP}}), and subsequently by experimental results2 and updates of the reference standard-model predictions using lattice results for ({a}{\mu }^{\text{LO-HVP}}) (ref. 3). Here we present a new calculation for this crucial quantity, obtaining ({a}_{\mu }^{\text{LO-HVP}}=715.1(2.5)(2.3)[3.4]\times 1{0}^{-10}). This reduces the uncertainty by a factor of 1.6 compared with our earlier computation1. We use a hybrid approach that includes a small, long-distance contribution from experiments in a low-energy regime in which they all agree. Our approach combines the strengths of experimental and lattice data in different energy ranges, achieving better precision than with either alone. Our lattice quantum chromodynamics (QCD) simulations are performed on finer lattices than in ref. 1, allowing for an even more accurate continuum extrapolation. Combined with the calculations of the other standard-model contributions summarized in ref. 3, our result leads to a prediction that differs from the recent measurement of aμ (ref. 4) by only 0.5 standard deviations. This provides a notable validation of the standard model to 11 digits.
Phenomenology, Theoretical particle physics
Structural basis of fungal β-1,3-glucan synthase inhibition by caspofungin
Original Paper | Cryoelectron microscopy | 2026-04-21 20:00 EDT
Zhenning Ren, Abhishek Chhetri, Chang Liu, ShuYu Offner, Kedar Sharma, Mario J. Borgnia, Wonpil Im, Kenichi Yokoyama, Seok-Yong Lee
Invasive fungal infections pose life-threatening risks to the increasing population of immunocompromised patients1,2. Treatment remains challenging due to limited antifungal drugs and increasing resistance. β-1,3-d-glucan synthase (GS), comprising the catalytic Fks1 and the regulatory small GTPase, Rho1 (refs. 3,4), is the target of clinically important echinocandin antifungals. Despite recent studies5,6,7, the mechanisms of GS catalysis, Rho1 regulation and echinocandin inhibition and resistance remain elusive. Here we present cryo-electron microscopy structures of native Saccharomyces cerevisiae Fks1 (ScFks1) solved under catalytically relevant conditions, revealing its interactions with the antifungal caspofungin (CFN), glucan product from the translocation channel and Rho1. CFN forms a ternary complex with nascent glucan and Fks1 at the membrane-protein interface, suggesting an unexpected role of CFN in stalling polymer translocation. Our echinocandin-resistant S643P structure suggests a resistance mechanism: the substitution destabilizes CFN and glucan binding through both allosteric structural perturbation and direct steric clash. Rho1 binding induces active site rearrangements essential for catalysis, including that of the ‘latch loop’ for donor substrate coordination. Furthermore, we identify YMR295C as an auxiliary subunit. These findings elucidate the mechanisms of GS-mediated glucan synthesis and its inhibition and resistance by echinocandins, laying the groundwork for rational antifungal design.
Cryoelectron microscopy, Fungal biology, Permeation and transport, Polysaccharides, Transferases
Quadruple pegRNA enables programmable and efficient large genomic insertion
Original Paper | CRISPR-Cas9 genome editing | 2026-04-21 20:00 EDT
Ya-jing Shi, Zi-yi Ding, Ying Wu, Zhou He, Yi-zhou Zhang, Yu-lu Zhang, Yu-ming Zhang, Xiang-rui Huang, Hao Yin, Ying Zhang
Precise, site-specific insertion of large gene sequences holds great promise for the treatment of diverse genetic disorders. Although prime editing using paired guide RNAs (pegRNAs) can mediate targeted integration, insertion efficiency drops sharply for payloads exceeding 300 base pairs1,2,3. Here we present a rationally designed quadruple pegRNA strategy (QuadPE) for efficient and programmable insertion of large DNA fragments. Through screening different designs, we identified that combinations of two genome-targeting pegRNAs in a PAM-out or PAM-in orientation, when paired with two donor-targeting pegRNAs in linear or circular form, yield optimal efficiency. Using QuadPE, we achieved stable integration efficiency of DNA fragments ranging from 1.6 to 26 kb, with efficiencies of around 40% at multiple loci with minimal off-target insertion activity. QuadPE substantially outperformed recombinase-mediated (PASSIGE and PASTE)4,5 and transposase-mediated (CAST)6 insertion systems, particularly for larger payloads, showing a 11-fold, 61-fold and 12-fold improvement for a 9.5 kb insertion, respectively. Notably, QuadPE was effective in both dividing and non-dividing primary cells such as human primary T cells and post-mitotic neurons, establishing QuadPE as a powerful and precise platform for large-fragment gene insertion without the need for double-stranded breaks or recombinases.
CRISPR-Cas9 genome editing, Genetic engineering
Ceramic-like strength and metallic toughness in a bulk metallic glass
Original Paper | Mechanical properties | 2026-04-21 20:00 EDT
Zhengqing Cai, Shidong Feng, Zhen-Qiang Song, Yanhui Liu, Bo Xu, Zijing Li, Yanhui Zhang, Yingdan Liu, Ruilin Zheng, Xinyu Zhang, Weihua Wang, Li-Min Wang, Ri-Ping Liu
Metals and ceramics have contrasting limitations–metals exhibit lower strength and poor high-temperature stability, whereas ceramics are inherently brittle. Materials combining high strength, fracture toughness and thermal stability remain an important scientific objective. Here we report Re-Co-Ta-B bulk metallic glasses (BMGs) that overcome this fundamental limitation, achieving a remarkable fracture strength of about 6.43 GPa while maintaining around 30 MPa m1/2 fracture toughness. This strength value exceeds previously reported values for BMGs and crystalline metals and approaches the strength of advanced ceramics while far exceeding them in toughness. These alloys exhibit pronounced resistance to thermal softening and harsh environments, retaining a strength of 4.4 GPa at 900 K with negligible oxidation and corrosion. Synchrotron measurements and aberration-corrected microscopy reveal the origin of these properties: a unique amorphous structure that inherits a high degree of crystal-like short-range order from the Re7B3 intermetallic phase. First-principles calculations indicate that this atomic framework is strengthened by directional Re-B covalent bonds embedded in a metallic matrix, thereby bridging the ceramic and metallic bonding. This work suggests structural heredity as a guiding principle for engineering next-generation amorphous materials with previously unattainable property combinations.
Mechanical properties, Metals and alloys
Nature Reviews Materials
Transport of polaritons in hyperbolic media
Review Paper | Nanophotonics and plasmonics | 2026-04-21 20:00 EDT
Hai Hu, Hanchao Teng, Na Chen, Zhuoxin Xue, Zhipei Sun, F. Javier García de Abajo, Qing Dai
Hyperbolic polaritons – hybrid light-matter quasiparticles emerging in extremely anisotropic media – have redefined the limits of nanoscale light manipulation. Their open isofrequency surfaces support high-momentum states and directional energy flow, enabling subdiffractional control that reaches the single-atom limit. Although initial progress was driven by artificial metamaterials, the discovery of natural hyperbolic materials spanning a dimensional hierarchy has shifted focus towards intrinsic, low-loss and highly tunable platforms. This Review establishes a transdimensional framework that unifies hyperbolic polaritons across 0D to 3D systems, encompassing shear, ghost and topological edge modes. We analyse the transition from descriptive exploration to a design-oriented paradigm, focusing on topological transitions and anomalous transport at interfaces for sophisticated wavefront engineering. Finally, we present an interdisciplinary framework for hyperbolic polaritons at the intersection of materials science, physics, chemistry and information technology, outlining the strategic path towards integrated polaritonic circuits and quantum-chemical control.
Nanophotonics and plasmonics, Polaritons
Physical Review Letters
Spectral Decomposition and High-Accuracy Green’s Functions: Overcoming the Nyquist-Shannon Limit via Complex-time Krylov Expansion
Article | Quantum Information, Science, and Technology | 2026-04-21 06:00 EDT
S. Paeckel
The accurate computation of low-energy spectra of strongly correlated quantum many-body systems, typically accessed via Green's functions, is a long-standing problem posing enormous challenges to numerical methods. When the spectral decomposition is obtained from Fourier transforming a time series, …
Phys. Rev. Lett. 136, 160401 (2026)
Quantum Information, Science, and Technology
Precision Measurement of $CP$ Violation and Branching Fractions in ${B}^{±}→{K}{S}^{0}{h}^{±}$ ($h=π$, $K$) Decays and Search for the Rare Decay ${B}{c}^{±}→{K}_{S}^{0}{K}^{±}$
Article | Particles and Fields | 2026-04-21 06:00 EDT
R. Aaij et al. (LHCb Collaboration)
The decay , with a asymmetry expected to be close to zero in the standard model, is theoretically clean and sensitive to potential new physics. An analysis of the decays and is performed using proton-proton collision data collected by the LHCb experiment at a center-of-m…
Phys. Rev. Lett. 136, 161801 (2026)
Particles and Fields
Precise $^{136}\mathrm{Xe}$ Double Beta Decay Measurement in PandaX-4T with Implications on the Nuclear Matrix Elements and Majorons
Article | Nuclear Physics | 2026-04-21 06:00 EDT
Zhe Yuan et al. (PandaX Collaboration)
The continuous spectrum of double beta decay () provides a sensitive probe to test the predictions of the standard model and to search for signatures of new physics beyond it. We present a comprehensive analysis of the spectrum utilizing of exposure from the PandaX-4…
Phys. Rev. Lett. 136, 162501 (2026)
Nuclear Physics
Subyield Dynamics in Yield-Stress Materials
Article | Physics of Fluids, Earth & Planetary Science, and Climate | 2026-04-21 06:00 EDT
Alice Woodbridge, Kasra Amini, Fredrik Lundell, Outi Tammisola, Anne Juel, Robert J. Poole, and Cláudio P. Fonte
The mechanical response of yield-stress materials below the yield point remains a subject of debate. Two of the most widely used constitutive models for these materials offer fundamentally conflicting views: one permits plastic flow at all stress levels, while the other assumes entirely recoverable …
Phys. Rev. Lett. 136, 164001 (2026)
Physics of Fluids, Earth & Planetary Science, and Climate
Racetrack Computing with a Topological Boundary Ratchet
Article | Condensed Matter and Materials | 2026-04-21 06:00 EDT
Parisa Omidvar, Markus Bestler, Sima Zahedi Fard, Oded Zilberberg, and Marc Serra-Garcia
Multistable order parameters provide a natural means of encoding nonvolatile information in spatial domains, a concept that forms the foundation of magnetic memory devices. However, this stability inherently conflicts with the need to move information around the device for processing and readout. Wh…
Phys. Rev. Lett. 136, 166601 (2026)
Condensed Matter and Materials
arXiv
Thermo-mechanically coupled phase-field fracture model considering elastocaloric effect of shape memory alloy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Shen Sun, Wei Tang, Weiwei He, Igor Polozov, Min Yi
Modelling fracture behavior of the shape memory alloy (SMA) that interacts with martensitic transformation and the associated elastocaloric effect (eCE) still remains challenging. Herein, a thermo-mechanically coupled phase-filed fracture model considering elastocaloric effect of SMA is proposed to simulate the cracking process coupled with the non-isothermal martensitic transformation and the associated eCE. In the phase-field model, both the thermal strain induced by eCE and the eigen strain induced by the phase transition are considered. An empirical degradation function is adopted to describe the thermal conductivity decreasing with the fracture order parameter. The model is validated with the finite element method and tensile fracture properties of Mn-Cu SMA are simulated. It is found that the martensite variant nucleates at the stress concentration where the crack initiates, and commonly spreads with an angle of 45 degree. The thermal expansion strain caused by the eCE could strengthen the critical load capacity. A large kinetic parameter for phase transition and the large orientation angle could enhance the strength and temperature change of eCE while the deformation capacity is reduced. The phase-field model demonstrates its ability in the thermal-mechanically coupled toughening of SMA. It also provides a possible fracture-resistance strategy by the utilization of eCE for elastocaloric devices.
Materials Science (cond-mat.mtrl-sci)
18 pages, 15 figures
Logarithmic Entanglement and Emergent Dipole Symmetry from a Strongly Coupled Light-Matter Quantum Circuit
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Hybrid systems where a quantum material strongly couples to a nonlocal cavity photon mode have emerged as a new frontier for controlling and probing quantum correlations, yet the structure and scaling of light-matter entanglement produced by the nonlocal coupling remains poorly understood. We address this problem through an exactly solvable framework based on reinterpreting the Power–Zienau–Woolley (PZW) transformation as a \textit{light-matter quantum circuit} that couples the photonic position quadrature $ X \sim a + a^\dagger$ to the many-body dipole $ \mathcal{P}$ of a one-dimensional quantum chain. We derive a closed-form expression for the reduced density matrix valid at all coupling strengths, in which off-diagonal elements between matter states of unequal dipole are suppressed by a Gaussian factor encoding the full weak-to-ultrastrong coupling crossover. At weak coupling, the reduced density matrix takes a Lindbladian form with $ \mathcal{P}$ as the jump operator, and the entanglement entropy is controlled by the dipole variance. At ultrastrong coupling, the density matrix becomes exactly block-diagonal in dipole sectors, reflecting an \textit{emergent dipole symmetry} dynamically imposed by the photon field, with entanglement entropy given exactly by the Shannon entropy of the dipole-sector weight distribution. Applying this framework to a half-filled Su–Schrieffer–Heeger chain, we show that, at strong coupling, both the light-matter entanglement and the spatial entanglement of the photon-dressed matter state scale logarithmically with system size, $ S_\infty \sim \frac{\alpha}{2}\log L$ , robust across the SSH phase diagram. The logarithm originates from the photon resolving a single collective coordinate $ \mathcal{P}$ whose fluctuations grow as $ L^{\alpha/2}$ , a distinct mechanism from the logarithmic entanglement of critical one-dimensional systems.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
13 pages, 8 figures
Hatsugai-Kohmoto-like Models for Altermagnets and Odd-Parity Magnets
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Konstantin Rickelt, Denis Sedov, Mathias S. Scheurer
We introduce a generalized Hatsugai-Kohmoto multi-orbital model and study its phase diagram and physical properties in the additional presence of perturbations that lift any extensive ground-state degeneracies. The unperturbed, exactly solvable model already displays a rich set of spectral functions, including regimes reminiscent of unconventional magnets. We map the first-order study of additional spatially local multi-orbital Hubbard interactions to a Heisenberg model in momentum space, which leads to symmetry-breaking instabilities already at weak coupling. Interestingly, translational-symmetry breaking orders, such as antiferromagnetism, are excluded. Instead, in addition to ferromagnetism, unconventional $ p$ -wave and $ d$ -wave magnets occur, characterized by spin order on the bonds of the underlying square lattice. Adding another type of momentum-space interaction, which still allows to solve the model exactly, is shown to stabilize a non-degenerate singlet ground state that retains the spin splitting characteristic of unconventional magnets. We discuss its impact on the spin structure factor. Taken together, our findings show that Hatsugai-Kohmoto-like models provide a rich playground for unconventional magnetism.
Strongly Correlated Electrons (cond-mat.str-el)
General Conditions for Axis Dependent Conduction Polarity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Poulomi Chakraborty, Brian Skinner, Penghao Zhu
Axis-Dependent Conduction Polarity (ADCP) refers to the phenomenon in which electrical transport within a single material is p-type along one crystallographic direction and n-type along the perpendicular direction. This behavior enables a variety of thermoelectric applications that do not require a heterojunction between two different materials. In this work, we investigate ADCP theoretically and derive a set of generic and quantitative criteria for identifying and predicting materials that exhibit ADCP. Specifically, by analyzing the thermopower for generic metals, semimetals, and semiconductors, we obtain transparent inequalities that are both necessary and sufficient for the emergence of ADCP. Moreover, we review known ADCP materials and verify that their band-structure characteristics and relaxation parameters are consistent with the inequalities derived here.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 4 figures
Localization and universality of three-dimensional pseudospin-$s$ fermions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Quantum interference of electrons in disordered conductors is a sensitive probe of the internal structure of quasiparticles, revealing universal signatures of symmetry through weak localization (WL) and weak antilocalization (WAL). While these phenomena are well understood for the conventional Schrödinger and Dirac-Weyl fermions, their fate in the broader class of multifold chiral fermions remains largely unexplored. We develop a unified framework for semiclassical transport and quantum interference in three-dimensional disordered fermions with an arbitrary pseudospin $ s$ . Starting from a general short-range matrix disorder $ \mathcal{M}$ , we derive compact expressions for elastic lifetimes and ladder vertex corrections for arbitrary pseudospin with multiband effects, and then show that in the scalar-disorder limit while the Drude conductivity is strongly pseudospin and helicity dependent, in contrast, the leading quantum interference correction exhibits a striking universality: its magnitude remains identical to that of conventional diffusive metals and Weyl fermions, while its sign is determined solely by the parity of $ 2s$ , placing half-integer pseudospins in the symplectic class (WAL) and integer pseudospins in the orthogonal class (WL). We also analyze the role of interband and intervalley scattering for $ s=3/2$ . By solving the resulting coupled Bethe-Salpeter equations, we demonstrate that channel mixing suppresses WAL and drives a crossover toward localization. Our results establish a general theory of localization across the full pseudospin hierarchy, revealing an interplay between internal geometry, symmetry class, and transport universality.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
10+37 pages, 4+1 figures
Exploring Entropic Orders: High Temperature Continuous Symmetry Breaking, Chiral Topological States and Local Commuting Projector Models
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Po-Shen Hsin, Ryohei Kobayashi
High temperature is usually expected to destroy order: as the Gibbs state approaches the infinite-temperature limit, it becomes an equal-weight ensemble over all states and the system is generically disordered. Recent works showed that entropic order can violate this expectation through coupling to bosons in classical lattice models and quantum field theories, where the ordered states have higher entropy. Here we present new analytic methods for constructing quantum lattice models that exhibit entropic orders. In particular, we construct quantum lattice models with continuous symmetry breaking at high temperature in 1+1 dimensions and clarify how entropic order can evade the Hohenberg-Mermin-Wagner theorems. We also construct high-temperature entropic $ p+ip$ chiral topological superconducting states in 2+1 dimensions with temperature-independent anyon correlation functions. In addition, we obtain a broad family of high-temperature entropic non-chiral topological orders. We show that the entropic topological orders have strong higher form symmetries at high temperature unlike the conventional topological orders, and the symmetry is spontaneously broken. These results follow from two general constructions that couple a given lattice model with a low-temperature ordered phase either to ordered bosons or, for local commuting-projector Hamiltonians, to more general bosonic degrees of freedom.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
12 pages
$P$-wave Orbital Magnetism
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Realization of unconventional odd-parity magnets usually requires noncollinear spin textures of the underlying lattice. We propose a different concept of $ p$ -wave magnetism that originates from an orbital texture induced by loop currents. The resulting $ p$ -wave orbital magnetism is protected by the combined translation and time-reversal symmetry, with even-parity components arising when the symmetry is broken. Our proposal is exemplified by a two-dimensional (2D) lattice model whose energy spectrum contains Dirac points and which is characterized by a nontrivial topology controlled by the magnitude of the loop currents. Since the odd-parity magnetism precludes macroscopic magnetization, we suggest measuring it via orbital Hall conductivity. Our work establishes orbital degrees of freedom as an additional platform for unconventional $ p$ -wave magnetism beyond noncollinear spin textures, as well as makes a step forward to bridging odd-parity magnetism and topology.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 7 figures
Conformal Data for the $O(2)$ Wilson-Fisher CFT in $(2+1)$-Dimensional Spacetime from Exact Diagonalization and Matrix Product States on the Fuzzy Sphere
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Arjun Dey, Loic Herviou, Christopher Mudry, Slava Rychkov, Andreas Martin Läuchli
We study at zero temperature a microscopic quantum spin-1 model on the fuzzy sphere that realizes the $ O(2)$ Wilson-Fisher conformal field theory (CFT) in $ (2+1)$ -dimensional spacetime at a quantum critical point. Here, we use the fuzzy-sphere regularization as it preserves the full spatial $ SO(3)$ rotational symmetry of the CFT, enabling the state-operator correspondence that maps energy eigenstates directly to CFT operators. Using exact diagonalization (ED) and matrix product state (MPS) techniques combined with conformal perturbation theory (CPT), we extract conformal data including scaling dimensions and operator product expansion (OPE) coefficients. We identify 32 primary operators and their descendants, organized by the conserved $ O(2)$ charge $ S^{z}$ and spatial angular momentum $ L$ . Our numerical results for the scaling dimensions of the lowest primary operators show good agreement with conformal bootstrap predictions. We verify predictions from the large charge expansion, which provides systematic predictions for operators carrying large $ U(1)$ charge, connecting the Goldstone mode physics in the ordered phase to phonon primaries at the critical point.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Lattice (hep-lat), High Energy Physics - Theory (hep-th)
Equation of state for the edge flow of chiral colloidal fluids
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-04-22 20:00 EDT
Jessica Metzger, Cory Hargus, Julien Tailleur, Frédéric van Wijland
We explore the edge flows that emerge at boundaries in nonequilibrium passive and active chiral colloidal fluids. We show that these complex interface currents obey an equation of state that relates their fluxes to bulk observables. For confined fluids, the edge flux is given by the average odd stress in the fluid. In phase-separated systems, the flux along the interface is given by the jump of the odd stress across the interface. We then use the equation of state to reveal, and contrast, the microscopic origins of the edge currents in passive and active systems.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
9 pages, 5 figures
Charge Transport Capacity as a Probe of Resonances in Models of Many-Body Localization
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-04-22 20:00 EDT
Jessica Kaijia Jiang, Federica Maria Surace, Olexei I. Motrunich
The fate of Many-Body Localization (MBL) in the thermodynamic limit remains elusive, partly because numerical studies suffer from unexplained finite-size effects. We introduce and numerically study the charge transport capacity (CTC) – a quantity that upper bounds the number of particles that can ever be transported across a central cut of a 1D lattice. For ergodic systems, the CTC is linear with the system size $ L$ , while we expect it to be $ O(1)$ for localized models. Surprisingly, in the interacting Anderson model for numerically accessible $ L$ , the disorder-averaged CTC is small, but grows with $ L$ at an increasing rate. Moreover, this growth rate appears to be independent of the disorder strength $ W$ at very large $ W$ . We find that, for these system sizes, this growth occurs because, as $ L$ increases, many-body resonances that transport more charge across the cut become more likely. Using a perturbative model for the weakly interacting regime, we provide an understanding of the microscopic origins of the growth of these charge transport resonances (CTRs). We find that the CTRs are sensitive to charge configurations over a spatial region whose size is set by the range of the resonance, not by $ W$ , and that numerics cannot access system sizes where their behavior will converge. However, this effective model is consistent with a regime of strong disorder where, for large $ L$ , resonances are exponentially suppressed in their size. Finally, we study measures of average charge transport and suggest that for strong enough disorder, average product states can only transfer $ O(1)$ charge. Our work suggests that the unsettled growth of short-ranged many-body resonances with $ L$ contributes to the numerical drift towards thermalization at numerically accessible system sizes, and provides an understanding of how they can remain controlled or eventually destabilize the MBL phase.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
51 pages, 25 figures
Large Scale Optimization of Disordered Hubbard Models through Tensor and Neural Networks
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Jacob R. Taylor, Sankar Das Sarma
We theoretically demonstrate a practical method for tuning randomly disordered 2D quantum-dot grids underlying spin qubit platforms using vision-based neural networks trained on tensor-network generated charge-stability data. We show that a simulatable local $ 3\times 3$ window already contains sufficient information to tune the central dot within a much larger array, thereby validating a sliding-window approach in which one tunes a local region and then translates that window across the lattice to calibrate a larger device. This avoids the computationally intractable necessity for obtaining the ground states for large systems with exponentially large Hilbert space. For the experimentally relevant case where only the on-site disorder is unknown, the neural network predicts the relevant parameters with very high fidelity in the $ 3\times 3$ setting [$ R^2 >0.99$ ], and after fine tuning on only a small number of larger-device samples, it retains high accuracy for the central dot of a $ 5\times 5$ plaquette [$ R^2\approx 0.98$ ]. When all the dots parameters are treated as unknown, prediction of the on-site disorder remains robust [$ R^2>0.9$ for both $ 3\times 3$ and $ 5\times 5$ ], although the remaining parameters are substantially more difficult to infer from the same charge-stability data. This shows that the most practically important disorder parameter for tuning can still be inferred reliably even in the fully disordered setting for the computationally difficult 5x5 arrays.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 Page, 4 Figures
Proximitized Topological Insulator Charge Island Fabricated via In Situ Multi-Angle Stencil Lithography
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Benedikt Frohn, Tobias Schmitt, Vanessa Serrano, Anne Schmidt, Michael Schleenvoigt, Albert Hertel, Benjamin Bennemann, Abdur Rehman Jalil, Detlev Grützmacher, Peter Schüffelgen
Hybrid superconductor-topological insulator (TI) nanostructures constitute a promising materials platform for exploring proximity-induced superconductivity in systems with topologically protected surface states. A key obstacle has been the realization of clean and well-controlled superconductor-TI interfaces, as TI surfaces rapidly degrade under ambient conditions. Here, we introduce a fully in situ, multi-angle stencil lithography technique that enables the fabrication of proximitized charge islands in TIs. The approach combines selective-area growth of (Bi,Sb)$ _2$ Te$ _3$ nanoribbons with angle-controlled deposition of diffusion barriers, superconducting Al, and ultrathin oxide tunnel barriers, allowing scalable fabrication of hybrid nanostructures without post-growth processing. Low-temperature transport measurements reveal robust Coulomb blockade and a pronounced suppression of low-energy conductance which vanishes with magnetic field, consistent with proximity-induced superconductivity in the island. These results establish a versatile nanofabrication platform that enables access to previously unexplored TI-based hybrid quantum devices and opens new routes for investigating superconductivity in topological nanostructures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
6 pages, 4 figures (supplement: 1 page, 2 figures)
Competition and coexistence of superconductivity and nematic order in a two-dimensional electron gas with quadrupolar interactions
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Nei Lopes, Guilherme da Silva do Vale, Daniel G. Barci
We investigate the interplay between superconductivity and nematic order in a two-dimensional electron gas with competing pairing and quadrupolar forward-scattering interactions. The model includes both $ s$ -wave and $ d$ -wave superconducting channels. We compute the mean-field free energy density and determine the phase diagrams as functions of interaction strengths and temperature by solving a set of coupled self-consistent equations. At zero-temperature, we find that the nematic order competes strongly with $ d$ -wave superconductivity, leading to a direct first-order phase transition, while its interplay with $ s$ -wave pairing allows for a coexistence phase characterized by an anisotropic Fermi surface with a uniform superconducting gap. At finite-temperatures, quadrupolar interactions promote the emergence of additional superconducting components, giving rise to regimes where $ s$ -wave, $ d$ -wave, and nematic orders coexist. Our results highlight the role of symmetry and interaction strength in shaping the phase structure and provide a minimal framework to describe intertwined nematic and superconducting phases in correlated electron systems.
Superconductivity (cond-mat.supr-con)
8 pages, 5 figures
Dynamical magnetism in the disordered cubic lattice material $γ$-${\rm Ba}{3}{\rm CoNb}{2}{\rm O}_{9}$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Fanjun Xu, Ralf Feyerherm, Cecilie Glittum, Thomas J. Hicken, Hubertus Luetkens, Jonas A. Krieger, Cintli Aguilar-Maldonado, Sven Luther, Lucy K. Saunders, Clemens Ritter, Peter Fouquet, Margarita Russina, Karel Prokes, A.T.M. Nazmul Islam, Bella Lake
$ \gamma$ -$ {\rm Ba}{3}{\rm CoNb}{2}{\rm O}_{9}$ realizes a disordered simple-cubic spin-$ 1/2$ lattice in which Co$ ^{2+}$ ions randomly occupy one third of the sites, placing the system close to the site-percolation threshold for magnetic order. Specific-heat, susceptibility, neutron spin-echo, and muon spin-rotation measurements reveal a broad thermodynamic crossover, short-range magnetic correlations, and persistent fast spin dynamics down to at least 0.1~K, with no evidence for static order or conventional spin-glass freezing. Monte Carlo simulations yield a broad distribution of orphan spins, finite clusters, and an infinite network. The calculated orphan-spin fraction ($ \approx 8.8%$ ) agrees well with the weakly correlated spin fraction inferred from magnetization ($ \approx 8.2%$ ). Exact diagonalization of a diluted $ S = 1/2$ Heisenberg model captures the broad magnetic specific-heat anomaly and supports the coexistence of weakly and strongly correlated spin environments. These results support a picture in which spin-$ 1/2$ quantum fluctuations, together with dilution and proximity to the percolation threshold, can support a disorder-driven dynamical state with short-range correlations in three dimensions, distinct from both classical spin glasses and geometrically frustrated quantum spin liquids.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
17 pages, 15 figures
Tunable turbulence in driven microscale emulsions
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-04-22 20:00 EDT
Majid Bahraminasr, Anand Yethiraj
We present a tunable, non-equilibrium oil-in-oil emulsion that serves as a model system for investigating the transition from controlled droplet deformation to multiscale flows reminiscent of turbulence. By utilizing a miscible mixture of silicone and motor oils as the continuous phase and the immiscible castor oil as the droplet phase, we isolate electrical conductivity as a single experimental control parameter, varying it by over two orders of magnitude while keeping viscosity and permittivity nearly constant. This high degree of control allows us to systematically traverse the electrohydrodynamic (EHD) phase diagram with dielectric constant and conductivity as control parameters. We validate small-deformation theory at low fields before driving the system into a regime of multiscale, unsteady flows at high fields. We employ three complementary approaches on the same system (particle image velocimetry (PIV), used to map velocity fields, and rheometry and differential dynamic microscopy (DDM), two techniques used to probe viscosity and diffusion) to quantify the emergence of scale invariance in the energy spectra with increasing field strength. Above a threshold field, we find that the spatio-temporal energy spectra obtained by PIV analysis of droplet dynamics display power-law scaling, $ E(k) \sim k^{-\alpha_k}$ , where $ \alpha_k$ approaches the inertial turbulence exponent of $ 5/3$ at high fields. Energy spectra from rheometry also yield a power law, $ S(\nu) \sim \nu^{-\alpha_\nu}$ , with $ \alpha_\nu = 5/3$ at high fields. Mean square displacement (MSD) analyses on the same datasets reveal super-diffusive behavior, $ \mathrm{MSD} \sim t^{\gamma}$ , with $ \gamma = 3/2$ . These observations provide strong evidence of a conductivity-tunable transition to EHD-driven turbulence in a microscale emulsion.
Soft Condensed Matter (cond-mat.soft)
Stripping Symmetry: Electrochemical Oxidation to a Superconducting Polar Metal in Au2Pb0.914P2
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Scott B. Lee, Stephanie R. Dulovic, Joseph W. Stiles, Xin Zhang, Fatmagül Katmer, Sudipta Chatterjee, Jaime Moya, Allana G. Iwanicki, Abby N. Neill, Chris Lygouras, Tieyan Chang, Tyrel M. McQueen, Yu-Sheng Chen, Leslie M. Schoop
Polar metals and noncentrosymmetric superconductors are exceptionally rare, yet their broken inversion symmetry can give rise to emergent electronic phenomena including mixed singlet-triplet superconducting pairing. As only a few such materials have been found among known compounds, accessing new examples requires synthetic strategies that go beyond conventional crystal growth. Here, we use electrochemical topotactic deintercalation to remove Pb from the centrosymmetric parent compound Au$ _2$ PbP$ _2$ , producing the polar metal Au$ _2$ Pb$ _{0.914}$ P$ _2$ . Unlike conventional chemical doping, this transformation actively drives structural symmetry-breaking: the partial removal of Pb triggers a cooperative electronic and geometric rearrangement, mediated by a second-order Jahn-Teller effect and stereochemically active lone pairs, that locks the product into a polar, noncentrosymmetric superspace group Ama2(01g)ss0. We solve the complete (3+1)D modulated structure by synchrotron single-crystal X-ray diffraction and confirm the polar assignment through nonlinear electronic transport. Below T$ _c$ = 1.52 K, Au$ _2$ Pb$ _{0.914}$ P$ _2$ becomes a type-II superconductor whose heat capacity and AC susceptibility both exhibit power-law behavior, suggestive of a gap structure governed by the broken inversion symmetry of the host lattice. This work establishes electrochemical oxidation as a rational route to metastable noncentrosymmetric superconductors through chemically directed symmetry-breaking.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
105 pages, 5 main figures, 41 supplemental figures, 19 supplemental tables
Landau levels and magneto-optics in 30$^\circ$ quasi-periodic twisted bilayer graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Masaru Hitomi, Takuto Kawakami, Mikito Koshino
We develop a theoretical framework for Landau levels in quasi-periodic twisted bilayer graphene at a $ 30^\circ$ twist angle, a system without translational symmetry but possessing 12-fold rotational symmetry. Using a quasi-band formalism, we incorporate the magnetic field through a conventional momentum substitution in the zero-field Hamiltonian. This approach provides a transparent physical interpretation by directly relating the Landau levels to the quasi-band structure, allowing them to be understood as quantized orbits of quasi-band pockets. By using this method, we reveal distinctive spectral features, including nearly flat bands with weak magnetic-field dependence and highly degenerate levels arising from twelve off-center pockets. The resulting Landau levels are classified by two quantum numbers: the Landau-level index and the angular momentum associated with the underlying quasicrystalline symmetry. We also compute the magneto-optical conductivity and show that optical transitions follow angular-momentum selection rules enforced by the 12-fold symmetry. Our approach provides a symmetry-based and computationally efficient framework for bulk quantum magneto-optics in quasicrystalline van der Waals systems, predicting spectroscopic signatures accessible in high-field infrared and THz experiments.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 6 figures
Stabilization of bulk quantum orders in finite Rydberg atom arrays
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-04-22 20:00 EDT
Yash M. Lokare, Matthew J. Coley-O’Rourke
Arrays of ultracold neutral atoms, also known as Rydberg atom arrays, are rapidly developing into a powerful and versatile platform for quantum simulation. However, theoretical predictions about the bulk quantum phases of matter present in these systems have often diverged from experimental realizations on finite-sized arrays due to the strong effects of the boundaries. Here we propose a general, experimentally straightforward strategy to mitigate the effects of the boundaries and thus enable finite-sized arrays to stabilize bulk-like quantum order. Our scheme makes use of the properties of the ubiquitous disordered phase in Rydberg systems, driving the boundaries into an unbiased set of configurations that depend on the bulk physics. We numerically demonstrate the efficacy of this protocol in one- and two-dimensional systems on both ordered and critical phases.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Quantum Physics (quant-ph)
main text: 5 pages, 4 figures. supplementary material: 8 pages, 4 figures
Energy landscape of the kagome antiferromagnet: Characterization of multiple energy scales
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-04-22 20:00 EDT
Brandon B. Le, Seung-Hun Lee, Gia-Wei Chern
We investigate the energy landscape of the kagome Heisenberg antiferromagnet within its coplanar ground-state manifold. Although coplanar states are degenerate at harmonic order, transitions between them require collective weathervane-loop rotations whose barriers grow strongly with loop size. To characterize this structure, we construct disconnectivity graphs using two complementary approaches: exact enumeration and minimax-barrier calculations for small lattices, and a statistical construction for large lattices based on random walks through configuration space, with loop length used as a proxy for barrier height. The exact landscape reveals a dominant low-barrier scale associated with elementary six-spin loops and a broader higher-barrier sector from longer rearrangements. For large systems, the statistical analysis exposes a hierarchy of barrier scales, including a pronounced six-spin-loop peak and an intermediate scale-free regime of loop lengths. This hierarchy provides a natural basis for multiple dynamical time scales: six-spin loops govern the fastest local relaxation, while slower collective dynamics arise from activation of longer loops. These results show that the coplanar manifold is dynamically rugged, with its low-energy dynamics governed by a hierarchy of loop-mediated barriers.
Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 4 figures
Coordination-number dependent universality in Mixed Wet Percolation
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-04-22 20:00 EDT
Jnana Ranjan Das, Santanu Sinha, Alex Hansen, Sitangshu Bikas Santra
Mixed-wet percolation was introduced recently in the context of two-phase flow in porous media. In this model, the sites of the primal lattice are occupied with a certain probability $ p$ , and bonds are placed on the dual lattice between two adjacent occupied and unoccupied sites of the primal lattice. The occupied bonds on the dual lattice form perimeter clusters. In this paper, we investigate the scaling properties of the geometric quantities associated with the perimeter clusters of mixed-wet percolation on the dual triangular and dual honeycomb lattices. Although mixed-wet percolation on the dual triangular lattice with a higher coordination number ($ z=6$ ) exhibits ordinary site percolation, the model on the dual honeycomb lattice with a lower coordination number ($ z=3$ ) exhibits the properties of the hull of ordinary site percolation clusters. Such a $ z$ dependent breakdown of universality in mixed-wet percolation is rare in the percolation literature. The perimeter clusters in the triangular lattice represent the boundary of the site clusters in the primal lattice, whereas the perimeters in the honeycomb lattice represent their hulls. Because of the low $ z$ of the honeycomb lattice, the external and internal perimeters remain isolated. However, the combined external and internal perimeters form cluster boundaries of the site clusters that belong to the site percolation universality class.
Statistical Mechanics (cond-mat.stat-mech)
Proximity Magnetism in Mn(Bi,Sb)2Te4-(Bi,Sb)2Te3/MnTe Natural Heterostructures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Owen A. Vail, Shu-Wei Wang, Yasen Hou, Dinura Hettiarachchi, Jean-Felix Milette, Tim B. Eldred, Wenpei Gao, Wendy Sarney, Haile Ambaye, Jong Keum, Valeria Lauter, George J. de Coster, Matthew J. Gilbert, Don Heiman, Jagadeesh S. Moodera, Hang Chi
Magnetic topological insulators and their heterostructures provide great opportunities in coupling band topology with nontrivial spin configuration for enhanced spintronic device performance as well as designing totally new magnetoelectric systems and functionalities. We find that Mn interdiffusion from MnTe when interfaced with (Bi,Sb)2Te3 stabilizes as self-organized Mn(Bi,Sb)2Te4 septuple lamellae amongst alternating (Bi,Sb)2Te3 quintuple layers, as observed using scanning transmission electron microscopy and depth-sensitive polarized neutron reflectometry. We further demonstrate a valuable combination of magnetic and topological orders in these naturally formed Mn(Bi,Sb)2Te4-(Bi,Sb)2Te3 heterostructures that are exchange coupled with MnTe. Magnetotransport experiments and quantum magnetism simulations reveal that, above its own Neel temperature TN of 20 K, Mn(Bi,Sb)2Te4 mediates the exchange field leading to an anomalous Hall effect at the (Bi,Sb)2Te3/MnTe interface, with an enhanced interfacial TN exceeding 200 K. This novel magnetic interface in turn allows a robust and deterministic spin-orbit torque switching without an external magnetic field at a low critical current density of 300 kA cm-2. The antiferromagnetically coupled architecture of Mn(Bi,Sb)2Te4-(Bi,Sb)2Te3/MnTe, featuring unique magnetic and topological proximity effects across a chalcogenide backbone, is rich in fundamental interface physics and holds potential for practical applications in spintronics.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Magnetic Polarons Enable Exceptional Magnetocaloric Response
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Joshua Ancheta, Caeli Benyacko, Fanghao Zhang, Stephen D. Wilson, Bolin Liao
Magnetocaloric materials are typically limited by a trade-off between magnetic entropy and field responsiveness. Here we show that magnetic polarons provide an intermediate regime that mitigates this constraint and enables an exceptional magnetocaloric response. Using EuB$ _6$ as a model system, we combine thermodynamic and magnetic measurements to demonstrate that nanoscale ferromagnetic clusters emerging near the Curie temperature strongly enhance the field-induced entropy collapse. These clusters possess large effective moments that respond efficiently to applied fields while retaining substantial entropy due to their small size and dynamic fluctuations. As a result, EuB$ _6$ exhibits a giant cryogenic magnetocaloric response, with both large isothermal entropy change and adiabatic temperature change in the technologically important 10-40 K range. Our results identify magnetic polarons as an underexplored route for optimizing magnetocaloric performance and establish an intermediate magnetic length scale as a design principle for high-performance cryogenic cooling materials.
Materials Science (cond-mat.mtrl-sci)
AngstromPro: A versatile software for massive N-dimensional STM data management, visualization and in-depth analysis
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Huiyu Zhao, Jiahao Yan, Catherine Dawson, Haitao Yang, Hong-Jun Gao
We present AngstromPro, a versatile, modular and open-source software built on Python for managing, visualizing and analyzing large datasets acquired via Scanning Tunneling Microscopes (STM). Its robust architecture features a top-level module that manages a Global Variables List and a sub-modules List. Each sub-module, equipped with its own Local Variables List to maintain a tidy workspace, can be tailored for specific tasks, including built-in modules like the Multiple 2D Images Visualizer and Analyzer. These modules support step-by-step data processing and extensibility for custom algorithms and functions. AngstromPro’s design supports a wide range of users, from those relying on built-in tools to developers creating custom algorithms or extending the platform with new modules. In its implementation, AngstromPro separates graphical user interface components from data processing algorithms, a strategy that enhances code readability, maintainability, and extensibility. The embedded algorithms reflect commonly adopted and recently developed approaches in STM data analysis, including background subtraction, perfect lattice correction, Lawler-Fujita correction, and sub-atomic precision registration, along with additional standard data processing routines. By consolidating fragmented STM workflows, maintaining detailed processing histories, and providing a flexible platform for customization, AngstromPro enhances both the efficiency, reliability, and reproducibility of STM data analysis, while enabling the rapid development of new methods and modules.
Superconductivity (cond-mat.supr-con)
The source code for this project is open source and available on Github at this https URL AngstromPro
Room-temperature multistage metastability in a moiré superstructure
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
B. Q. Lv, Yifan Su, Alfred Zong, Karna Morey, Bryan T. Fichera, Qiaomei Liu, Dong Wu, Yongchang Ma, Dupeng Zhang, Faran Zhou, Makoto Hashimoto, Dong-Hui Lu, Donald A. Walko, Haidan Wen, Jiarui Li, Suchismita Sarker, Jacob P. C. Ruff, N. L. Wang, Nuh Gedik
Metastability is fundamental not only to phase ordering and transitions, but also to a broad range of modern technologies, from memory devices to metallic glasses. In condensed-matter physics, charge density waves (CDWs) offer versatile platforms for accessing metastable states due to their sensitivity to external stimuli. However, most metastable CDW states are stabilized only at low temperatures, limiting their practical utility. In this study, we report the observation of electrically driven, room-temperature, nonvolatile metastable states in the bulk form of EuTe$ _4$ , a recently discovered compound that hosts an innate moiré superlattice characterized by the stacking of incommensurate monolayer and bilayer CDWs. Systematic transport measurements reveal discrete resistivity plateaus and strong electric-field sensitivity, with a large number of metastable states readily induced across a wide temperature window within a giant hysteresis loop, making them well-suited for high-temperature, multi-bit memory applications. By integrating photoemission spectroscopy, diffraction, and in-situ transport measurements, we uncover that these metastable states do not stem from conventional mechanisms such as the emergence of new ordered phases or changes in incommensurate periodicity. Instead, they are characterized by a suppression of the original CDW amplitude and a reduction in correlation length, pointing to a unique electric-field-induced switching of out-of-plane CDW phases in the moiré superstructure. Our findings not only provide critical insights into metastable phenomena in moiré systems with stacked electronic orders but also establish EuTe$ _4$ as a promising platform for developing room-temperature, multi-bit memory devices.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
11 pages, 4 figures
Geometric quantification for nonlinear deformation in knitted fabrics
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-04-22 20:00 EDT
Jiani Fang, Xiaoxiao Ding, Gary P. T. Choi
Knitted fabrics exemplify a broad class of architected materials capable of large deformations, enabling shape morphing, mechanical biocompatibility, and embedded multifunctionality without material damage. Although geometric nonlinearity has been intuitively utilized in their design, a quantitative description of stitch-resolved deformation and its temporal evolution remains lacking. Here, we introduce a geometric quantification framework that reconstructs smooth yarn centerlines and fabric surfaces from sparse yarn-level representations and extracts interpretable descriptors across dimensions. Applied to representative knitted structures, this framework resolves how global deformation is distributed among stitch reorientation, loop bending, surface bending, and dilation. Moreover, it reveals how regions of large geometric variation emerge, persist, and redistribute over time. Rather than directly measuring stress, these geometric descriptors define a unified geometric state space for comparing knitted structures and identifying candidate regions of mechanical localization. The framework provides a quantitative language for nonlinear deformation in knits and establishes a geometry-based representation that can be coupled to constitutive models, experimental measurements, and graph-based inverse-design workflows.
Soft Condensed Matter (cond-mat.soft), Numerical Analysis (math.NA)
Energy relaxation due to two-phonon scattering of electrons: Breakdown of the energy diffusion model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Joshua Covey, Dmitrii L. Maslov
Recent THz spectroscopy of the quantum paraelectric SrTiO$ _3$ (arXiv:2501.15771) and a high-$ T_c$ cuprate (arXiv:2503.15646) has renewed interest in energy relaxation in correlated electron systems. We consider a situation in which single-phonon scattering is forbidden by symmetry or momentum conservation, while two-phonon scattering is allowed. Solving the Boltzmann equation, we show that above the Bloch-Grüneisen temperature the energy relaxation rate from two soft transverse optical phonons exceeds the single-phonon one: while the latter scales as $ 1/T$ , the former is linear in $ T$ . This dominance of two-phonon scattering invalidates the usual picture of energy diffusion due to frequent scattering by subthermal phonons; instead, energy relaxes via rare scattering events involving thermal phonons. Below the Bloch-Grüneisen temperature, the energy relaxation rate scales as the single-particle rate, namely as $ T^3$ for soft phonons. For anisotropic electron bands, an intermediate regime appears between two Bloch-Grüneisen temperatures, in which both allowed single-phonon and two-phonon processes scale as $ T^2$ .
Strongly Correlated Electrons (cond-mat.str-el)
5 pages, 3 figures, supplementary material
Stealthy hyperuniform disorder: A new route to controlling electric states and magnetic phase transition in correlated systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Akihisa Koga, Takanori Sugimoto
We investigate the effects of stealthy hyperuniform bond distributions on the electronic and magnetic properties of the Hubbard model on the honeycomb lattice. Hyperuniform structures, distinct from random and quasiperiodic ones, have recently attracted considerable interest due to their anomalous suppression of density fluctuations. By diagonalizing the noninteracting Hamiltonian, we show that a linear density of states (DOS) robustly emerges, while the stealth property of the bond distribution changes the wave functions in the higher-energy region extended and significantly modifies the DOS near the band edge. To clarify the impact on magnetism, we apply the real-space Hartree approximation to the Hubbard model. We find that, the phase transition always occurs between semimetallic and antiferromagnetically ordered states and its critical interaction strength is sensitive to the stealth property. A comparison with the quasiperiodic honeycomb tiling further highlights the role of structural correlations. These results demonstrate that stealthy hyperuniform disorder provides a novel route to controlling electronic states and magnetic phase transitions in correlated systems.
Strongly Correlated Electrons (cond-mat.str-el), Disordered Systems and Neural Networks (cond-mat.dis-nn)
9 pages, 11 figures
Seniority Eigenstate Configuration Interaction
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Thomas M Henderson, Guo P. Chen, Gustavo E. Scuseria
Zero-seniority methods have shown great promise for the description of strongly-correlated electronic systems. Other seniority sectors have been much less explored, and in particular the maximal seniority sector and zero seniority have the same underlying algebraic structure. We introduce a seniority eigenstate configuration interaction in which the wave function is constrained to have good fixed local seniority for each paired orbital, by which we mean we partition orbitals into a pairing set with seniority zero, and a spin set with seniority one. We show how to build the effective Hamiltonian for this ansatz, and demonstrate that high-seniority wave functions have unexpectedly excellent accuracy for strongly-correlated fermionic systems, with accuracy competitive with or better than seniority zero for the Hubbard model and for the dissociation of the nitrogen molecule.
Strongly Correlated Electrons (cond-mat.str-el)
Submitted to J. Chem. Phys
Re-examination of electronic structure of dilute Kondo transition-metal ions substituted into a Heavy Fermion compound
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Kou Takubo, Shintaro Suzuki, Kohei Yamamoto, Kohei Yamagami, Masafumi Horio, Toshiaki Ina, Kiyohumi Nitta, Masaichiro Mizumaki, Eiji Ikenaga, Yosuke Matsumoto, Hiroki Wadati, Satoru Nakatsuji
Correlations between the localized and conductive spins/charges have been the central issue of various fascinating quantum phenomena found on itinerant electron systems. Here, the obvious multiplet structures are presented on the Mn 2$ p$ to 3$ d$ x-ray absorption for a heavy fermion $ \alpha$ -(Yb,Lu)(Al$ _{1-x}$ Mn$ _x$ )B$ _4$ , indicating that the unoccupied electronic structure of the Mn site is described as the correlated high-spin 2+, even though magnetic measurements show the Mn sites to be nonmagnetic. This apparently paradoxical result demonstrates that a ligand field can effectively appear between localized Mn 3$ d$ and surrounding B 2$ p$ orbitals, which has been anticipated as a manifestation of a Kondo effect but not been clearly confirmed for most itinerant metals in spectroscopy. By contrast, the Mn 2$ p$ photoemission indicates that the occupied Mn$ ^{2+}$ 3$ d$ electrons still exhibit itinerant and nonlocally screened nature also owing to the Kondo-like correlation with the conductive B 2$ p$ , and heavier Yb 4$ f$ and 5$ d$ bands below the Fermi energy. The asymmetry on the particle-hole stimulates a reconsideration of the correlation and screening effects in the core-level spectroscopies.
Strongly Correlated Electrons (cond-mat.str-el)
23 pages .8 figures
Ultrafast Light-Induced Magnetoelectric Effect in van der Waals Magnetic Semiconductor Heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Wenyi Zhou, Ravi Kumar Bandapelli, Hari Paudyal, Bangzheng Han, I-Hsuan Kao, Ziling Li, Yuqing Zhu, Durga Paudyal, Jyoti Katoch, Simranjeet Singh, Roland K. Kawakami
Atomic-scale heterostructures of van der Waals (vdW) magnets and semiconductors provide a unique environment for exploring magnetic dynamics. In contrast to typical photothermal excitation of precessional magnetization dynamics by a pump laser pulse, we find that ultrafast optical excitation of a WS$ _2$ /CrGeTe$ _3$ (CGT) bilayer produces an opposite sign of magnetic torque compared to an isolated CGT film. Experimental observations by time-resolved magneto-optic Kerr effect (TR-MOKE) and theoretical analysis by density functional theory (DFT) and Landau-Lifshitz-Gilbert (LLG) simulations support a mechanism in which charge transfer of photoexcited carriers across the interface alters the perpendicular magnetic anisotropy, which in turn generates a torque on the magnetic layer to trigger precessional magnetization dynamics. These results provide new avenues for ultrafast manipulation of magnetization in vdW heterostructures with type-II band alignments. Lastly, we show that optically-generated spin currents from WS$ _2$ into CGT can also trigger precessional dynamics via angular momentum transfer.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
8 pages, 4 figures
Discovery of Graphene Sheets and C-Rich Micro-Oval structure in Stingless Bee Hive; Leading to an Emergent Material with Debut of Blue Emission
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Manas Kumar Dalai, Ankita Mahakhuda, Abinash Prusty
Naturally produced stingless bee hive (NP-SBH) is an intricately produced material by the combination of waxes, resin and other biological materials that offers protection and structural stability to the bee colony. This study explores a detailed analysis of Indian stingless bee hive material using multi-characterization techniques approach to evaluate their morphological, ultrastructural, chemical composition and their crystallinity. FESEM reveal uniformly distributed micro-oval structures along with graphene sheets throughout the observed region. Furthermore, Energy Dispersive X-ray Analysis (EDAX) provides the richness of carbon (C) in graphene as well as in the micro-oval structure. HRTEM gives an insight about the internal ultrastructure and arrangement of atoms in the sample which revealed the presence of multiple graphene sheets. The ring shape electron diffraction pattern and high resolution lattice fringes provide the arrangement of carbon atoms, with interlayer spacing (d) value 3.4 Å, well agreed with that of graphene. Furthermore, X-ray Diffraction (XRD) and Fourier Transform Infrared (FTIR) spectroscopy support the presence of graphene. As a debut, we observe blue emission from PL spectroscopy with decay times 1.18 ns (42 %) and 5.41 ns (58 %).
Materials Science (cond-mat.mtrl-sci), Biological Physics (physics.bio-ph)
Controlling Quantum Materials by Growth: Thermodynamics, Kinetics, and Defect Engineering in Transition Metal Dichalcogenides
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Anzar Ali, Md Ezaz Hasan Khan, Mahmoud Abdel-Hafiez
Transition metal dichalcogenides exhibit a wide range of semiconducting, metallic, correlated, and topological electronic states that arise from strong coupling between lattice structure, dimensionality, and electronic degrees of freedom. In these materials, crystal growth is not merely a preparative step but a thermodynamic boundary condition that establishes chemical potentials, defect populations, polytype stability, and access to metastable phases. As a result, synthesis determines the structural and defect landscape from which collective electronic behavior emerges.
In this Review, we develop a unified thermodynamic and kinetic framework that connects growth conditions to phase stability, defect energetics, and microstructure. We examine how chemical potential constraints define stability windows, how supersaturation and mass-transport regimes govern nucleation and morphology, and how nonequilibrium pathways enable kinetic trapping and polymorph selection. Bulk and thin-film synthesis approaches, including chemical vapor transport, flux growth, physical vapor transport, solvent-assisted crystallization, chemical vapor deposition, and molecular beam epitaxy, are placed within a common thermodynamic and kinetic map to clarify how distinct growth regimes produce characteristic disorder profiles and structural phases.
By explicitly linking synthesis variables to charge-density-wave order, superconductivity, band topology, and correlation effects, this Review establishes crystal growth as a central parameter in determining the effective electronic Hamiltonian realized in experiment. This perspective provides a physically grounded framework for improving reproducibility and guiding deterministic control of emergent quantum phases in layered materials.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
20 pages, 7 figures
Triple-${\bf Q}$ collinear state with compensated ferrimagnetic nature on frustrated kagome lattice
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Kazushi Aoyama, Hikaru Kawamura
Spin-selective band splitting without net magnetization and spin-orbit couplings serves for a next-generation spin-current generator, and its typical platforms are altermagnets and compensated ferrimagnets as well, where the existence of a crystal asymmetry or nonequivalent sites is essential. Here, we theoretically demonstrate that such a splitting can be realized in a triple-{\bf Q} 12-sublattice state emerging in a $ J_3$ -dominant kagome antiferromagnet, without the help of the crystal asymmetry. Reflecting the multi-sublattice nature, a local magnetization reveals a fully compensated ferrimagnetic pattern in units of a triangle plaquette, leading to $ s$ -wave-type spin splittings in magnon and electron bands. This enables an atiferromagnetic spin Seebeck effect at zero field in insulating systems and filling-controlled polarized states in metallic systems, highlighting the potential of frustrated magnets to realize novel spintronics functionalities.
Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 4 figures, accepted for publication in npj Spintronics
Spin-orbit-induced quantum chiral phases
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Daesik Kim, Hyojae Jeon, Seongjun Park, Seungho Lee, Jung Hoon Han, Hyun-Yong Lee
The scalar spin chirality (SSC), whose nonzero value $ \langle {\bf S}_i \cdot ({\bf S}_j \times {\bf S}_k) \rangle \neq 0$ implies the breaking of time-reversal and certain point-group symmetries in the ground state, is a key quantity characterizing chiral magnetism in both classical and quantum settings. The classical SSC is manifested, for instance, in skyrmion crystal phase, while the quantum SSC is still highly sought after in various frustrated spin-1/2 models. An interesting possibility that has not been explored so far is the case in which SSC is symmetry-wise allowed, yet remains zero classically due to the collinear or coplanar arrangement of spins, but is generated by virtue of quantum fluctuation. We demonstrate the existence of precisely such a phase in a spin-1/2 triangular-lattice model with XXZ interaction, spin-orbit-induced exchange interactions, and an external magnetic field. Using iDMRG, we thoroughly map out the phase diagram of the model and identify several phases with coexisting magnetic order and SSC. The nonzero SSC arises despite the classical magnetic order being collinear or coplanar. We provide detailed magnon analysis to ascribe its origin to quantum fluctuations around classical magnetic order. The estimate of SSC from magnon analysis agrees with iDMRG results quantitatively. We map out the magnon spectrum and its Berry curvature, culminating in the prediction of finite thermal Hall conductivity in these phases with SSC.
Strongly Correlated Electrons (cond-mat.str-el)
18 pages, 8 figures
Coherent Microwave Driving of Domain Wall Depinning in a Ferrimagnetic Garnet
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Hanchen Wang, Laura van Schie, Adam Erickson, Lauren J. Riddiford, Davit Petrosyan, Christian L. Degen, Richard Schlitz, William Legrand, Pietro Gambardella
Coherent control of domain wall dynamics offers a route to fast manipulation of magnetic textures beyond thermally activated motion. We demonstrate resonant excitation of linear and nonlinear dynamics of a pinned domain wall in a ferrimagnetic garnet thin film driven by a microwave field. Using scanning nitrogen-vacancy magnetometry and nonlocal spin-pumping measurements, we identify a low-frequency mode inside the magnon gap, originating from the localized oscillatory motion of a domain wall across a pinning line defined by a Pt stripline. Upon increasing the microwave drive into the nonlinear regime, this mode enables domain wall depinning at reduced external magnetic fields. Micromagnetic simulations reveal a progression from localized oscillations to partial relocation between pinning sites and, ultimately, complete escape from the pinning region with increasing driving power. These results establish resonant excitation of domain walls at engineered pinning sites as a mechanism for manipulating magnetic textures via localized nonlinear dynamics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Optical conductivity of topological semimetal Nb$_{2n+1}$Si$n$Te${4n+2}$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
We study the linear optical conductivity of the Nb$ _{2n+1}$ Si$ _n$ Te$ _{4n+2}$ family of layered van der Waals materials, which has recently gained considerable attention owing to its dimensionality-tunable electronic structure with a quasi-one-dimensional nodal-line state. At zero temperature, we analytically show that the Drude weight exhibits strong anisotropy: along the nodal-line direction it is finite at charge neutrality, whereas in the transverse direction it vanishes quadratically with Fermi energy. On the other hand, the interband optical conductivity exhibits the same linear frequency dependence along both the longitudinal and transverse directions, with only a direction-dependent slope in the low-frequency regime. We further analyze the leading finite-temperature corrections to the intraband and interband optical conductivities, showing that the zero-temperature results remain valid up to experimentally relevant temperatures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
When heat goes astray – non-local heating in a semiconductor
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Mahmoud Elhajhasan, Elena Trukhan, Katharina Dudde, Guillaume Würsch, Jana Lierath, Ian Rousseau, Raphaël Butté, Nicolas Grandjean, Nakib Haider Protik, Giuseppe Romano, Gordon Callsen
Heating of semiconductor devices limits their performance and lifetime, which must be addressed by thermal management starting at the heat source. It is a common assumption that the heat source and the resulting heat spot locally coincide, if their size exceeds the mean free paths of the main heat carriers, the phonons. We show that this paradigm of heat locality breaks down on length scales spanning several micrometers. As a consequence, non-local heating occurs in contradiction to Fourier’s law. Therefore, we heat laterally structured semiconductor membranes that feature a rising number of interfaces with a well-focussed laser and map-out lattice temperatures by Raman thermometry. Remarkably, the non-local heating can exceed the laser-induced local heating, which we attribute to ballistic phonon transport far above cryogenic temperatures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optics (physics.optics)
Pseudogap and Condensation in Cuprate Superconductors from NMR Shifts
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
The electronic properties of the high-temperature superconducting cuprates are encoded in complex sets of NMR data, but without microscopic theory, reliable NMR phenomenologies are in demand. Early analyses of NMR could only focus on very few materials and discovered spin singlet pairing and the enigmatic pseudogap. However, a coherent phenomenology of shift and relaxation could not be established, as incoming data from other cuprates complicated the picture. Today, due to work of many groups worldwide, planar copper and oxygen NMR data are available for most cuprates. Here, based only on symmetry of the two Cu hyperfine couplings, an anisotropic $ A_\alpha$ and isotropic $ B$ , the Cu shifts are disentangled, and two different shift components emerge. Upon doping the cuprates, metallic B-spins are created above the pseudogap temperature which is shared with metallic A-spins. Further doping decreases the pseudogap temperature and increases the B-spin, but less so the A-spin. The apparent linear rate of increase in density of states of the B-spin with doping increases nearly threefold above about $ x=0.20$ , where the pseudogap has disappeared and A and B turn into superconducting metals, i.e. they disappear rapidly at $ T_\mathrm{c}$ . The pseudogap temperature is a measure of the coupling between A and B, which suppresses the shifts but not nuclear relaxation. Spin singlet pairing involves A and B according to three simple rules for condensation which will be discussed. The optimal $ T_\mathrm{c}$ demands a special match between A and B and involves systems with a pseudogap. However, the highest $ T_\mathrm{c}$ of all cuprates is not encoded in the shift, but rather in nuclear relaxation and charge sharing between planar Cu and O. Relations to other probes are discussed.
Superconductivity (cond-mat.supr-con)
13 pages, 6 figures
Electronic-Entropy-Driven Crossover to Close-Packed Phases in Transition Metals under Strong Electronic Excitation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
S. Azadi, S.M. Vinko, A. Principi, T.D. Kuehne, M.S. Bahramy
Solid-solid phase transitions in metals are traditionally governed by changes in density or external pressure. Here, we show that electronic entropy alone can control structural stability and drive phase transitions at fixed density across transition metals. Using finite-temperature density functional theory, we construct pressure-temperature phase diagrams for 15 metals spanning hcp, fcc, and bcc-ground-state structures. Despite their diverse ground-state behavior, all systems exhibit a common high-temperature response: structural stability collapses toward a reduced manifold dominated by close-packed phases, with fcc emerging as the predominant structure, hcp persisting as a secondary phase, and bcc stability strongly suppressed. This identifies a robust entropy-driven crossover that progressively erases ground-state structural specificity under strong electronic excitation. To elucidate the microscopic origin of this behavior, we perform a detailed analysis of manganese, where spin-dependent calculations with a Hubbard U correction capture the interplay between magnetism, electronic localization, and lattice stability. At low temperatures, phase competition is governed by magnetic order and on-site Coulomb interactions, whereas increasing electronic temperature leads to demagnetization, phonon hardening, and the emergence of an entropy-dominated regime consistent with the universal trends. We show that electronic entropy generates a substantial hot-electron thermal pressure that modifies interatomic forces and drives structural rearrangements at fixed density, producing lattice-dynamical effects analogous to hydrostatic compression. These results establish electronic entropy as a fundamental thermodynamic control parameter for structural transformations in metals and provide a unified framework for understanding phase stability under extreme electronic excitation.
Materials Science (cond-mat.mtrl-sci), Plasma Physics (physics.plasm-ph)
Rippled graphene pores as fluidic memristive devices with synaptic and neuromorphic functionalities
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Wenzhe Zhou, Dongjiao Ge, Ao Zhang, Jincheng Xu, Yu Ji, Yiran Gong, Wenchang Zhang, Jidong Li, Li Lin, Zhiping Xu, Pengzhan Sun
Nanofluidic memristive devices work with nanoscale pores and ions dissolved in water, which harness the ionic memory effect aiming to store and process information. These devices share the same charge carriers as biological systems and bring hope for better emulating the neural functions and developing ionic circuits for neuromorphic applications. Specially, theory and experiments suggest that nanoconfinement is essential for inducing a memory effect, which places limit on the pore size to nm-scale or smaller. Such devices are difficult to scale up with precision and operate with long-term stability. Here, we show that a micrometer size pore, generally expected to exhibit a linear ion transport, can display a pronounced memory effect, if its rim is wrapped by strongly curved and tightly stacked graphene. We attribute the observation to slow ion dynamics confined in the rippled graphene edges. The devices are easy to scale up and integrate into fluidic circuits. The memory effect is ion-selective and exhibits long endurance comparable to the lifetime of synaptic proteins, which enables reversible modification of the conductance states using programmable voltage spikes and various electrolytes over a long time, akin to biological synaptic plasticity. Thanks to this plasticity, our devices and their integrated circuits enable storing, transmitting and processing information with high reliability, fidelity and accuracy, as evidenced in the identification of both greyscale and color images, and in the real-time analysis of emulated neural signals. Our results highlight nanoscale morphology of the pore wall as an important parameter regulating ion transport and indicate that the stringent nanoconfinement for ionic memory can be lifted from restricting the pore size to designing its rim structure. The devices and their integrated circuits may find use in ionic neuromorphic applications.
Materials Science (cond-mat.mtrl-sci)
Emergence of rigid Polycrystals from atomistic Systems with general Interactions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
We investigate the formation of polycrystalline structures in a class of particle systems. The atomistic energy is modeled as a sum of particle energies that favor atoms being locally isometric to a reference lattice. The discrete frame invariant energy allows for particle configurations in which no underlying lattice is assumed a priori.
We prove a discrete-to-continuum limit for configurations with finite surface-energy scaling by means of $ \Gamma$ -convergence. The resulting continuum theory is described by piecewise constant fields encoding the local orientation of the configuration. The limiting energy is concentrated on grain boundaries, corresponding to the interfaces between regions where the microscopic configuration has constant orientation. The associated energy density depends on the orientations of the two grains as well as on the normal to the interface.
Due to our assumptions on the rigid interactions, solid-solid phase transitions with interpolating boundary layers are not energetically favorable; the energy density therefore decomposes into twice the energy density for solid-vacuum transitions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Mathematical Physics (math-ph)
Spectral Signatures of Third-Order Pseudo-Transitions in Finite Systems: An Eigen-Microstate Approach
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-04-22 20:00 EDT
Wei Liu, Songzhi Lv, Xin Zhang, Fangfang Wang, Kai Qi, Zengru Di
Third-order pseudo-transitions in finite systems reflect reorganization beyond conventional criticality, yet their identification usually relies on microcanonical entropy, which is often inaccessible in practice. Here we introduce a spectral generalized response within the eigen-microstate framework. From the distribution of normalized spectral weights, we construct the third-order ratio $ R_3=K_3/(K_2)^3$ , which probes asymmetric redistribution among fluctuation modes beyond leading-mode condensation. Across Ising and Potts models on regular lattices and random regular networks, extrema of $ R_3$ consistently track higher-order anomalies. Combined with spectral projection, the method further distinguishes dependent and independent branches: the former remain tied to the dominant ordering channel, whereas the latter arise from redistribution within the subleading fluctuation subspace. The effective spectral dimension $ R_{\mathrm{eff}}$ provides the participation background in which these anomalies develop. These results establish a geometric characterization of third-order pseudo-transitions as reorganizations of statistical weight in configuration space and provide an order-parameter-free route to finite-size structural criticality.
Statistical Mechanics (cond-mat.stat-mech)
13 pages, 9 figures
Self-propulsion protocols for swift non-equilibrium state transitions and enhanced cooling in active systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-04-22 20:00 EDT
Kristian Stølevik Olsen, Hartmut Löwen
A control framework is proposed for inducing non-equilibrium state transitions in confined active matter, where the statistics of self-propulsion serve as the only control parameter. Positivity of the noise amplitudes and fundamental bounds on position-propulsion correlations define the admissible control space and impose speed-limits on transitions between non-equilibrium states. We show that non-stationary initial states facilitate additional speed-ups, corresponding to pre-loading the state with negative correlations. This enables active cooling protocols that outperform their passive counterparts.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
Daydreaming algorithm for Biased Patterns
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-04-22 20:00 EDT
Mikiya Doi, Masayuki Ohzeki, Federico Ricci-Tersenghi
The \emph{Daydreaming} algorithm was proposed as a learning rule that simultaneously reinforces stored patterns and suppresses spurious attractors to improve the storage capacity of the Hopfield model. Its effectiveness has been reported for both uncorrelated and correlated data. However, the existing formulation has mainly assumed unbiased patterns, and the formulation for biased patterns has not yet been sufficiently established. Biased patterns are known to be much more problematic for models of associative memories. In this study, we reformulate Daydreaming for biased patterns by starting from the underlying rationale of the pseudo-inverse rule. Specifically, we introduce the retrieval dynamics and an energy function based on the centered representation, and we derive a corresponding update rule for centered Daydreaming. We compare the centered pseudo-inverse rule with centered Daydreaming for biased patterns and examine the retrieval maps and eigenvalue distributions of the coupling matrices. Our results confirm that centered Daydreaming yields a larger basin of attraction than the centered pseudo-inverse rule. Moreover, as in previous studies, although both approaches aim to stabilize the stored patterns as fixed points, our results suggest that they shape the energy landscape through different mechanisms.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
10 pages, 4 figures
Unveiling the Superconducting Ground State of Heusler alloy Pd2ZrIn via muon spin relaxation and rotation measurement
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Kavita Yadav, Anoop M Divakaran, Jumpei G. Nakamura, Tsunehiro Takeuchi, K. Mukherjee
Full Heusler alloys XInPd2 (X= Zr, Hf and Ti) have recently attracted significant attention owing to their symmetry-driven electronic structure and also due to the interplay between disorder and emergent ground states. Within this family, Pd2ZrIn serves as a unique platform to study the effect of disorder on superconducting pairing. This alloy crystallizes in a cubic L21 structure with significant B2-type antisite disorder. Electrical resistivity and magnetic susceptibility studies confirm bulk type-II superconductivity with a transition temperature TC ~ 2.2 K. Zero-field {\mu}SR results reveal no evidence of spontaneous internal magnetic fields below TC, confirming the preservation of time-reversal symmetry. Transverse-field {\mu}SR spectra show the formation of a vortex lattice, consistent with type-II superconductivity, and the superfluid density is well described by a fully gapped, nodeless s-wave state with superconducting gap {\Delta} (0) ~ 0.33 \pm 0.01 meV. Furthermore, the estimated ratio of transition temperature and Fermi temperature (TC/TF) indicates that this alloy lies within the conventional superconducting regime on the Uemura plot. These results establish Pd2ZrIn as a weakly coupled, dirty-limit, type-II superconductor; with a fully gapped, nodeless order parameter and preserved time-reversal symmetry.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
Quantum transport in gapped graphene under strain and laser–electrostatic barriers
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Hasna Chnafa, Clarence Cortes, David Laroze, Ahmed Jellal
Electron transport in graphene under a laser-modulated barrier is studied in the presence of an energy gap, a scalar potential, and a uniaxial zigzag strain. The transfer-matrix approach is used with the boundary conditions to derive the transmission probabilities as functions of different system parameters. Without strain, raising either the energy gap or the potential generally reduces transmission in the central and lower sidebands. Moderate zigzag strain generates pronounced Fano-type oscillations that vanish at large strain, while transmission increases for low potential and decreases for high values. In the upper sideband, the incidence energy shifts the resonance peaks to the right, and growing the barrier width generates characteristic oscillatory patterns. Furthermore, increasing the laser field amplitude enhances transmission, whereas higher laser frequencies tend to suppress it. These findings offer new perspectives on controlling electronic transport in gapped graphene via external fields, strain, and potential applications in optoelectronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
12 pages, 10 figures. To appear in Physica B (2026)
Perspective: Quantum Computing on Magnetic Racetrack
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Ji Zou, Jelena Klinovaja, Daniel Loss
Magnetic domain walls have long been pursued as carriers of classical information for storage and processing. With the ability to create, control, and probe domain walls at the nanoscale, they are recently recognized as an ideal platform for studying macroscopic quantum effects and provide a natural blueprint for building scalable quantum computing architectures. In particular, the experimentally demonstrated high mobility of domain walls makes them not only suitable as stationary qubits but also as flying qubits, which may offer advantages over currently explored quantum computing platforms. In this Perspective, we outline our current understanding of the essential ingredients and key requirements for realizing universal quantum computation based on magnetic domain walls. We highlight promising concrete material platforms and identify the experiments that are still needed to advance this concept. We also discuss the potential challenges and point to new opportunities in this emerging research direction at the interface between magnetism and quantum information science.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
15 pages, 6 figures, invited Perspective
Intra- and Interlayer Excitonic Fine Structure of the Two-Dimensional Perovskite (PEA)$_2$PbI$_4$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Patrick Grenzer, Fabian Lie, Klaus H. Eckstein, Tobias Hertel, Linn Leppert
Two-dimensional halide perovskites host strongly bound excitons whose fine structure controls polarization selection rules and radiative recombination, yet several spectral features in (PEA)$ _2$ PbI$ _4$ remain controversially assigned. Here, polarization-resolved low-temperature photoluminescence combined with first-principles G$ _0$ W$ _0$ +BSE calculations resolves both the intralayer and interlayer excitonic fine structure of this prototypical n=1 Ruddlesden-Popper perovskite. The low-energy multiplet is consistently described as a purely excitonic intralayer fine structure governed by crystal symmetry, octahedral distortions, and the two-layer unit cell, without invoking Rashba or exciton-polaron mechanisms as the primary origin. A weaker doublet ~45 meV above the bright intralayer states is identified as interlayer excitons from its agreement with the calculated interlayer manifold in energy and splitting. Although the static calculations underestimate their oscillator strength and do not reproduce the observed orthogonal polarizations, distortion-induced mixing with bright intralayer excitons strongly enhances interlayer optical activity and provides a plausible explanation for their visibility. Our results establish interlayer excitons in (PEA)$ _2$ PbI$ _4$ and refine the excitonic description of fine structure in two-dimensional perovskites.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
10 pages, 5 figures. Submitted to Nano Letters
Four-layer charge density waves and chirality in CsV$_3$Sb$_5$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Fernando de Juan, Mark H. Fischer
The kagome superconductor CsV$ _3$ Sb$ _5$ is the only one in the AV$ _3$ Sb$ _5$ family (A=K,Rb,Cs) that shows a $ 2\times2\times4$ charge-density-wave (CDW) ground state competing with the more common $ 2\times2\times2$ . In addition, it is also the only one that shows second-harmonic transport and thus broken inversion symmetry, suggesting these two features are connected. In this work, we test whether the $ 2\times2\times4$ CDW can break inversion symmetry by analyzing its stacking energetics with a real-space Ginzburg-Landau free energy. In the limit where each layer is forced to adopt a fixed, threefold symmetric tri-hexagonal configuration, we find an analytical phase diagram mostly occupied by inversion preserving AB and ABCD stacked solutions. Relaxing this rigid layer constraint in a physically meaningful way consistent with \emph{ab initio}–calculated parameters, we find several new phases including an AABC solution and a distorted ABCD solution, which break inversion and all mirrors and are thus chiral. However, these phases occupy only small fractions of phase space, suggesting other mechanisms for inversion symmetry breaking may be at play in CsV$ _3$ Sb$ _5$ .
Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 5 figures
Electrically steered conduction topologies and period-doubling phase dynamics in VO2
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Siyuan Huang, Shuaishuai Sun, Yin Shi, Wentao Wang, Chunhui Zhu, Huanfang Tian, Huaixin Yang, Jun Li, Jianqi Li
The insulator-to-metal transition (IMT) in strongly correlated materials, such as vanadium dioxide (VO2), offers a transformative platform for next-generation adaptive electronics and neuromorphic computing. However, harnessing this non-equilibrium phase transition for deterministic device operation is fundamentally hindered by the inability to disentangle electric-field effects from Joule heating, owing to a lack of operando techniques capable of resolving phase dynamics at nanoscale spatial and sub-nanosecond temporal scales. Here, using a newly developed electrical-pulse-pump ultrafast transmission electron microscope (E-UTEM), we directly visualize the multi-scale electro-thermo-mechanical dynamics of the IMT in suspended VO2 devices. Our results reveal that electric-field-induced Poole-Frenkel (PF) emission, localized by patterned oxygen vacancies, plays a decisive role in redistributing the internal electric field to trigger a deterministic Mott transition. The extreme non-linearity of this PF effect enables the formation of dynamically reconfigurable connectivity topologies that bypass conventional thermal limits. Furthermore, we observe that the coupling of thermal and elastic energies governs a discrete domain evolution, characterized by step-wise and period-doubling configurational resets, which is a hallmark of non-equilibrium phase dynamics in constrained geometries. By integrating experimental imaging with phase-field simulations, we establish a comprehensive framework for the electrically-driven IMT and predict sub-100-ps switching kinetics. These findings provide a fundamental basis for the rational design of ultrafast, low-energy functional devices through nanoscale defect and strain engineering in correlated systems.
Materials Science (cond-mat.mtrl-sci)
39 page 4 figures
Superconducting properties of the three-dimensional Hofstadter-Hubbard model below the critical flux for Weyl points
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Pierpaolo Fontana, Luca Lepori, Andrea Trombettoni
The three-dimensional Hofstadter model exhibits a critical rational flux at which Weyl points emerge in the single-particle spectrum. We study the superconducting regime of the model in the presence of a Hubbard attractive interaction by tuning the magnetic flux across its critical value. We determine the phase diagram in the plane of the coprime pairs parametrizing the magnetic flux. We show that the system exhibits two distinct regimes separated by a critical flux $ \Phi_c$ : for $ \Phi>\Phi_c$ , a semimetal-to-superconductor quantum phase transition occurs at a finite interaction strength ($ U_c\neq0$ ), while for $ \Phi<\Phi_c$ superconductivity arises for arbitrarily weak attraction, with a BCS-like exponential scaling of the gap due to the finiteness of the density of states. Close to the transition, we study the scaling behavior and identify the critical exponents. Our results highlight the interplay between magnetic band topology and attractive pairing in three-dimensional Hofstadter systems.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
9 pages + 8 pages appendix/references, 11 figures
True random number generation through stochastic magnonic bistability
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Mengying Guo, Zhenyu Zhou, Denys Slobodianiuk, Roman Verba, Kristýna Davídková, Xueyu Guo, Xudong Jing, Yueqi Wang, Björn Heinz, Yiheng Rao, Carsten Dubs, Caihua Wan, Xiufeng Han, Andrii V. Chumak, Philipp Pirro, Qi Wang
True random number generators (TRNGs) underpin modern cryptography, yet existing implementations face fundamental trade-offs between speed, scalability, and entropy quality. Here, we demonstrate that stochastic switching in the bistable regime of spin-wave dynamics provides a physical entropy source for high-quality random number generation. Our magnonic random number generator (mRNG), based on a lithography-patterned microstrip on yttrium iron garnet (YIG), exploits thermal fluctuations near the nonlinear bistable regime to generate random bitstreams that pass all 15 NIST SP 800-22 statistical tests at rates with 20 Mb/s. We implement a random-bit multiplier using synchronized mRNG units and demonstrate scalability to 200-nm-wide nanoscale waveguides, establishing spin-wave bistability as a viable physical entropy source for integrated random number generation.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
13 pages, 4 figures
Field-induced antiferromagnetic transition in CeIrIn$_5$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Y. Tokunaga, M.-T. Suzuki, S. Krämer, H. Sakai, S. Kambe, H. Harima, D. Aoki, M. Horvatić, I. Sheikin
We report low-temperature $ ^{115}$ In nuclear magnetic resonance (NMR) study of the prototypical heavy-fermion compound CeIrIn$ _5$ in high magnetic fields applied close to the crystallographic $ c$ axis. For this orientation, a field-induced transition was previously reported to take place at about 28 T. Although we do not observe any change of the NMR spectrum above the transition, the intensity of the NMR lines drastically decreases as a consequence of a considerable shortening of the $ T_2$ relaxation time. In addition, $ 1/T_1$ shows a pronounced maximum at the transition. Taking into account previous high-field de Haas-van Alphen results in conjunction with band-structure calculations, our NMR results are most naturally explained by the field-induced transition into an antiferromagnetic state with the propagation vector $ \mathbf{Q} = (1/2, 1/2, 0)$ and magnetic moments aligned antiferromagnetically along the $ c$ axis. This makes CeIrIn$ _5$ a unique case where the application of the magnetic field induces an ordered state with moments antiferromagnetically aligned along the field direction.
Strongly Correlated Electrons (cond-mat.str-el)
Accepted for publication as a Letter in Phys. Rev B
Multimodal Transformer for Sample-Aware Prediction of Metal-Organic Framework Properties
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Seunghee Han, Jaewoong Lee, Jihan Kim
Metal-organic frameworks (MOFs) are a major target of machine-learning-based property prediction, yet most models assume that a single framework representation maps to a single property value. This assumption becomes problematic for experimental MOFs, where samples reported as the same framework can exhibit different properties because of differences in crystallinity, phase purity, defects, and other sample-dependent factors. Here we introduce Experimental X-ray Diffraction Integrated Transformer (EXIT), a multimodal transformer for sample-aware prediction of MOF properties that combines MOFid with X-ray diffraction (XRD). In EXIT, MOFid encodes MOF identity, whereas XRD provides complementary information about the experimentally realized sample state. EXIT is pre-trained on one million hypothetical MOFs with simulated XRD to learn transferable representations, leading to improved downstream performance relative to existing approaches. EXIT is fine-tuned on literature-derived experimental datasets for surface area and pore volume prediction. Incorporating experimental XRD improves predictive performance relative to models without experimental XRD, and attention analysis and sample-level case studies further show that EXIT assigns different predictions to samples sharing the same MOF identity when their XRD patterns differ. These results establish a practical step from framework-aware to sample-aware MOF property prediction and highlight the value of incorporating experimental characterization into porous materials informatics.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI)
22 pages, 7 figures
Josephson diode effect in multichannel Rashba nanowires: role of inter-subband coupling
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Ardamon Sten, Sudeep Kumar Ghosh
The Josephson diode effect (JDE) has attracted considerable attention for its ability to enable directional, dissipationless supercurrents in quantum devices. While hybrid semiconductor-superconductor nanowire Josephson junctions provide a canonical platform, most theoretical treatments assume the single-channel limit of the nanowire; however, realistic devices are inherently multichannel due to transverse confinement. Here, we investigate the JDE in multichannel Rashba nanowire Josephson junctions, focusing on the role of inter-subband coupling. We show that subband hybridization qualitatively modifies both the topological phase diagram and the JDE response of the device. In contrast to the single-channel case, the topological phase is restricted to a finite window of Zeeman fields, within which Majorana bound states lead to a strong enhancement of the diode efficiency. Crucially, inter-subband coupling enables a finite JDE even when the Zeeman field is aligned purely along the spin-orbit direction– a mechanism absent in independent-channel and strictly one-dimensional systems. Furthermore, multichannel coupling enhances spectral asymmetry and significantly increases the diode efficiency compared to single-channel junctions. These results identify multichannel hybridization as a key ingredient for realizing and optimizing nonreciprocal superconducting transport in experimentally relevant hybrid semiconductor nanowire Josephson junctions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
15 pages with 16 figures. Comments are welcome!
Hydrodynamics of the viscous electron fluid in cadmium
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
Xiaodong Guo, Xiaokang Li, Benoît Fauqué, Alaska Subedi, Lingxiao Zhao, Zengwei Zhu, Kamran Behnia
Thanks to electron-electron ($ e$ -$ e$ ) collisions conserving momentum, metallic electron fluids are viscous. Yet, this viscosity is rarely detectable in bulk transport. Here, we report on the canonical realization of the Gurzhi effect in an elemental three-dimensional metal: cadmium. Using focused ion beam microstructuring to tune the effective thickness, we detected a low-temperature size-dependent resistivity upturn in a finite window sandwiched between ballistic and diffusive regimes. Within this window, the electrical conductivity displays a simultaneous quadratic dependence on both sample size and temperature – fingerprint of a hydrodynamic flow. This leads us to quantify the amplitude and the temperature dependence of kinematic and dynamic viscosity of the electron fluid. In cadmium, in contrast with graphene and $ ^3$ He, the rate of momentum-conserving $ e$ -$ e$ collisions is not set by the main Fermi energy, but by Lilliputian energy scales and inter-valley bottlenecks.
Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 4 fiugres, with supplemental materials
Towards Application of Nanodiamonds for in-situ Monitoring of Radicals in Liquid Phase Chemical Reactions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Emma Herbst, Sebastian Westrich, Alena Erlenbach, Jonas Gutsche, Maria Wächtler, Elke Neu
In many chemical reactions, short-lived radical intermediates play a crucial role, while detecting such short-lived species in-situ remains challenging. The optically readable electronic spin of nitrogen-vacancy (NV) centers in diamond is a nanoscale sensor for such radical species: its longitudinal spin relaxation time (T$ _{1}$ ) reacts to magnetic fluctuations from the unpaired electrons of radical species in its local environment. In this setting, we demonstrate the successful in-situ detection of the nitroxide radical 2,2,6,6-Tetramethylpiperidinyloxyl (TEMPO) using NV center-based T$ _1$ relaxometry after depositing nanodiamonds onto the inner wall of a glass cuvette. A significant concentration-dependent shortening of the relaxation time was observed, from $ 197:\mu s \pm 21:\mu s$ without radical to $ 66:\mu s \pm 30:\mu s$ at a concentration of 1 M TEMPO. The detection is sensitive in the nanomolar (nM) range and the determined signal-to-noise ratio is between 1.6 and 3.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Chemical Physics (physics.chem-ph), Quantum Physics (quant-ph)
Competing Constraints on Superconductivity in Thick FeSe films
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Ya-Xun He, Xing-Jian Liu, Qun Wang, Ting Chen, Hassan Ali, Jia-Ying Zhang, Bao-Juan Kang, Zheng Zhang, Jun-Yi Ge
Superconducting films emerge from the complex interplay of multiple growth parameters, making their optimization challenging. In iron-based superconductors, compressive strain is known to enhance the transition temperature (Tc) of FeSe films, yet reported Tc values vary widely even on identical substrates, indicating factors beyond strain are critical. Here, we develop a high-throughput off-center pulsed laser deposition strategy that transforms plume inhomogeneity into combinatorial FeSe film libraries with continuous gradients in lattice parameter, composition, and disorder. We discover that the maximum Tc does not coincide with the plume center but can shift off-center, revealing a competition between favorable c-axis expansion, stoichiometry, and defect scattering. Systematic characterization of 80 thick films (>50 nm), combined with interpretable machine learning, shows that besides the strong correlate of c-axis lattice parameter to Tc, the stoichiometry and disorder scattering impose critical constraints on the achievable transition temperature, defining a narrow optimization window rather than a simple monotonic relationship. This framework yields Tconset=17.1 K in thick FeSe films and establishes a general framework combining combinatorial synthesis with machine learning to uncover constrained optimization landscapes in complex functional materials.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
Photonic Chirality for Braiding and Readout of Non-Abelian Anyons
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
We propose a cavity-based scheme that uses photonic chirality to control braiding and read out non-Abelian anyons in a fractional quantum Hall platform. Counter-propagating cavity modes interfere with a classical reference tone to create a rotating pinning landscape whose direction is set by photon circulation, so that opposite photonic branches drive opposite anyon loops. This realizes a branch-conditioned braid operation and maps the resulting braid response onto cavity intermode coherence. We derive the rotating pinning term and the readout relation at the effective-theory level, identify an operating window set by subgap driving, adiabatic transport, localization, and cavity coherence, and provide phenomenological diagnostics of transport locking. In the minimal four-anyon Ising realization, the leading signal reduces to a calibrated phase; more generally, the same readout structure becomes state dependent when the relative braid operator is non-scalar. The scheme provides a cavity route to braid-sensitive readout of non-Abelian anyons without relying on fragile electronic interference fringes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optics (physics.optics), Quantum Physics (quant-ph)
21 pages 1 fig 1 table
Spatially-resolved voltage-reversal due to Bernoulli potentials in dissipative Bi$_2$Sr$_2$CaCu$2$O${8+x}$
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Sharadh Jois, Gregory M. Stephen, Samuel W. LaGasse, Genda Gu, Aubrey T. Hanbicki, Adam L. Friedman
We measure magneto-transport and critical currents in Bi$ _2$ Sr$ _2$ CaCu$ _2$ O$ _{8+x}$ Hall bar devices. Above critical current in an applied magnetic field, we observe longitudinal differential voltage along one edge comparable in magnitude but opposite in sign to the other edge. This phenomenon is unaffected by reversal of the applied field, and seems unique to devices with invasive voltage contacts. We attribute the source of this behavior to particle-hole symmetry breaking in moving vortices and the formation of opposite Bernoulli potentials due to opposing vortex velocities at the edges where the invasive contacts create hotspots for rapid vortex nucleation and flux flow. These results are fundamental to the composition and flow of dissipative currents in layered superconductors.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Non-extensive entropy of Vinen quantum turbulence
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-04-22 20:00 EDT
In Ref. [1] the statistical structure of the turbulent cascade in the context of non-additive entropy was considered. Here we suggest that the vortex line ensemble in the Vinen quantum turbulence in superfluids is described by the non-extensive Tsallis-Cirto statistics with $ \delta=3$ .
Statistical Mechanics (cond-mat.stat-mech), General Relativity and Quantum Cosmology (gr-qc)
4 pages, no figures
Termination-Controlled Fractionalization and Hybridization at Topological Interfaces in Organic Spin Chains
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-04-22 20:00 EDT
A single organic spin platform hosts both dimerized $ S=\tfrac{1}{2}$ and effective Haldane $ S=1$ sectors, linked by bond-texture inversion. At the junction, the fractional mode is controlled by termination parity: quenched by local fusion at one termination and released as an uncompensated spin-$ \tfrac{1}{2}$ -like degree of freedom at the parity-shifted one. Two such internal boundary modes of a finite embedded Haldane domain hybridize with an exponentially decaying splitting, establishing termination parity as a design principle for engineering and coupling fractional boundary modes.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
Operando Characterization of Volume Changes in Lithium-Ion Battery Electrodes during Cycling using Isotope Multilayers
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Erwin Hueger, Daniel Uxa, Lars Doerrer, Jochen Stahn, Harald Schmidt
This study reports on advancements in operando characterization of volume changes in lithium-ion battery (LIB) electrode materials during electrochemical cycling. Volume changes are crucial for LIB operation because they are related to the amount of stored energy as well as LIB integrity, performance, and safety. The study introduces a method based on isotope multilayers as active material to track the intrinsic modification of electrode volume in real time under operating conditions with operando neutron reflectometry. A natGe-73Ge multilayer film is used as a model system to measure the volume change of amorphous germanium electrodes during charging and discharging. Isotope modulation produces a Bragg peak in the neutron reflectivity pattern, sensitive only to the modification of volume within the active material of the electrode. Battery side reactions, such as the growth and reduction of the solid-electrolyte interphase is excluded. Using this method, the volume modification as a function of Li content x in LixGe can easily be derived from the scattering vector position of the Bragg peak without fitting numerous complex reflectivity patterns. The experiments show a reversible volume change of amorphous germanium of up to 250 percent for x = 3, which appears to be largely independent of current density, cycle number, and the thickness of the individual Ge layers. Also, there are tentative indications that the crystallization and re-amorphization of LixGe are not influencing the volume change.
Materials Science (cond-mat.mtrl-sci)
Observation of field-odd and field-free superconducting diode effects in $\mathrm{Mo}_2\mathrm{C}$ nanoflakes
New Submission | Superconductivity (cond-mat.supr-con) | 2026-04-22 20:00 EDT
Wei Gao, Kaixuan Fan, Menghan Li, Jinhao Cheng, Qing Zhang, Shuaishuai Ding, Wenping Hu, Fan Yang, Dechao Geng, Hechen Ren
The superconducting diode effect (SDE) enables nonreciprocal supercurrent flow, holding immense potential for ultra-low-power quantum electronics. Intrinsic SDE typically requires materials with inherent symmetry breakings. Here, we report the discovery of SDE in chemical vapor deposition-grown molybdenum carbide ($ \mathrm{Mo}_2\mathrm{C}$ ) nanoflakes, a material traditionally considered centrosymmetric. Strikingly, this system uniquely hosts both field-odd and field-free SDEs. Transport measurements reveal a field-odd SDE with tunable efficiency exceeding 40% at 4 K under a perpendicular in-plane magnetic field. In a separate sample, a robust field-free SDE persists under zero-field and field-coolings. Out-of-plane field sweeps confirm the intrinsic nature of these phenomena. We propose that domain-boundary supercurrents or charge density wave-like orders drive this unexpected combination of symmetry breakings. Our findings establish air-stable $ \mathrm{Mo}_2\mathrm{C}$ as an ideal platform for nonreciprocal superconducting electronics operating at liquid-helium temperatures, expanding the search for SDE into nominally centrosymmetric superconductors.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Nonequilibrium Kramers Turnover in a Kerr Parametric Oscillator
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Daniel K. J. Boneß, Gabriel Margiani, Wolfgang Belzig, Alexander Eichler, Oded Zilberberg
Activation processes govern noise-induced switching between long-lived states. In an equilibrium double well, the thermally activated switching rate exhibits a prefactor with a nonmonotonic dependence on environmental coupling, a foundational crossover known as Kramers turnover. Here, we demonstrate a Kramers turnover analogue in a Kerr parametric oscillator, a driven-dissipative nonlinear system featuring two stable phase states. First, we analytically establish turnover physics in this out-of-equilibrium setting. There, the strong physical correlation between the activation barrier and intrinsic damping fundamentally obscures the underlying turnover physics. To overcome this limitation, we rescale the rotating-frame dynamics and introduce a tunable effective friction controlled entirely by the parametric drive. This rescaling comes at the cost of a concurrent rescaling of the effective temperature. Exploiting this simultaneous scaling, we leverage the effective temperature to extract the turnover directly from temperature-dependent observations. Subsequently, measuring noise-induced phase slips in a micro-electromechanical device, we observe a distinct crossover in the prefactor’s temperature dependence. Our results unambiguously isolate the out-of-equilibrium turnover regime and highlight that the competition between dissipation and fluctuations profoundly shapes activation dynamics also beyond equilibrium.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Statistical Mechanics (cond-mat.stat-mech), Classical Physics (physics.class-ph)
Hydrodynamic capture and release of a microswimmer by a meniscus corner
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-04-22 20:00 EDT
Subhasish Guchhait, Harshita Tiwari, Sumesh P. Thampi, Ranabir Dey
Biological microswimmers alter their motility in complex corner geometries, facilitating their survival. However, the dynamical features of low-Reynolds-number swimming at corners remain undefined. Here, we use active droplet microswimmers near a confined meniscus in a microchannel as a model system to study how microswimmer-corner interactions determine swimming patterns. Combining experiments, theory and simulations, we show that pusher-type micrsowimmers are attracted towards a meniscus corner, followed by transient trapping and eventual escape. We demonstrate that hydrodynamic interactions with the wall-interface corner intimately dictate the attraction and trapping or escape of the microswimmer on the basis of its strength. We show that the swimming trajectory at the meniscus corner can be tuned depending on the type of the microswimmer, the corner geometry and the viscosity ratio for the liquid interface. Our study provides a simple way to manipulate microswimmers by exploiting their hydrodynamic interactions near corner geometries.
Soft Condensed Matter (cond-mat.soft)
Landauer-based study of transport in Chern insulator heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
We study charge transport through a trivial-topological-trivial junction described by the continuous Qi-Wu-Zhang model, which realizes a two-dimensional Chern-insulating phase. The central region is tuned into the topological regime, while the adjoining leads remain trivial, and an electrostatic barrier of tunable height and width is applied exclusively to the topological slab. By matching wave functions across the interfaces, we obtain the angle- and energy-resolved transmission probability and demonstrate the occurrence of Klein tunneling despite the presence of a bulk spectral gap. Within the continuum Dirac description, this perfect transmission originates from the inversion of the Dirac mass across the junction, which reflects the band inversion of the central layer relative to the trivial leads. In the Qi-Wu-Zhang model considered here, this mass inversion coincides with the transition between trivial and Chern-insulating phases and is accompanied by finite Berry curvature that governs the nonlinear transport response. The resulting transmission function is then incorporated into a Landauer-Büttiker framework to analyze both linear and nonlinear transport. Closed-form expressions for the linear and nonlinear conductances are derived at zero and finite temperatures. In addition, we investigate the role of dephasing, showing how partial loss of coherence suppresses Fabry-Pérot oscillations while leaving the overall transport trends intact. Finally, we map out the interplay between barrier height, slab thickness, and topological mass parameter, identifying optimal regimes that yield enhanced rectification in the nonlinear response.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Disordered Systems and Neural Networks (cond-mat.dis-nn)
Accepted for publication in Physical Review B
Monotile kirigami
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-04-22 20:00 EDT
Hugo Hiu Chak Cheng, Gary P. T. Choi
Kirigami, the art of paper cutting, has been widely used in the modern design of mechanical metamaterials. In recent years, many kirigami-based metamaterials have been designed based on different planar tiling patterns and applied to different science and engineering problems. However, it is natural to ask whether one can create deployable kirigami structures based on the simplest forms of tilings, namely the monotile patterns. In this work, we answer this question by proving the existence of periodic and aperiodic monotile kirigami structures via explicit constructions. In particular, we present a comprehensive collection of periodic monotile kirigami structures covering all 17 wallpaper groups and aperiodic monotile kirigami structures covering various quasicrystal patterns as well as polykite tilings. We further perform theoretical and computational analyses of monotile kirigami patterns in terms of their shape and size changes under deployment. Altogether, our work paves a new way for the design and analysis of a wider range of shape-morphing metamaterials.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Computational Geometry (cs.CG)
Supermoiré domain-resolved effective Hamiltonians and valley topology in helical multilayer graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-04-22 20:00 EDT
Kyungjin Shin, Nicolas Leconte, Jeil Jung, Hongki Min
Extending moiré graphene beyond twisted bilayers, helical trilayer graphene has shown topological bands and correlated states with reshaped moiré periodicity. Here we develop a theoretical framework for helical multilayer graphene to investigate its supermoiré relaxation and low-energy electronic structure. Using real-space lattice calculations, we find that relaxation reconstructs the system into locally periodic single-moiré domains, which provide the basis for a continuum description. Within each reconstructed domain, downfolding the first-shell model yields effective Hamiltonians near the Dirac points that reveal how the low-energy spectrum decomposes into folded Dirac sectors. We further evaluate the valley Chern numbers encoded in these effective Hamiltonians, obtaining domain-dependent and gate-tunable topological responses consistent with the lattice calculations. Our results establish a domain-resolved organizing principle for thicker helical graphene stacks, in which folded Dirac sectors partition the low-energy spectrum, while local stacking families determine the corresponding band character and topological response.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
17 pages, 10 figures, 1 table
Lattice thermal transport from phonon spectra beyond perturbation theory
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Zezhu Zeng, Michele Simoncelli, David E. Manolopoulos
We develop a molecular dynamics framework to compute the mode-resolved phonon spectral density from classical correlations of an annihilation-like phonon variable. For harmonic oscillators, classical molecular dynamics exactly reproduces the corresponding quantum Kubo-transformed correlator, providing the basis for extension to anharmonic systems. Using PbTe as a benchmark and Cs$ _3$ Bi$ _2$ I$ _6$ Cl$ _3$ as a strongly anharmonic test case, we show that the method captures both quasiparticle and non-Lorentzian spectra beyond perturbative quasiparticle theory, while yielding thermal conductivity in good agreement with experiment. This framework provides a direct route from classical molecular dynamics to quantum-mechanical Wigner heat transport in solids.
Materials Science (cond-mat.mtrl-sci)
Electronic structure and oxidation states in high-pressure synthesized isostructural CeCN$_5$ and TbCN$_5$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Amanda Ehn, Florian Trybel, Talha Bin Masood, Leonid V. Pourovskii, Igor A. Abrikosov
Understanding the behavior of 4$ f$ electrons in materials containing rare earth elements is one of the fundamental questions within condensed matter physics. In this work the electronic properties of isostructural CeCN$ _5$ and TbCN$ _5$ , both recently synthesized at extreme pressure, are investigated using Density Functional Theory (DFT) calculations. We include the on-site Coulomb repulsion between localized 4$ f$ states within the static DFT+U framework; the DFT+U results are cross-checked with DFT+dynamical mean-field theory (DMFT) calculations within the quasi-atomic (Hubbard-I) approximation. Despite CeCN$ _5$ and TbCN$ _5$ being isostructural compounds Ce and Tb show different oxidation states, 4+ and 3+ respectively. This leads to distinctly different electronic properties: the former compound is an insulator, while the latter is a metal. An extra electron which is donated by Ce to the polymeric C-N network is distributed across the network. This leads to a modification of the bond length in CeCN$ _5$ compared to TbCN$ _5$ . Still, the polymeric C-N networks can accommodate the different oxidation states in isostructural lanthanide-carbon-nitrogen (LnCN) compounds. Our results underline that LnCN compounds under high pressure offer a unique platform for probing the interplay between 4$ f$ -electron behavior and structural complexity.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Atomic-scale origin of charge density wave-driven metal-semiconductor transition in an incommensurately modulated metal-organic framework
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Ling Zhang, Zeyue Zhang, Liu He, Bin Jiang, Yingchao Wang, Jiaxiang Zhang, Huimin Qi, Chao Zhang, Jinkun Guo, Hao Chen, Yunlong Fan, Yanran Shen, Hongli Jia, Guobao Li, Yu-Qing Zheng, Julius J. Oppenheim, Tianyang Chen, Jian Wang, Lei Sun, Junliang Sun, Jin-Hu Dou
The intrinsic incommensurate charge density wave in metal-organic frameworks has remained elusive due to the lack of direct evidence linking atomic-scale structural modulation to macroscopic electronic properties. Using high-quality Pr3HHTP2 (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) single crystals as a model system, we precisely resolve, for the first time, the incommensurately modulated structure of a conductive metal-organic framework at 100 K (modulation vector q = 0.39143(12) c\ast) via temperature-dependent single-crystal X-ray diffraction. The subsequent observation of a reversible metal-semiconductor transition around 350 K, which perfectly synchronizes with the disappearance of the structural modulation, provides convincing evidence for the electronic origin of the lattice distortion. Guest water molecules stabilize the modulated phase by synergistically regulating the relative rotation of the linkers and the interlayer spacing, thereby optimizing the inter-linker interactions. This work establishes a concrete experimental criterion for one-dimensional charge density wave in metal-organic frameworks and provides an ideal platform for probing coupled electronic-lattice modulations.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Intrinsic i-wave altermagnetism in 2D graphene superlattices
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-04-22 20:00 EDT
Altermagnets feature unconventional magnetism due to their momentum-dependent spin splitting purely driven by magnetic order, for which a variety of transition-metal-based d-wave altermagnets have been proposed. However, carbon-based altermagnets in graphene structures remain elusive, even though magnetism in graphene nanostructures has been widely demonstrated. Here, we establish a symmetry-guided design principle to engineer i-wave altermagnets in graphene antidot superlattices and demonstrate the emergence of altermagnetic states in specific monolayer and bilayer graphene superlattices. By combining first principles methods and atomistic tight binding models, we show the appearance of an interaction-induced i-wave altermagnetic splitting, stemming from the intrinsic magnetic instability of 2D graphene antidot superlattices. Our work establishes a strategy to engineer i-wave altermagnetism in a graphene platform, putting forward a carbon-based platform for altermagnetic spintronics.
Materials Science (cond-mat.mtrl-sci)