CMP Journal 2025-06-18
Statistics
Nature: 19
Nature Physics: 1
Physical Review Letters: 17
Physical Review X: 1
arXiv: 68
Nature
Strategies for climate-resilient global wind and solar power systems
Original Paper | Climate-change adaptation | 2025-06-17 20:00 EDT
Dongsheng Zheng, Xizhe Yan, Dan Tong, Steven J. Davis, Ken Caldeira, Yuanyuan Lin, Yaqin Guo, Jingyun Li, Peng Wang, Liying Ping, Shijie Feng, Yang Liu, Jing Cheng, Deliang Chen, Kebin He, Qiang Zhang
Climate change may amplify the frequency and severity of supply-demand mismatches in future power systems with high shares of wind and solar energy1,2. Here, we use a dispatch optimization model to assess potential increases in hourly costs associated with such climate-intensified gaps under fixed, high penetrations of wind and solar generation. We further explore various strategies to enhance system resilience in the face of future climate change. We find that extreme periods–defined as hours in the upper decile of hourly costs (i.e., the most-costly 10% of hours)–are likely to become more costly in the future in most countries, mainly due to the increased need for investments in flexible energy capacity. For example, under the SSP126 scenario, 47 countries that together account for approximately 43.5% of global future electricity generation are projected to experience more than a 5% increase in average hourly costs during extreme periods, with the largest reaching up to 23.7%. Promisingly, the risk of rising costs could be substantially mitigated through tailored, country-specific strategies involving the coordinated implementation of multiple measures to address supply-demand imbalances and enhance system flexibility. Our findings provide critical insights for building future climate-resilient power systems while reducing system costs.
Climate-change adaptation, Climate-change mitigation, Energy economics, Energy supply and demand, Governance
Unsupervised pretraining in biological neural networks
Original Paper | Cortex | 2025-06-17 20:00 EDT
Lin Zhong, Scott Baptista, Rachel Gattoni, Jon Arnold, Daniel Flickinger, Carsen Stringer, Marius Pachitariu
Representation learning in neural networks may be implemented with supervised or unsupervised algorithms, distinguished by the availability of instruction. In the sensory cortex, perceptual learning drives neural plasticity1,2,3,4,5,6,7,8,9,10,11,12,13, but it is not known whether this is due to supervised or unsupervised learning. Here we recorded populations of up to 90,000 neurons simultaneously from the primary visual cortex (V1) and higher visual areas (HVAs) while mice learned multiple tasks, as well as during unrewarded exposure to the same stimuli. Similar to previous studies, we found that neural changes in task mice were correlated with their behavioural learning. However, the neural changes were mostly replicated in mice with unrewarded exposure, suggesting that the changes were in fact due to unsupervised learning. The neural plasticity was highest in the medial HVAs and obeyed visual, rather than spatial, learning rules. In task mice only, we found a ramping reward-prediction signal in anterior HVAs, potentially involved in supervised learning. Our neural results predict that unsupervised learning may accelerate subsequent task learning, a prediction that we validated with behavioural experiments.
Cortex, Learning algorithms, Sensory processing
Complete computational design of high-efficiency Kemp elimination enzymes
Original Paper | Biocatalysis | 2025-06-17 20:00 EDT
Dina Listov, Eva Vos, Gyula Hoffka, Shlomo Yakir Hoch, Andrej Berg, Shelly Hamer-Rogotner, Orly Dym, Shina Caroline Lynn Kamerlin, Sarel J. Fleishman
Until now, computationally designed enzymes exhibited low catalytic rates1,2,3,4,5 and required intensive experimental optimization to reach activity levels observed in comparable natural enzymes5,6,7,8,9. These results exposed limitations in design methodology and suggested critical gaps in our understanding of the fundamentals of biocatalysis10,11. We present a fully computational workflow for designing efficient enzymes in TIM-barrel folds using backbone fragments from natural proteins and without requiring optimization by mutant-library screening. Three Kemp eliminase designs exhibit efficiencies greater than 2,000 M-1 s-1. The most efficient shows more than 140 mutations from any natural protein, including a novel active site. It exhibits high stability (greater than 85 °C) and remarkable catalytic efficiency (12,700 M-1 s-1) and rate (2.8 s-1), surpassing previous computational designs by two orders of magnitude1,2,3,4,5. Furthermore, designing a residue considered essential in all previous Kemp eliminase designs increases efficiency to more than 105 M-1 s-1 and rate to 30 s-1, achieving catalytic parameters comparable to natural enzymes and challenging fundamental biocatalytic assumptions. By overcoming limitations in design methodology11, our strategy enables programming stable, high-efficiency, new-to-nature enzymes through a minimal experimental effort.
Biocatalysis, Enzyme mechanisms, Protein design, Structural biology
Optical nonlinearities in excess of 500 through sublattice reconstruction
Original Paper | Imaging techniques | 2025-06-17 20:00 EDT
Jiaye Chen, Chang Liu, Shibo Xi, Shengdong Tan, Qian He, Liangliang Liang, Xiaogang Liu
The ability of materials to respond to stimuli with significant optical nonlinearity is crucial for technological advancement and innovation1,2,3. Although photon-avalanche upconversion nanomaterials with nonlinearities exceeding 60 have been developed, further enhancement remains challenging4,5,6. Here we present a method to increase photon-avalanche nonlinearity beyond 500 by reconstructing the sublattice and extending the avalanche network. We demonstrate that lutetium substitution in the host material induces significant local crystal field distortions. These distortions strengthen cross-relaxation, the key process governing population accumulation. As a result, the optical nonlinearity is significantly amplified, enabling sub-diffraction imaging through single-beam scanning microscopy, achieving lateral and axial resolutions of 33 nm (about 1/32 of λExc) and 80 nm (around 1/13 of λExc), respectively (where λExc is the excitation wavelength). Moreover, our research shows regional differentiation within photon-avalanche nanocrystals, in which photon-avalanche performance varies across different regions at the single-nanoparticle level. This effect, coupled with extreme optical nonlinearity, enables visualization of nanoemitters at resolutions beyond their physical size using simple instrumentation. These advancements open new possibilities for super-resolution imaging, ultra-sensitive sensing, on-chip optical switching and infrared quantum counting.
Imaging techniques, Nonlinear optics
Bimodal centromeres in pentaploid dogroses shed light on their unique meiosis
Original Paper | Cytogenetics | 2025-06-17 20:00 EDT
V. Herklotz, M. Zhang, T. Nascimento, R. Kalfusová, J. Lunerová, J. Fuchs, D. Harpke, B. Huettel, U. Pfordt, V. Wissemann, A. Kovařík, A. Marques, C. M. Ritz
Sexual reproduction relies on meiotic chromosome pairing to form bivalents, a process that is complicated in polyploids owing to the presence of multiple subgenomes1. Uneven ploidy mostly results in sterility due to unbalanced chromosome pairing and segregation during meiosis. However, pentaploid dogroses (Rosa sect. Caninae; 2n = 5x = 35) achieve stable sexual reproduction through a unique mechanism: 14 chromosomes form bivalents and are transmitted biparentally, while the remaining 21 chromosomes are maternally inherited as univalents2,3. Despite being studied for over a century, the role of centromeres in this process has remained unclear. Here we analyse haplotype-resolved chromosome-level genome assemblies for three pentaploid dogroses. Subgenome phasing revealed a bivalent-forming subgenome with two highly homozygous chromosome sets and three divergent subgenomes lacking homologous partners, therefore explaining their meiotic behaviour. Comparative analyses of chromosome synteny, phylogenetic relationships and centromere composition indicate that the subgenomes originated from two divergent clades of the genus Rosa. Pollen genome analysis shows that subgenomes from different evolutionary origins form bivalents, supporting multiple origins of dogroses and highlighting variation in subgenome contributions. We reveal that bivalent-forming centromeres are enriched with ATHILA retrotransposons, contrasting with larger tandem-repeat-based centromeres mainly found in univalents. This centromere structural bimodality possibly contributes to univalent drive during female meiosis. Our findings provide insights into the unique reproductive strategies of dogroses, advancing our understanding of genome evolution, centromere diversity and meiotic mechanisms in organisms with asymmetrical inheritance systems.
Cytogenetics, Evolutionary genetics, Genomics, Plant hybridization, Polyploidy in plants
Kupffer cell programming by maternal obesity triggers fatty liver disease
Original Paper | Haematopoiesis | 2025-06-17 20:00 EDT
Hao Huang, Nora R. Balzer, Lea Seep, Iva Splichalova, Nelli Blank-Stein, Maria Francesca Viola, Eliana Franco Taveras, Kerim Acil, Diana Fink, Franzisca Petrovic, Nikola Makdissi, Seyhmus Bayar, Katharina Mauel, Carolin Radwaniak, Jelena Zurkovic, Amir H. Kayvanjoo, Klaus Wunderling, Malin Jessen, Mohamed H. Yaghmour, Lukas Kenner, Thomas Ulas, Stephan Grein, Joachim L. Schultze, Charlotte L. Scott, Martin Guilliams, Zhaoyuan Liu, Florent Ginhoux, Marc D. Beyer, Christoph Thiele, Felix Meissner, Jan Hasenauer, Dagmar Wachten, Elvira Mass
Kupffer cells (KCs) are tissue-resident macrophages that colonize the liver early during embryogenesis1. Upon liver colonization, KCs rapidly acquire a tissue-specific transcriptional signature, mature alongside the developing liver and adapt to its functions1,2,3. Throughout development and adulthood, KCs perform distinct core functions that are essential for liver and organismal homeostasis, including supporting fetal erythropoiesis, postnatal erythrocyte recycling and liver metabolism4. However, whether perturbations of macrophage core functions during development contribute to or cause disease at postnatal stages is poorly understood. Here, we utilize a mouse model of maternal obesity to perturb KC functions during gestation. We show that offspring exposed to maternal obesity develop fatty liver disease, driven by aberrant developmental programming of KCs that persists into adulthood. Programmed KCs promote lipid uptake by hepatocytes through apolipoprotein secretion. KC depletion in neonate mice born to obese mothers, followed by replenishment with naive monocytes, rescues fatty liver disease. Furthermore, genetic ablation of the gene encoding hypoxia-inducible factor-α (HIF1α) in macrophages during gestation prevents the metabolic programming of KCs from oxidative phosphorylation to glycolysis, thereby averting the development of fatty liver disease. These results establish developmental perturbation of KC functions as a causal factor in fatty liver disease in adulthood and position fetal-derived macrophages as critical intergenerational messengers within the concept of developmental origins of health and diseases5.
Haematopoiesis, Innate immunity
Allosteric modulation and biased signalling at free fatty acid receptor 2
Original Paper | Cryoelectron microscopy | 2025-06-17 20:00 EDT
Xuan Zhang, Abdul-Akim Guseinov, Laura Jenkins, Alice Valentini, Sara Marsango, Katrine Schultz-Knudsen, Trond Ulven, Elisabeth Rexen Ulven, Irina G. Tikhonova, Graeme Milligan, Cheng Zhang
Free fatty acid receptor 2 (FFA2) is a G protein-coupled receptor (GPCR) that is a primary sensor for short-chain fatty acids produced by gut microbiota. Consequently, FFA2 is a promising drug target for immunometabolic disorders1,2,3,4. Here we report cryogenic electronic microscopy structures of FFA2 in complex with two G proteins and three distinct classes of positive allosteric modulators (PAMs), and describe noncanonical activation mechanisms that involve conserved structural features of class A GPCRs. Two PAMs disrupt the E/DRY activation microswitch5 and stabilize the conformation of intracellular loop 2 by binding to lipid-facing pockets near the cytoplasmic side of the receptor. By contrast, the third PAM promotes the separation of transmembrane helices 6 and 7 by interacting with transmembrane helix 6 at the receptor-lipid interface. Molecular dynamic simulations and mutagenesis experiments confirm these noncanonical activation mechanisms. Furthermore, we demonstrate the molecular basis for the Gi versus Gq bias, which is due to distinct conformations of intracellular loop 2 stabilized by different PAMs. These findings provide a framework for the design of tailored GPCR modulators, with implications that extend beyond FFA2 to the broader field of GPCR drug discovery.
Cryoelectron microscopy, Receptor pharmacology
Machine-learning design of ductile FeNiCoAlTa alloys with high strength
Original Paper | Materials science | 2025-06-17 20:00 EDT
Yasir Sohail, Chongle Zhang, Dezhen Xue, Jinyu Zhang, Dongdong Zhang, Shaohua Gao, Yang Yang, Xiaoxuan Fan, Hang Zhang, Gang Liu, Jun Sun, En Ma
The pursuit of strong yet ductile alloys has been ongoing for centuries. However, for all alloys developed thus far, including recent high-entropy alloys, those possessing good tensile ductility rarely approach 2-GPa yield strength at room temperature. The few that do are mostly ultra-strong steels1,2,3; however, their stress-strain curves exhibit plateaus and serrations because their tensile flow suffers from plastic instability (such as Lüders strains)1,2,3,4, and the elongation is pseudo-uniform at best. Here we report that a group of carefully engineered multi-principal-element alloys, with a composition of Fe35Ni29Co21Al12Ta3 designed by means of domain knowledge-informed machine learning, can be processed to reach an unprecedented range of simultaneously high strength and ductility. An example of this synergy delivers 1.8-GPa yield strength combined with 25% truly uniform elongation. We achieved strengthening by pushing microstructural heterogeneities to the extreme through unusually large volume fractions of not only coherent L12 nanoprecipitates but also incoherent B2 microparticles. The latter, being multicomponent with a reduced chemical ordering energy, is a deformable phase that accumulates dislocations inside to help sustain a high strain hardening rate that prolongs uniform elongation.
Materials science, Metals and alloys
Impacts of climate change on global agriculture accounting for adaptation
Original Paper | Agriculture | 2025-06-17 20:00 EDT
Andrew Hultgren, Tamma Carleton, Michael Delgado, Diana R. Gergel, Michael Greenstone, Trevor Houser, Solomon Hsiang, Amir Jina, Robert E. Kopp, Steven B. Malevich, Kelly E. McCusker, Terin Mayer, Ishan Nath, James Rising, Ashwin Rode, Jiacan Yuan
Climate change threatens global food systems1, but the extent to which adaptation will reduce losses remains unknown and controversial2. Even within the well-studied context of US agriculture, some analyses argue that adaptation will be widespread and climate damages small3,4, whereas others conclude that adaptation will be limited and losses severe5,6. Scenario-based analyses indicate that adaptation should have notable consequences on global agricultural productivity7,8,9, but there has been no systematic study of how extensively real-world producers actually adapt at the global scale. Here we empirically estimate the impact of global producer adaptations using longitudinal data on six staple crops spanning 12,658 regions, capturing two-thirds of global crop calories. We estimate that global production declines 5.5 × 1014 kcal annually per 1 °C global mean surface temperature (GMST) rise (120 kcal per person per day or 4.4% of recommended consumption per 1 °C; P < 0.001). We project that adaptation and income growth alleviate 23% of global losses in 2050 and 34% at the end of the century (6% and 12%, respectively; moderate-emissions scenario), but substantial residual losses remain for all staples except rice. In contrast to analyses of other outcomes that project the greatest damages to the global poor10,11, we find that global impacts are dominated by losses to modern-day breadbaskets with favourable climates and limited present adaptation, although losses in low-income regions losses are also substantial. These results indicate a scale of innovation, cropland expansion or further adaptation that might be necessary to ensure food security in a changing climate.
Agriculture, Climate-change adaptation, Climate-change impacts, Environmental economics, Interdisciplinary studies
Gut inflammation promotes microbiota-specific CD4 T cell-mediated neuroinflammation
Original Paper | Autoimmunity | 2025-06-17 20:00 EDT
Zachary White, Ivan Cabrera, Linghan Mei, Margarette Clevenger, Andrea Ochoa-Raya, Isabel Kapustka, Joseph R. Dominguez, Jinyan Zhou, Kevin P. Koster, Shehata Anwar, Qianxun Wang, Charles Ng, Shoko Sagoshi, Takashi Matsuo, Dulari Jayawardena, Seung Hyeon Kim, Takahiro Kageyama, Benjamin J. Mitchell, Dante Rivera, Pradeep K. Dudeja, Sarah E. Lutz, Ki-Wook Kim, Akira Yoshii, Nicolas Chevrier, Makoto Inoue, Teruyuki Sano
The microbiota has been recognized as a critical contributor to various diseases1, with multiple reports of changes in the composition of the gut microbiome in contexts such as inflammatory bowel disease2,3 and neurodegenerative diseases4. These microbial shifts can exert systemic effects by altering the release of specific metabolites into the bloodstream5,6, and the gastrointestinal microbiota has also been reported to exhibit immunomodulatory activity through the activation of innate and adaptive immunity7,8. However, it remains unclear how the microbiota contributes to inflammation in the central nervous system (CNS), where these microorganisms are typically absent. Here we report that T cells that recognize gut-colonizing segmented filamentous bacteria can induce inflammation in the mouse intestine and CNS in the absence of functional regulatory T cells. Gut commensal-specific CD4 T cells (Tcomm cells) that are dysregulated in the inflamed gut can become licensed to infiltrate into the CNS regardless of their antigen specificity and have the potential to be re-stimulated by host protein-derived antigens in the CNS via molecular mimicry, whereupon they produce high levels of GM-CSF, IFNγ and IL-17A, triggering neurological damage. These infiltrated Tcomm cells initiate CNS inflammation by activating microglia through their IL-23R-dependent encephalitogenic programme and their IL-23R-independent GM-CSF production. Together, our findings reveal potential mechanisms whereby perturbation of Tcomm cells can contribute to extraintestinal inflammation.
Autoimmunity, Neuroimmunology
Targeting de novo purine biosynthesis for tuberculosis treatment
Original Paper | Antibacterial drug resistance | 2025-06-17 20:00 EDT
Dirk A. Lamprecht, Richard J. Wall, Annelies Leemans, Barry Truebody, Joke Sprangers, Patricia Fiogbe, Cadi Davies, Jennefer Wetzel, Stijn Daems, William Pearson, Vanessa Pillay, Samantha Saylock, M. Daniel Ricketts, Ellie Davis, Adam Huff, Tsehai Grell, Shiming Lin, Michelle Gerber, Ann Vos, John Dallow, Sam J. Willcocks, Christine Roubert, Stéphanie Sans, Amandine Desorme, Nicolas Chappat, Aurélie Ray, Mariana Pereira Moraes, Tracy Washington, Hope D’Erasmo, Pavankumar Sancheti, Melissa Everaerts, Mario Monshouwer, Jorge Esquivias, Gerald Larrouy-Maumus, Ruxandra Draghia Akli, Helen Fletcher, Alexander S. Pym, Bree B. Aldridge, Jansy P. Sarathy, Kathleen W. Clancy, Bart Stoops, Neeraj Dhar, Adrie J. C. Steyn, Paul Jackson, Clara Aguilar-Pérez, Anil Koul
Tuberculosis remains the leading cause of death from an infectious disease1,2. Here we report the discovery of a first-in-class small-molecule inhibitor targeting PurF, the first enzyme in the mycobacterial de novo purine biosynthesis pathway. The lead candidate, JNJ-6640, exhibited nanomolar bactericidal activity in vitro. Comprehensive genetic and biochemical approaches confirmed that JNJ-6640 was highly selective for mycobacterial PurF. Single-cell-level microscopy demonstrated a downstream effect on DNA replication. We determined the physiologically relevant concentrations of nucleobases in human and mouse lung tissue, showing that these levels were insufficient to salvage PurF inhibition. Indeed, proof-of-concept studies using a long-acting injectable formulation demonstrated the in vivo efficacy of the compound. Finally, we show that inclusion of JNJ-6640 could have a crucial role in improving current treatment regimens for drug-resistant tuberculosis. Together, we demonstrate that JNJ-6640 is a promising chemical lead and that targeting de novo purine biosynthesis represents a novel strategy for tuberculosis drug development.
Antibacterial drug resistance, Antibiotics, Pharmaceutics, Target identification, Tuberculosis
Morphodynamics of human early brain organoid development
Original Paper | Image processing | 2025-06-17 20:00 EDT
Akanksha Jain, Gilles Gut, Fátima Sanchis-Calleja, Reto Tschannen, Zhisong He, Nicolas Luginbühl, Fides Zenk, Antonius Chrisnandy, Simon Streib, Christoph Harmel, Ryoko Okamoto, Malgorzata Santel, Makiko Seimiya, René Holtackers, Juliane K. Rohland, Sophie Martina Johanna Jansen, Matthias P. Lutolf, J. Gray Camp, Barbara Treutlein
Brain organoids enable the mechanistic study of human brain development and provide opportunities to explore self-organization in unconstrained developmental systems1,2,3. Here we establish long-term, live light-sheet microscopy on unguided brain organoids generated from fluorescently labelled human induced pluripotent stem cells, which enables tracking of tissue morphology, cell behaviours and subcellular features over weeks of organoid development4. We provide a novel dual-channel, multi-mosaic and multi-protein labelling strategy combined with a computational demultiplexing approach to enable simultaneous quantification of distinct subcellular features during organoid development. We track actin, tubulin, plasma membrane, nucleus and nuclear envelope dynamics, and quantify cell morphometric and alignment changes during tissue-state transitions including neuroepithelial induction, maturation, lumenization and brain regionalization. On the basis of imaging and single-cell transcriptome modalities, we find that lumenal expansion and cell morphotype composition within the developing neuroepithelium are associated with modulation of gene expression programs involving extracellular matrix pathway regulators and mechanosensing. We show that an extrinsically provided matrix enhances lumen expansion as well as telencephalon formation, and unguided organoids grown in the absence of an extrinsic matrix have altered morphologies with increased neural crest and caudalized tissue identity. Matrix-induced regional guidance and lumen morphogenesis are linked to the WNT and Hippo (YAP1) signalling pathways, including spatially restricted induction of the WNT ligand secretion mediator (WLS) that marks the earliest emergence of non-telencephalic brain regions. Together, our work provides an inroad into studying human brain morphodynamics and supports a view that matrix-linked mechanosensing dynamics have a central role during brain regionalization.
Image processing, Morphogenesis, Multicellular systems, Neural stem cells, Time-lapse imaging
Bioinspired capillary force-driven super-adhesive filter
Original Paper | Fluids | 2025-06-17 20:00 EDT
Junyong Park, Chan Sik Moon, Ji Min Lee, Sazzadul A. Rahat, Sang Moon Kim, Jonathan T. Pham, Michael Kappl, Hans-Jürgen Butt, Sanghyuk Wooh
Capturing particles with low, nanonewton-scale adhesion is an ongoing challenge for conventional air filters1,2. Inspired by the natural filtration abilities of mucus-coated nasal hairs3,4, we introduce an efficient, biomimetic filter that exploits a thin liquid coating. Here we show that a stable thin liquid layer is formed on several filter media that generates enhanced particulate adhesion, driven by micronewton to sub-micronewton capillary forces5,6. Enhanced particle adhesion increases the filtration of airborne particulates while maintaining air permeability, providing longer filter lifetime and increased energy savings. Moreover, strong adhesion of the captured particles enables effective filtration under high-speed airflow as well as suppression of particle redispersion. We anticipate that these filters with thin liquid layers afford a new way to innovate particulate matter filtering systems.
Fluids, Mechanical engineering, Pollution remediation, Wetting
Bogong moths use a stellar compass for long-distance navigation at night
Original Paper | Animal behaviour | 2025-06-17 20:00 EDT
David Dreyer, Andrea Adden, Hui Chen, Barrie Frost, Henrik Mouritsen, Jingjing Xu, Ken Green, Mary Whitehouse, Javaan Chahl, Jesse Wallace, Gao Hu, James Foster, Stanley Heinze, Eric Warrant
Each spring, billions of Bogong moths escape hot conditions across southeast Australia by migrating up to 1,000 km to a place that they have never previously visited–a limited number of cool caves in the Australian Alps, historically used for aestivating over summer1,2. At the beginning of autumn, the same individuals make a return migration to their breeding grounds to reproduce and die. Here we show that Bogong moths use the starry night sky as a compass to distinguish between specific geographical directions, thereby navigating in their inherited migratory direction towards their distant goal. By tethering spring and autumn migratory moths in a flight simulator3,4,5, we found that, under naturalistic moonless night skies and in a nulled geomagnetic field (disabling the moth’s known magnetic sense4), moths flew in their seasonally appropriate migratory directions. Visual interneurons in different regions of the moth’s brain responded specifically to rotations of the night sky and were tuned to a common sky orientation, firing maximally when the moth was headed southwards. Our results suggest that Bogong moths use stellar cues and the Earth’s magnetic field to create a robust compass system for long-distance nocturnal navigation towards a specific destination.
Animal behaviour, Entomology
Major expansion in the human niche preceded out of Africa dispersal
Original Paper | Archaeology | 2025-06-17 20:00 EDT
Emily Y. Hallett, Michela Leonardi, Jacopo Niccolò Cerasoni, Manuel Will, Robert Beyer, Mario Krapp, Andrew W. Kandel, Andrea Manica, Eleanor M. L. Scerri
All contemporary Eurasians trace most of their ancestry to a small population that dispersed out of Africa about 50,000 years ago (ka)1,2,3,4,5,6,7,8,9. By contrast, fossil evidence attests to earlier migrations out of Africa10,11,12,13,14,15. These lines of evidence can only be reconciled if early dispersals made little to no genetic contribution to the later, major wave. A key question therefore concerns what factors facilitated the successful later dispersal that led to long-term settlement beyond Africa. Here we show that a notable expansion in human niche breadth within Africa precedes this later dispersal. We assembled a pan-African database of chronometrically dated archaeological sites and used species distribution models (SDMs) to quantify changes in the bioclimatic niche over the past 120,000 years. We found that the human niche began to expand substantially from 70 ka and that this expansion was driven by humans increasing their use of diverse habitat types, from forests to arid deserts. Thus, humans dispersing out of Africa after 50 ka were equipped with a distinctive ecological flexibility among hominins as they encountered climatically challenging habitats, providing a key mechanism for their adaptive success.
Archaeology, Ecological modelling, Evolutionary ecology
In vivo mapping of mutagenesis sensitivity of human enhancers
Original Paper | Embryology | 2025-06-17 20:00 EDT
Michael Kosicki, Boyang Zhang, Vivian Hecht, Anusri Pampari, Laura E. Cook, Neil Slaven, Jennifer A. Akiyama, Ingrid Plajzer-Frick, Catherine S. Novak, Momoe Kato, Stella Tran, Riana D. Hunter, Kianna von Maydell, Sarah Barton, Erik Beckman, Yiwen Zhu, Diane E. Dickel, Anshul Kundaje, Axel Visel, Len A. Pennacchio
Distant-acting enhancers are central to human development1. However, our limited understanding of their functional sequence features prevents the interpretation of enhancer mutations in disease2. Here we determined the functional sensitivity to mutagenesis of human developmental enhancers in vivo. Focusing on seven enhancers that are active in the developing brain, heart, limb and face, we created over 1,700 transgenic mice for over 260 mutagenized enhancer alleles. Systematic mutation of 12-base-pair blocks collectively altered each sequence feature in each enhancer at least once. We show that 69% of all blocks are required for normal in vivo activity, with mutations more commonly resulting in loss (60%) than in gain (9%) of function. Using predictive modelling, we annotated critical nucleotides at the base-pair resolution. The vast majority of motifs predicted by these machine learning models (88%) coincided with changes in in vivo function, and the models showed considerable sensitivity, identifying 59% of all functional blocks. Taken together, our results reveal that human enhancers contain a high density of sequence features that are required for their normal in vivo function and provide a rich resource for further exploration of human enhancer logic.
Embryology, Epigenomics, Gene regulation, Machine learning
Single-cell transcriptomic and chromatin dynamics of the human brain in PTSD
Original Paper | Molecular neuroscience | 2025-06-17 20:00 EDT
Ahyeon Hwang, Mario Skarica, Siwei Xu, Jensine Coudriet, Che Yu Lee, Lin Lin, Rosemarie Terwilliger, Alexa-Nicole Sliby, Jiawei Wang, Tuan Nguyen, Hongyu Li, Min Wu, Yi Dai, Ziheng Duan, Shushrruth Sai Srinivasan, Xiangyu Zhang, Yingxin Lin, Dianne Cruz, P. J. Michael Deans, Victor E. Alvarez, David Benedek, Alicia Che, Dianne A. Cruz, David A. Davis, Ellen Hoffman, Alfred Kaye, Adam T. Labadorf, Terence M. Keane, Mark W. Logue, Ann McKee, Brian Marx, Mark W. Miller, Crystal Noller, Janitza Montalvo-Ortiz, Meghan Pierce, William K. Scott, Paula Schnurr, Krista DiSano, Thor Stein, Robert Ursano, Erika J. Wolf, Bertrand R. Huber, Daniel Levey, Jill R. Glausier, David A. Lewis, Joel Gelernter, Paul E. Holtzheimer, Matthew J. Friedman, Mark Gerstein, Nenad Sestan, Kristen J. Brennand, Ke Xu, Hongyu Zhao, John H. Krystal, Keith A. Young, Douglas E. Williamson, Alicia Che, Jing Zhang, Matthew J. Girgenti
Post-traumatic stress disorder (PTSD) is a polygenic disorder occurring after extreme trauma exposure. Recent studies have begun to detail the molecular biology of PTSD. However, given the array of PTSD-perturbed molecular pathways identified so far1, it is implausible that a single cell type is responsible. Here we profile the molecular responses in over two million nuclei from the dorsolateral prefrontal cortex of 111 human brains, collected post-mortem from individuals with and without PTSD and major depressive disorder. We identify neuronal and non-neuronal cell-type clusters, gene expression changes and transcriptional regulators, and map the epigenomic regulome of PTSD in a cell-type-specific manner. Our analysis revealed PTSD-associated gene alterations in inhibitory neurons, endothelial cells and microglia and uncovered genes and pathways associated with glucocorticoid signalling, GABAergic transmission and neuroinflammation. We further validated these findings using cell-type-specific spatial transcriptomics, confirming disruption of key genes such as SST and FKBP5. By integrating genetic, transcriptomic and epigenetic data, we uncovered the regulatory mechanisms of credible variants that disrupt PTSD genes, including ELFN1, MAD1L1 and KCNIP4, in a cell-type-specific context. Together, these findings provide a comprehensive characterization of the cell-specific molecular regulatory mechanisms that underlie the persisting effects of traumatic stress response on the human prefrontal cortex.
Molecular neuroscience, Post-traumatic stress disorder
Vertically stacked monolithic perovskite colour photodetectors
Original Paper | Electrical and electronic engineering | 2025-06-17 20:00 EDT
Sergey Tsarev, Daria Proniakova, Xuqi Liu, Erfu Wu, Gebhard J. Matt, Kostiantyn Sakhatskyi, Lorenzo L. A. Ferraresi, Radha Kothandaraman, Fan Fu, Ivan Shorubalko, Sergii Yakunin, Maksym V. Kovalenko
Modern colour image sensors face challenges in further improving sensitivity and image quality because of inherent limitations in light utilization efficiency1. A major factor contributing to these limitations is the use of passive optical filters, which absorb and dissipate a substantial amount of light, thereby reducing the efficiency of light capture2. On the contrary, active optical filtering in Foveon-type vertically stacked architectures still struggles to deliver optimal performance owing to their lack of colour selectivity, making them inefficient for precise colour imaging3. Here we introduce an innovative architecture for colour sensor arrays that uses multilayer monolithically stacked lead halide perovskite thin-film photodetectors. Perovskite bandgap tunability4 is utilized to selectively absorb the visible light spectrum’s red, green and blue regions, eliminating the need for colour filters. External quantum efficiencies of 50%, 47% and 53% are demonstrated for the red, green and blue channels, respectively, as well as a colour accuracy of 3.8% in ΔELab outperforming the state-of-the-art colour-filter array and Foveon-type photosensors. The image sensor design improves light utilization in colour sensors and paves the way for the next generation of highly sensitive, artefact-free images with enhanced colour fidelity.
Electrical and electronic engineering, Energy harvesting, Optical materials and structures, Optical sensors
R9AP is a common receptor for EBV infection in epithelial cells and B cells
Original Paper | Herpes virus | 2025-06-17 20:00 EDT
Yan Li, Hua Zhang, Cong Sun, Xiao-Dong Dong, Chu Xie, Yuan-Tao Liu, Ruo-Bin Lin, Xiang-Wei Kong, Zhu-Long Hu, Xiao-Yan Ma, Dan-Ling Dai, Qian-Ying Zhu, Yu-Chun Li, Ying Li, Shang-Xin Liu, Li Yuan, Peng-Hui Zhou, Song Gao, Ya-Ping Tang, Jin-Ying Yang, Ping Han, Andrew T. McGuire, Bo Zhao, Jin-Xin Bei, Erle Robertson, Yi-Xin Zeng, Qian Zhong, Mu-Sheng Zeng
Epstein-Barr virus (EBV) persistently infects more than 90% of the human population, causing infectious mononucleosis1, susceptibility to autoimmune diseases2 and multiple malignancies of epithelial or B cell-origin3. EBV infects epithelial cells and B cells through interaction between viral glycoproteins and different host receptors4, but it has remained unknown whether a common receptor mediates infection of its two major host cell targets. Here, we establish R9AP as a crucial EBV receptor for entry into epithelial and B cells. R9AP silencing or knockout, R9AP-derived peptide and R9AP monoclonal antibody each significantly inhibit, whereas R9AP overexpression promotes, EBV uptake into both cell types. R9AP binds directly to the EBV glycoprotein gH/gL complex to initiate gH/gL-gB-mediated membrane fusion. Notably, the interaction of R9AP with gH/gL is inhibited by the highly competitive gH/gL-neutralizing antibody AMMO1, which blocks EBV epithelial and B cell entry. Moreover, R9AP mediates viral and cellular membrane fusion in cooperation with EBV gp42-human leukocyte antigen class II or gH/gL-EPHA2 complexes in B cells or epithelial cells, respectively. We propose R9AP as the crucial common receptor of B cells and epithelial cells and a potential prophylactic and vaccine target for EBV.
Herpes virus, Infection, Viral infection
Nature Physics
Feedback between F-actin organization and active stress governs criticality and energy localization in the cell cytoskeleton
Original Paper | Biological physics | 2025-06-17 20:00 EDT
Zachary Gao Sun, Nathan Zimmerberg, Patrick Kelly, Carlos Floyd, Garegin Papoian, Michael Murrell
Self-organized criticality can occur in earthquakes, avalanches and biological processes, and is characterized by intermittent, scale-free energy dissipation. In living cells, the actin cytoskeleton undergoes dynamic structural reorganization, particularly during migration and division, where molecular motors generate mechanical stresses that drive large dissipative events. However, the mechanisms governing these critical transitions remain unclear. Here we show that cytoskeletal criticality emerges from the interplay between F-actin organization and active stress generation. Our study focuses on a minimal actomyosin system in vitro, which is composed of F-actin filaments, myosin II motors and nucleation-promoting factors. By systematically varying the actin connectivity and nematic order, we demonstrate that ordered and sparsely connected networks exhibit exponential stress dissipation, whereas disordered and highly connected networks show heavy-tailed distributions of energy release and the 1/f noise characteristic of self-organized criticality. Increased disorder leads to stress localization, shifting force propagation into stiffer mechanical modes, reminiscent of Anderson localization in condensed-matter systems. Furthermore, we show that network architecture directly regulates the myosin II filament size, establishing a chemical-mechanical feedback loop that modulates criticality. Our findings provide insights into the collective cytoskeletal dynamics, energy localization and cellular self-organization.
Biological physics, Phase transitions and critical phenomena
Physical Review Letters
Searching for Axionlike Particles with X-Ray Observations of Alpha Centauri
Research article | Particle astrophysics | 2025-06-17 06:00 EDT
Yu-Xuan Chen, Lei Lei, Zi-Qing Xia, Ziwei Wang, Yue-Lin Sming Tsai, and Yi-Zhong Fan
We investigate the production of axionlike particles (ALPs) in stellar cores, where they interact with electromagnetic fields and electrons, with typical masses between $\mathcal{O}(0.1)$ and $\mathcal{O}(10)\text{ }\text{ }\mathrm{keV}$. These low-energy ALPs are gravitationally trapped in the orbits of stars and subsequently decay into two photons that we detect as monochromatic x-ray lines. We propose to search for these gravitationally trapped ALPs in the Alpha Centauri binary system, our closest stellar neighbor, using sensitive x-ray detectors like Chandra and eROSITA. Our search for ALP decay signals in the energy range of 0.2 keV to 10 keV yielded null results, thus establishing the most stringent limits on ALP interactions to date. In the case of ALP-electron coupling ${g}{aee}\le {10}^{- 15}$, we have improved the limits on the ALP-photon coupling ${g}{a\gamma \gamma }$ in ALP mass range between 0.25 keV and 5 keV, compared to previous measurements, including those from GW170817, SN 2023ixf, and other sources, and specially the improvement reaches about 2 orders of magnitude at the mass of 2 keV. Even tighter constraints are set for larger ${g}_{aee}$.
Phys. Rev. Lett. 134, 241001 (2025)
Particle astrophysics
Bound States of the Schwarzschild Black Hole
Research article | Classical black holes | 2025-06-17 06:00 EDT
Sebastian H. Völkel
Understanding the physical significance and spectral stability of black hole quasinormal modes is fundamental to high-precision spectroscopy with future gravitational wave detectors. Inspired by Mashhoon’s idea of relating quasinormal modes of black holes with their equivalent bound states in an inverted potential, we investigate, for the first time, energy levels and eigenfunctions of the Schwarzschild black hole quantitatively. While quasinormal modes describe the characteristic damped oscillations of a black hole, the bound states of the inverted potential are qualitatively more similar to those of the hydrogen atom. Although the physical interpretation of these states may initially be of more academic interest, it furthers our understanding of open problems related to quasinormal modes in a similar spirit to Maggiore’s interpretation of the Schwarzschild quasinormal mode spectrum. One surprising insight from the explicit calculation of bound states is that eigenfunctions corresponding to quasinormal mode overtones become rapidly delocalized and extremely loosely bound. This observation raises immediate questions about the common interpretation of quasinormal modes as excitations of the light ring region. Closely related, as a second application, we also explore the spectral stability of bound states and demonstrate that they can provide complementary insights into the quasinormal mode spectrum.
Phys. Rev. Lett. 134, 241401 (2025)
Classical black holes, General relativity, Gravitation, Gravitational waves
Lanczos Algorithm, the Transfer Matrix, and the Signal-to-Noise Problem
Research article | Bound states | 2025-06-17 06:00 EDT
Michael L. Wagman
This Letter introduces a method for determining the energy spectrum of lattice quantum chromodynamics by applying the Lanczos algorithm to the transfer matrix and using a bootstrap generalization of the Cullum-Willoughby method to filter out spurious eigenvalues. Proof-of-principle analyses of the simple harmonic oscillator and the lattice quantum chromodynamics proton mass demonstrate that this method provides faster ground-state convergence than the ‘’effective mass,’’ which is related to the power-iteration algorithm. Lanczos provides more accurate energy estimates than multistate fits to correlation functions with small imaginary times while achieving comparable statistical precision. Two-sided error bounds are computed for Lanczos results and guarantee that excited-state effects cannot shift Lanczos results far outside their statistical uncertainties.
Phys. Rev. Lett. 134, 241901 (2025)
Bound states, Color confinement, Gauge theories, Lattice QCD, Lattice field theory, Multiquark bound states, Noise, Path integrals, Quantum chromodynamics, Quantum field theory, Quantum statistical mechanics, Quantum thermodynamics, Strong interaction
Observation of Charmonium ${h}{c}$ Radiative Decays to Multiple Light Hadrons and the Tensor State ${f}{2}(1270)$
Research article | Branching fraction | 2025-06-17 06:00 EDT
M. Ablikim et al. (BESIII Collaboration)
Using $\psi (3686)\rightarrow {\pi }^{0}{h}{c}$ decays from a data sample of $(27.12\pm{}0.14)\times{}{10}^{8}\text{ }\text{ }\psi (3686)$ events collected by the BESIII detector at the BEPCII collider, ${h}{c}$ radiative decays to multiple light hadrons below $2.8\text{ }\text{ }\mathrm{GeV}/{c}^{2}$—$\gamma {\pi }^{+}{\pi }^{- }$, $\gamma {\pi }^{+}{\pi }^{- }\eta $, $\gamma 2({\pi }^{+}{\pi }^{- })$, and $\gamma p\overline{p}$—are observed for the first time, each with a significance greater than $5\sigma $. The corresponding branching fractions are measured. Furthermore, intermediate states are investigated, leading to the first observation of the decay process of ${h}{c}\rightarrow \gamma {f}{2}(1270)\rightarrow \gamma {\pi }^{+}{\pi }^{- }$ with a significance of $5.1\sigma $. This observation represents the first instance of ${h}_{c}$ radiative decay to a tensor state.
Phys. Rev. Lett. 134, 241902 (2025)
Branching fraction, Particle decays, Mesons, Lepton colliders
Final Results of the Majorana Demonstrator’s Search for Double-Beta Decay of $^{76}\mathrm{Ge}$ to Excited States of $^{76}\mathrm{Se}$
Research article | Double beta decay | 2025-06-17 06:00 EDT
I. J. Arnquist et al. (Majorana Collaboration)
$^{76}\mathrm{Ge}$ can $\beta \beta $ decay into three possible excited states of $^{76}\mathrm{Se}$, with the emission of two or, if the neutrino is Majorana, zero neutrinos. None of these six transitions have yet been observed. The Majorana Demonstrator was designed to study $\beta \beta $ decay of $^{76}\mathrm{Ge}$ using a low background array of high purity germanium detectors. With 98.2 kg-y of isotopic exposure, the demonstrator sets the strongest half-life limits to date for all six transition modes. For $2\nu \beta \beta $ to the ${0}{1}^{+}$ state of $^{76}\mathrm{Se}$, this search has begun to probe for the first time half-life values predicted using modern many-body nuclear theory techniques, setting a limit of ${T}{1/2}>1.5\times{}{10}^{24}\text{ }\text{ }\mathrm{y}$ (90% CL).
Phys. Rev. Lett. 134, 242501 (2025)
Double beta decay, Neutrinoless double beta decay, Majorana neutrinos, Neutrinos, 59 ≤ A ≤ 89, Baryon & lepton number symmetries, Radiation detectors, Solid-state detectors
Confinement-Induced Resonances in Spherical Shell Traps
Research article | Atom & ion trapping & guiding | 2025-06-17 06:00 EDT
C. Moritz Carmesin and Maxim A. Efremov
The energy spectrum and corresponding wave functions of two bosonic particles confined in a spherically symmetric shell trap and interacting via a three-dimensional zero-range potential are computed. Confinement-induced resonances, originating entirely from the strong coupling of the relative and center-of-mass motions of the two particles, are identified as avoided crossings for certain values of the shell radius. By working close to the found resonances, these results offer a new way to control the atom-atom interaction in an atomic gas by tuning only the geometrical parameters of the shell.
Phys. Rev. Lett. 134, 243401 (2025)
Atom & ion trapping & guiding, Bose gases, Cold atoms & matter waves
Squeezing at the Normal-Mode Splitting Frequency of a Nonlinear Coupled Cavity
Research article | Gravitational waves | 2025-06-17 06:00 EDT
Jonas Junker, Jiayi Qin, Vaishali B. Adya, Nutsinee Kijbunchoo, Sheon S. Y. Chua, Terry G. McRae, Bram J. J. Slagmolen, and David E. McClelland
Coupled optical cavities, which support normal modes, play a critical role in optical filtering, sensing, slow-light generation, and quantum state manipulation. Recent theoretical work has proposed incorporating nonlinear materials into these systems to enable novel quantum technologies. Here, we report the first experimental demonstration of squeezing generated in a quantum-enhanced coupled-cavity system, achieving a quantum noise reduction of 3.3 dB around the normal-mode splitting frequency of 7.47 MHz. We provide a comprehensive analysis of the system’s loss mechanisms and performance limitations, validating theoretical predictions. Our results underscore the promise of coupled-cavity squeezers for advanced quantum applications, including gravitational wave detection and precision sensing.
Phys. Rev. Lett. 134, 243603 (2025)
Gravitational waves, Nonlinear optics, Quantum measurements, Quantum metrology, Quantum optics
Nearfield Vortex Dynamics of Supercell Bloch Modes
Research article | Metasurfaces | 2025-06-17 06:00 EDT
Xiaona Ye, Guangfeng Wang, Xiaoyang Duan, Ziwei Wang, Zengya Li, Tongtong Jia, Tingxin Li, Luqi Yuan, Bo Wang, and Xianfeng Chen
Densely arranged optical vortices are natural solutions of high-symmetry Bloch modes in photonic crystals. However, strict symmetry constraints limit the potential spatial configurations of nearfield vortices, restricting the control over light-matter interaction. Here, we demonstrate a nearfield vortex dynamic within a supercell photonic crystal. By introducing paired rotations of triangular structures, we achieve high-quality-factor Bloch mode transition from evanescent valley modes, to quasibound states in the continuum, frustrated modes, and quasivalleys. Each stage exhibits distinct nearfield vortex distributions, nonlinear overlap properties, and quality factors, revealing diverse physical behaviors for tailoring light-matter interaction. Notably, the asymmetric vortex configuration of frustrated modes enhances second harmonic generation, driven by an optimized nonlinear overlap factor. Our paired-rotation strategy offers a versatile design framework for creating supercell photonic crystals with unique nearfield vortex properties, presenting promising applications in lasing, nonlinear optics and optical forces.
Phys. Rev. Lett. 134, 243801 (2025)
Metasurfaces, Nanophotonics, Photonic crystals, Optical materials & elements
Ultrasensitive Higher-Order Exceptional Points via Non-Hermitian Zero-Index Materials
Research article | Classical optics | 2025-06-17 06:00 EDT
Dongyang Yan, Alexander S. Shalin, Yongxing Wang, Yun Lai, Yadong Xu, Zhi Hong Hang, Fang Cao, Lei Gao, and Jie Luo
Higher-order exceptional points (EPs) in optical structures enable ultrasensitive responses to perturbations. However, previous investigations on higher-order EPs have predominantly focused on coupled systems, leaving their fundamental physics in open scattering systems largely unexplored. Here, we harness wave interference to realize higher-order EPs in non-Hermitian zero-index materials connected to multiple open channels. Specifically, we show that a three-channel model can give rise to three interesting types of third-order EPs: lasing EP, reflecting EP, and absorbing EP. Notably, near the third-order absorbing EP, we show ultrasensitivity—a drastic change in output power in response to perturbations at the operating frequency—in a purely lossy system. These findings pave the way for achieving higher-order and even arbitrary-order EPs in open scattering systems, offering significant potential for advanced sensing applications.
Phys. Rev. Lett. 134, 243802 (2025)
Classical optics, Metamaterials, Exceptional points, Non-Hermitian systems
Image Rotation in Plasmas
Research article | Alfvén waves | 2025-06-17 06:00 EDT
Renaud Gueroult, Shreekrishna Tripathi, Jia Han, Patrick Pribyl, Jean-Marcel Rax, and Nathaniel J. Fisch
Because of the speed of light compared to material motion, the dragging of light is difficult to observe under laboratory conditions. Here, we report on the first observation of image rotation, i.e., a dragging by the medium of the wave’s transverse structure, of Alfv'en waves in plasmas. Exploiting the naturally slow group velocity of these waves, significant wave rotation is achieved for modest angular frequency. Control over the rotation of the wave’s structure is demonstrated through the plasma rotation imposed by biased electrodes. Remarkably, experimental results are well reproduced by light dragging theory derived for isotropic media, even if magnetized plasmas are anisotropic. In addition to offering new insights into the fundamental issue of angular momentum coupling between waves and media, these findings also open possibilities for new remote rotation sensing tools.
Phys. Rev. Lett. 134, 245101 (2025)
Alfvén waves, Angular momentum of light, Light propagation, transmission & absorption, Mechanical effects of light on material media, Plasma waves
Phase Diagram and Crystal Melting of Helium-4 in Two Dimensions
Research article | Entanglement entropy | 2025-06-17 06:00 EDT
David Linteau, Gabriel Pescia, Jannes Nys, Giuseppe Carleo, and Markus Holzmann
We study the zero-temperature phase diagram of two-dimensional helium-4 using neural quantum states. Our variational description allows us to address liquid and solid phases using the same functional form as well as exploring possible melting scenarios—for instance, via an intermediate hexatic phase. Notably, this is achieved by performing fixed pressure variational Monte Carlo calculations. Within the isobaric ensemble framework, we are able to clearly identify the first-order liquid-solid phase transition. We additionally compute the R'enyi-2 entanglement entropy across the liquid-solid phase transition and find a sharp decrease upon freezing. Calculations for larger systems follow the metastable liquid and solid branches in the transient region, while signatures of a hexatic order coexisting with a small condensate fraction are observed only for smaller systems as a finite-size effect.
Phys. Rev. Lett. 134, 246001 (2025)
Entanglement entropy, First order phase transitions, Liquid-solid phase transition, Helium-4 superfluids, Liquid crystals, Supersolids, Neural network simulations, Quantum Monte Carlo
Contribution of Water Molecules to the Electronic Dipole Moment across the Gold-Water Interface
Research article | Electronic structure | 2025-06-17 06:00 EDT
Soumya Ghosh, Chanbum Park, Harald Forbert, and Dominik Marx
Understanding metal-water interfaces is instrumental in developing electrochemical cells for energy conversion. In this Letter, we quantify the relative contribution of the metal surface and the solvent molecules to the electronic component of the interfacial dipole moment enabled by an implementation of partially occupied Wannier functions that allows us to treat interfacial water in contact with metallic surfaces. Our calculations show that the contribution of the solvent is of overriding importance and that it mostly originates from specific deformation of the water lone pairs very close to the metal surface.
Phys. Rev. Lett. 134, 246201 (2025)
Electronic structure, Surface & interfacial phenomena, Interfaces, Electric moment, Ab initio molecular dynamics, Wannier function methods
Kibble-Zurek Dynamics in the Anisotropic Ising Model of the Si(001) Surface
Research article | Quantum quench | 2025-06-17 06:00 EDT
G. Schaller, F. Queisser, S. P. Katoorani, C. Brand, C. Kohlfürst, M. R. Freeman, A. Hucht, P. Kratzer, B. Sothmann, M. Horn-von Hoegen, and R. Schützhold
As a simplified description of the nonequilibrium dynamics of buckled dimers on the Si(001) surface, we consider the anisotropic two-dimensional (2D) Ising model and study the freezing of spatial correlations during a cooling quench across the critical point. Depending on the cooling rate, we observe a crossover from one-dimensional (1D) to 2D behavior. For rapid cooling, we find effectively 1D behavior in the strongly coupled direction, for which we provide an exact analytic solution of the nonequilibrium dynamics. For slower cooling rates, we start to see 2D behavior where our numerical simulations show an approach to the usual Kibble–Zurek scaling in 2D.
Phys. Rev. Lett. 134, 246202 (2025)
Quantum quench, Surface instabilities, Surface reconstruction, Surfaces, Dynamic critical phenomena, Ising model, Master equation
Self-Powered Pure Spin Photocurrent in Bent CrSBr Monolayer
Research article | Photocurrent | 2025-06-17 06:00 EDT
Hongli Chen (陈红丽), Li Chen (陈立), Liyuan Chen (陈丽媛), Liyan Shang (商丽燕), Yawei Li (李亚巍), Liangqing Zhu (朱亮清), Junhao Chu (褚君浩), Shijing Gong (龚士静), and Zhigao Hu (胡志高)
With the booming development of two-dimensional (2D) flexible devices, flexure has attracted much attention as an emerging means to modulate device performances. Here, the magnetic-optical-electrical multifield coupling mechanism of spin photocurrent in bent CrSBr monolayer is investigated through first-principles calculations. The studies show that simple mechanical bending of monolayer CrSBr can successfully achieve the spatial separation of electrons and holes. The nonequilibrium process of photogenerated carriers in bent CrSBr modulates both the shift current density and the ballistic current density, thereby enabling the photovoltaic effect. Meanwhile, the built-in electric field generated by flexure drives the device toward more efficient self-powered behavior. Moreover, this self-powered polarization devices have excellent spin photovoltaic properties and high polarization sensitivity. The present Letter creates novel opportunities for 2D spintronics and opens new avenues for realizing self-powered polarization devices.
Phys. Rev. Lett. 134, 247001 (2025)
Photocurrent, Photovoltaic effect, Spin optoelectronics, 2-dimensional systems, First-principles calculations
Tracer and Current Fluctuations in Driven Diffusive Systems
Research article | Diffusion | 2025-06-17 06:00 EDT
Théotim Berlioz, Olivier Bénichou, and Aurélien Grabsch
Interacting particles diffusing in single file is a fundamental model of transport in narrow channels where particles cannot bypass each other. An important result has been obtained by Kollmann [Phys. Rev. Lett. 90, 180602 (2003)] for the mean square displacement of a tracer for any single-file model. It applies to any diffusive system, in particular the notable classes of colloidal systems and diffusive stochastic lattice gases. Since then, no analog result has been obtained in the important case where the particles are driven by an external field. Here, we fill this gap and determine the fluctuations and the skewness of the tracer’s position for any driven diffusive system. In addition, we also consider a variety of important observables such as the integrated current, the response of the system to the perturbation induced by the displacement of the tracer, and the correlations between several tracers. Furthermore, we also unveil fundamental relations underlying the out-of-equilibrium dynamics of driven diffusive systems. This work constitutes a step toward the determination of the full distribution of all these observables in driven one-dimensional systems of interacting particles.
Phys. Rev. Lett. 134, 247101 (2025)
Diffusion, Fluctuation theorems, Random walks, Exclusion processes
Soft Spots in Shell Buckling
Research article | Bifurcations | 2025-06-17 06:00 EDT
Sagy Lachmann and Shmuel M. Rubinstein
The energy landscape of thin shells under quasistatic loading represents their potential energy as a function of their shape. It has recently been shown for a narrow plate [S. Lachmann and S. M. Rubinstein, Phil. Trans. R. Soc. A 381, 2244 (2023)] that lateral probing can induce controlled trajectories in configuration space, providing an experimental method for measuring the energy landscape of a specific structure. In this Letter, we extend this method to explore the prebuckling behavior of poked cylindrical shells through the lens of the energy landscape. This approach offers an intuitive way to combine and synthesize the deformation responses from different probing locations into a cohesive description of the prebuckling dynamics, revealing the presence of local soft spots—regions where the structure is particularly susceptible to deformation. As the system is loaded, these soft spots appear as local minima in the energy barrier to buckling and are experimentally shown to act as attractors of nearby deformation. The energy landscape framework provides a general framework for understanding prebuckling dynamics, highlighting the role of spatially extended deformations and offering a new way of safely estimating shock sensitivity to buckling in real shells.
Phys. Rev. Lett. 134, 248201 (2025)
Bifurcations, Buckling, Classical mechanics, Material failure, Mechanical deformation, Dynamical systems, Mechanical testing
Hyperuniform Networks of Active Magnetic Robotic Spinners
Research article | Collective behavior | 2025-06-17 06:00 EDT
Jing Wang, Zihao Sun, Huaicheng Chen, Gao Wang, Duyu Chen, Guo Chen, Jianwei Shuai, Mingcheng Yang, Yang Jiao, and Liyu Liu
Disorder hyperuniform (DHU) systems possess a hidden long-range order manifested as the complete suppression of normalized large-scale density fluctuations like crystals, which endows them with many unique properties. Here, we demonstrate a new organization mechanism for achieving stable DHU structures in active-particle systems via investigating the self-assembly of robotic spinners with threefold symmetric magnetic binding sites up to a heretofore experimentally unattained system size, i.e., with $\sim 1,000$ robots. The spinners can self-organize into a wide spectrum of actively rotating three-coordinated network structures, among which a set of stable DHU networks robustly emerge. These DHU networks are topological transformations of a honeycomb network by continuously introducing the Stone-Wales defects, which are resulted from the competition between tunable magnetic binding and local twist due to active rotation of the robots. Our results reveal novel mechanisms for emergent DHU states in active systems and achieving novel DHU materials with desirable properties.
Phys. Rev. Lett. 134, 248301 (2025)
Collective behavior, Emergence of patterns, Exotic phases of matter, Living matter & active matter
Physical Review X
Local Magnetoelectric Effects as Predictors of Surface Magnetic Order
Research article | Magnetic order | 2025-06-17 06:00 EDT
Sophie F. Weber, Andrea Urru, and Nicola A. Spaldin
Magnetic order at antiferromagnet surfaces can be predicted from bulk symmetries via atomic-site magnetoelectric responses, revealing a method for predicting how magnetism changes at a material’s surface compared to its interior.
Phys. Rev. X 15, 021094 (2025)
Magnetic order, Surfaces, Density functional theory, Symmetries in condensed matter
arXiv
A Century of Bose-Einstein Condensation
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-18 20:00 EDT
Bose-Einstein Condensation is a phenomenon at the heart of many of the past century’s most intriguing and fundamental manifestations, such as superfluidity and superconductivity. It was discovered theoretically some 100 years ago, and unequivocally experimentally demonstrated in the context of weakly interacting gases 30 years ago. Since then, it has spawned a revolution in our understanding of fundamental phases of matter and collective quantum dynamics extending across all physical scales and energies, with unforeseen implications and the potential for envisaged quantum technological applications.
Quantum Gases (cond-mat.quant-gas), Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
Brief Comment to appear in Communications Physics (Nature)
Designing artificial zinc phosphate tribofilms with tailored mechanical properties by altering the chain length
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Sebastian Lellig, Subisha Balakumar, Peter Schweizer, Eva P. Mayer, Simon Evertz, Marcus Hans, Damian M. Holzapfel, Yin Du, Qing Zhou, Martin Dienwiebel, Johann Michler, Jochen M. Schneider
Zinc dialkyldithiophosphate (ZDDP), as the most prominent lubrication additive, forms tribofilms consisting primarily of zinc phosphate glasses containing sulfides. As sulfur is linked to environmental concerns, sulfur-free zinc phosphate coatings have been sputtered from a Zn3(PO4)2 target and investigated here. Based on the bridging to non-bridging oxygen ratio, determined by X-ray photoelectron spectroscopy (XPS), the as deposited coatings are classified as metaphosphates. As the annealing temperature is increased, the chain lengths are reduced, as witnessed by XPS data indicated by a loss of phosphorus and oxygen of the coating surface, likely due to hydrolysis with water from the atmosphere. Transmission electron microscopy energy-dispersive X-ray spectroscopy line scans show that the XPS-revealed composition change of the coating surface upon annealing occurs over the whole thickness of the coating. This alteration in composition and chain length reductions causes a rise in hardness, reduced Young’s modulus, and wear resistance. Therefore, the properties of the artificial zinc phosphate tribofilms can be tailored via a thermally stimulated composition change, causing an alternation in chain length from meta- to orthophosphate and thereby enabling the design of coatings with desired mechanical properties.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Manuscript: 19 pages, 6 figures. Supplementary information: 2 pages, 3 figures
The Hamiltonian mechanics of exotic particles
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Andrea Amoretti, Daniel K. Brattan, Luca Martinoia
We develop Hamiltonian mechanics on Aristotelian manifolds, which lack local boost symmetry and admit absolute time and space structures. We construct invariant phase space dynamics, define free Hamiltonians, and establish a generalized Liouville theorem. Conserved quantities are identified via lifted Killing vectors. Extending to kinetic theory, we show that the charge current and stress tensor reproduce ideal hydrodynamics at leading order, with the ideal gas law emerging universally. Our framework provides a geometric and dynamical foundation for systems where boost invariance is absent, with applications including but not limited to: condensed matter, active matter and optimization dynamics.
Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
52+20 pages, 2 figures
Room-Temperature Disorder-Driven Nonlinear Transport in Topological Materials
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Rhonald Burgos Atencia, Shanshan Liu, Kian Ping Loh, Dimitrie Culcer
Recent experiments have reported nonlinear signals in topological materials up to room temperature. Here we show that this response stems from extrinsic spin-orbit contributions to \textit{both} impurity and phonon scattering. While skew scattering dominates at low temperatures, the side jump contribution $ \propto \tau/\tau_\beta$ , where $ \tau$ , $ \tau_\beta$ are the momentum and skew scattering times respectively. Consequently side jump exhibits a weak temperature dependence and remains sizable at room temperature. Our results provide a roadmap for engineering nonlinear transport at ambient conditions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
7 pages, 5 figures
Spin Currents in Rashba Altermagnets: From Equilibrium to Nonlinear Regimes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
We investigate equilibrium (background), linear, and nonlinear spin currents in two-dimensional Rashba spin-orbit coupled altermagnet systems, using a modified spin current operator that includes anomalous velocity from non-zero Berry curvature. The background spin current, stemming from spin-orbit coupling and modulated by the altermagnet term ($ t_j$ ), exhibits in-plane polarization, increases linearly with Fermi energy ($ \epsilon_F$ ), and is enhanced by both the altermagnet ($ t_j$ ) and the Rashba parameter ($ \lambda$ ). Linear spin current is always transverse with out-of-plane polarization and can be viewed as Spin Hall current, primarily driven by band velocity, with $ t_j$ enabling a band-induced contribution (previously absent in simple Rashba systems ($ t_j=0$ )). This highlights altermagnet system as a promising source of spin Hall current generation. For linear spin Hall current, its band contribution’s magnitude increases linearly with $ \epsilon_F$ , while the magnitude of anomalous component saturates at higher $ \epsilon_F$ . Further, the magnitude of spin Hall current is enhanced by $ t_j$ but reduced by $ \lambda$ . Nonlinear spin currents feature both longitudinal and transverse components with in-plane polarization. Both the nonlinear longitudinal spin current from band velocity and the nonlinear transverse spin current from anomalous velocity initially decrease with $ \epsilon_F$ before saturating at higher $ \epsilon_F$ . Importantly, $ t_j$ reduces these currents while $ \lambda$ enhances them. Meanwhile, the nonlinear transverse current from band velocity increases and then saturates with $ \epsilon_F$ , enhanced by $ \lambda$ and showing non-monotonic variation with $ t_j$ . These findings highlight the tunability of spin current behavior through Rashba and altermagnet parameters, offering insights for spintronic applications.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 8 figures
Weyl semimetal engineering by symmetry control in NiTe$_2$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Marcos G. O. Junior, Augusto L. Araújo, Emmanuel V. C. Lopes, Tome M. Schmidt
In this work, we investigate the emergence of Weyl points in an inversion symmetry-breaking 1T-NiTe$ _2$ system. Through first-principles calculations based on the density functional theory combined with tight-binding methods, distinct number of Weyl crossings arise under an appropriate symmetry breaking. We identify three sets of Weyl points by breaking the inversion symmetry in NiTe$ _2$ , resulting in a total of 28 Weyl crossings. The first set comes from the Dirac semimetal, whereas the other two additional sets depend on the weight of the symmetry breaking. The topological characteristics of the Weyl semimetals have been investigated by computing the evolution of Wannier charge centers, providing their chiralities. Additionally, the bulk-boundary correspondence has been shown by computing the Fermi arcs. Our results provide a way for manipulating and creating distinct sets of Weyl points with appropriate external control, which can be valuable for applications in Weyltronics.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
AutoSAS: a new human-aside-the-loop paradigm for automated SAS fitting for high throughput and autonomous experimentation
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Duncan R. Sutherland, Rachel Ford, Yun Liu, Tyler B. Martin, Peter A. Beaucage
The advancement of artificial-intelligence driven autonomous experiments demands physics-based modeling and decision-making processes, not only to improve the accuracy of the experimental trajectory but also to increase trust by allowing transparent human-machine collaboration. High-quality structural characterization techniques (e.g., X-ray, neutron, or static light scattering) are a particularly relevant example of this need: they provide invaluable information but are challenging to analyze without expert oversight. Here, we introduce AutoSAS, a novel framework for human-aside-the-loop automated data classification. AutoSAS leverages human-defined candidate models, high-throughput combinatorial fitting, and information-theoretic model selection to generate both classification results and quantitative structural descriptors. We implement AutoSAS in an open-source package designed for use with the Autonomous Formulation Laboratory (AFL) for X-ray and neutron scattering-based optimization of multicomponent liquid formulations. In a first application, we leveraged a set of expert defined candidate models to classify, refine the structure, and track transformations in a model injectable drug carrier system. We evaluated four model selection methods and benchmarked them against an optimized machine learning classifier and the best approach was one that balanced quality of the fit and complexity of the model. AutoSAS not only corroborated the critical micelle concentration boundary identified in previous experiments but also discovered a second structural transition boundary not identified by the previous methods. These results demonstrate the potential of AutoSAS to enhance autonomous experimental workflows by providing robust, interpretable model selection, paving the way for more reliable and insightful structural characterization in complex formulations.
Soft Condensed Matter (cond-mat.soft)
20 pages, 6 figures
Atomic-scale insights on grain boundary segregation in a cathode battery material
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Inger-Emma Nylund, Elise R. Eilertsen, Constantinos A. Hatzoglou, Kaja Eggen Aune, Ruben Bjørge, Antonius T. J. van Helvoort, Ann Mari Svensson, Paraskevas Kontis
The grain boundary segregation of the Co-free pristine spinel LiNi0.5Mn1.5O4 cathode material has been studied by transmission electron microscopy and atom probe tomography. The segregation of Mn and the depletion of Ni at grain boundaries was observed by electron energy loss spectroscopy. These observations were also confirmed by atom probe tomography at other grain boundaries, which also revealed segregation of O and depletion of Li at grain boundaries. In addition, both methods revealed the occurrence of grain boundary segregation of Na, which is an impurity. Finally, segregation of O and Mn and a depletion of Li are also observed at dislocations. This observation has the potential to provide further support for the segregation behavior at the grain boundaries of this cathode material. These near-atomic-scale observations provide new insights that can be used to improve the synthesis and efficiency of Li-ion battery materials.
Materials Science (cond-mat.mtrl-sci)
5 figures, 1 supplementary figure
Evolution of charge correlations in the hole-doped kagome superconductor CsV$_{3-x}$Ti$_x$Sb$_5$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-18 20:00 EDT
Ganesh Pokharel, Canxun Zhang, Evgeny Redekop, Brenden R. Ortiz, Andrea N. Capa Salinas, Sarah Schwarz, Steven J. Gomez Alvarado, Suchismita Sarker, Andrea F. Young, Stephen D. Wilson
The interplay between superconductivity and charge correlations in the kagome metal CsV$ _3$ Sb$ _5$ can be tuned by external perturbations such as doping or pressure. Here we present a study of charge correlations and superconductivity upon hole doping via Ti substitution on the V kagome sites in CsV$ _{3-x}$ Ti$ _x$ Sb$ _5$ via synchrotron x-ray diffraction and scanning SQUID measurements. While the superconducting phase, as viewed via the vortex structure, remains conventional and unchanged across the phase diagram, the nature of charge correlations evolves as a function of hole-doping from the first superconducting dome into the second superconducting dome. For Ti doping in the first superconducting dome, competing $ 2\times 2 \times 2$ and $ 2\times 2 \times 4$ supercells form within the charge density wave state and are suppressed rapidly with carrier substitution. In the second superconducting dome, no charge correlations are detected. Comparing these results to those observed for CsV$ _3$ Sb$ _{5-x}$ Sn$ _x$ suggests important differences between hole doping via chemical substitution on the V and Sb sites, particularly in the disorder potential associated with each dopant.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 5 figures
Movable Dirac Points with Ferroelectrics: Kink States and Berry Curvature Dipoles
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Konstantin S. Denisov, Yuntian Liu, Igor Žutić
Two-dimensional (2D) Dirac states and Dirac points with linear dispersion are the hallmark of graphene, topological insulators, semimetals, and superconductors. Lowering a symmetry by the ferroelectric polarization opens the gap in Dirac points and introduces finite Berry curvature. Combining this with Dirac points detached from high symmetry points of the Brillouin zone offers additional ways to tailor topological properties. We explore this concept by studying topological phenomena emerging in 2D materials with movable Dirac points and broken out-of-plane mirror reflection. The resulting topological kink states and Berry curvature dipoles are changed by movable 2D Dirac points with experimental signatures in electrical conductance and second-harmonic nonlinear Hall conductivity. We identify materials platforms where our predictions can be realized and support that with the first-principles results for Cl$ _2$ Rh$ _2$ S$ _2$ -GeS junction.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Mechanically Interlocked Polymers in Dilute Solution under Shear and Extensional Flows: A Brownian Dynamics Study
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Mechanically interlocked polymers (MIPs) are a novel class of polymer structures in which the components are connected by mechanical bonds instead of covalent bonds. We measure the single-molecule rheological properties of polyrotaxanes, daisy chains, and polycatenanes under steady shear and steady uniaxial extension using coarse-grained Brownian dynamics simulations with hydrodynamic interactions. We obtain key rheological features, including tumbling dynamics, molecular extension, stress, and viscosity. By systematically varying structural features, we demonstrate how MIP topology governs flow response. Compared to linear polymers, all three MIP architectures exhibit enhanced tumbling in shear flow and lower normal stress differences in extensional flow. While polyrotaxanes show higher shear and extensional viscosities, polycatenanes and daisy chains have lower viscosities. In extensional flow, polyrotaxanes and polycatenanes extend earlier than linear polymers. We find that mechanical bonds suppress shear thinning and alter the coil-stretch transition observed in linear polymers. These effects arise from the mechanically bonded rings in MIPs, which expand the polymer profile in gradient direction and increase backbone stiffness due to ring-backbone repulsions. This study provides key insights into MIP flow properties, providing the foundation for their systematic development in engineering applications.
Soft Condensed Matter (cond-mat.soft)
17 pages, 8 figures, appendix
Resolving Andreev spin qubits in germanium-based Josephson junctions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Andreev spin qubits (ASQs) are a promising platform for quantum information processing which benefit from both the small footprint of semiconducting spin qubits and the long range connectivity of superconducting qubits. While state-of-the-art experiments have developed ASQs in InAs nanowires, these realizations are coherence-time limited by nuclear magnetic noise which cannot be removed by isotopic purification. In Ge-based Josephson junctions, which can be isotopically purified, Andreev states have been experimentally observed but spin-resolved Andreev states remain elusive. Here, we theoretically demonstrate that the geometry of the Josephson junction can limit the qubit frequency to values below typical experimental temperatures and render the ASQ effectively invisible. ASQs could be experimentally resolved by judiciously choosing the geometry of the junction and filling of the underlying Ge. Our comprehensive study of ASQ frequency on in situ and ex situ experimentally controllable parameters provides design guidance of Ge-based Josephson junctions and paves the way towards realization of high-coherence ASQs.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
9 pages, 9 figures
Disorder enhanced ferromagnetic polaron formation – and the test case of Europium Oxide
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-18 20:00 EDT
Tanmoy Mondal, Pinaki Majumdar
Europium Oxide (EuO), a low carrier density local moment ferromagnet, shows a wide variety of transport behaviour depending on preparative conditions. Some samples have a moderate resistivity with a modest peak near $ T_c$ while others show a huge peak in resistivity followed by insulating high temperature behaviour. These features have been known for decades and have been attributed to the presence of magnetic polarons in a disordered background. Actual attempts at a theory, however, reduce the problem either to a single trapped electron or to an averaged picture where the spatial physics of polarons is lost. The difficulty stems from having to handle electronic states in a magnetically fluctuating, structurally disordered background. Via an explicit real space calculation in two dimensions, we examine the interplay of disorder induced localisation and magnetic polaron formation and show how the resistivity trends in EuO could emerge from increasing impurity concentration. We estimate the polaron size in the disordered medium, establish the presence of a pseudogap near $ T_c$ , predict a crossover to incoherent, non Drude, optical response with growing disorder and temperature, and track the polaron `delocalisation’ with increasing magnetic field.
Strongly Correlated Electrons (cond-mat.str-el)
13 pages, 13 figures
Evolutionary chemical learning in dimerization networks
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Alexei V. Tkachenko, Bortolo Matteo Mognetti, Sergei Maslov
We present a novel framework for chemical learning based on Competitive Dimerization Networks (CDNs) - systems in which multiple molecular species, e.g. proteins or DNA/RNA oligomers, reversibly bind to form dimers. We show that these networks can be trained in vitro through directed evolution, enabling the implementation of complex learning tasks such as multiclass classification without digital hardware or explicit parameter tuning. Each molecular species functions analogously to a neuron, with binding affinities acting as tunable synaptic weights. A training protocol involving mutation, selection, and amplification of DNA-based components allows CDNs to robustly discriminate among noisy input patterns. The resulting classifiers exhibit strong output contrast and high mutual information between input and output, especially when guided by a contrast-enhancing loss function. Comparative analysis with in silico gradient descent training reveals closely correlated performance. These results establish CDNs as a promising platform for analog physical computation, bridging synthetic biology and machine learning, and advancing the development of adaptive, energy-efficient molecular computing systems.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Machine Learning (cs.LG), Adaptation and Self-Organizing Systems (nlin.AO), Data Analysis, Statistics and Probability (physics.data-an), Molecular Networks (q-bio.MN)
7 pages, 5 figures + SI
Structural Inhomogeneities and Suppressed Magneto-Structural Coupling in Mn-Substituted GeCo2O4
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Shivani Sharma, Pooja Jain, Benny Schundelmier, Chin-Wei Wang, Poonam Yadav, Adrienn Maria Szucs, Kaya Wei, N. P. Lalla, Theo Siegrist
A comprehensive study of Ge1-xMnxCo2O4 (GMCO) system was conducted using neutron powder diffraction (NPD), x-ray diffraction (XRD), Scanning electron microscopy, magnetometry, and heat capacity measurements. Comparative analysis with GeCo2O4 (GCO) highlights the influence of Mn substitution on the crystal and magnetic structure at low temperature. Surprisingly, phase separation is observed in GMCO with a targeted nominal composition of Ge0.5Mn0.5Co2O4. SEM/EDX analysis reveals that the sample predominantly consists of a Mn-rich primary phase with approximate stoichiometry Mn0.74Ge0.18Co2O4, along with a minor Ge-rich secondary phase of composition Ge0.91Mn0.19Co2O4. Although both GCO and GMCO crystallize in cubic symmetry at room temperature, a substantial difference in low-temperature structural properties has been observed. Magnetic and heat capacity data indicate ferrimagnetic ordering in the Mn-rich phase near TC = 108 K, while the Ge-rich phase exhibits antiferromagnetic order at TN = 22 K in GMCO. Analysis of heat capacity data reveals that the estimated magnetic entropy amounts to only 63% of the theoretical value expected in GMCO. A collinear ferrimagnetic arrangement is observed in the Mn rich phase below the magnetic ordering temperature, characterized by antiparallel spins of the Mn at A site and Co at B site along the c-direction. At 5 K, the refined magnetic moments are 2.31(3) for MnA and 1.82(3) uB for CoB in the Mn rich ferrimagnetic phase. The magnetic structure at 5 K in the Ge rich secondary phase is identical to the antiferromagnetic structure of the parent compound GeCo2O4. The refined value of the CoB moment in this phase at 5 K is 2.53(3) uB.
Materials Science (cond-mat.mtrl-sci)
19 pages,
The phenomenological renormalization group in neuronal models near criticality
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-06-18 20:00 EDT
Kaio F. R. Nascimento, Daniel M. Castro, Gustavo G. Cambrainha, Mauro Copelli
The phenomenological renormalization group (PRG) has been applied to the study of scaleinvariant phenomena in neuronal data, providing evidence for critical phenomena in the brain. However, it remains unclear how reliably these observed signatures indicate genuine critical behavior, as it is not well established how close to criticality a system must be for them to emerge. Here, we rely on neuronal models with known critical points to investigate under which conditions the PRG procedure yields consistent results. We discuss how the time-binning step of data preprocessing can crucially affect the final results, and propose a data-driven method to adapt the time bin in order to circumvent this issue. Under these conditions, the PRG method only detects scaling behavior in neuronal models within a very narrow range of the critical point, lending credence to the conclusions drawn from PRG results in experimental data.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech), Adaptation and Self-Organizing Systems (nlin.AO), Data Analysis, Statistics and Probability (physics.data-an)
8 pages, 4 figures
Emergence of Chern metal in a moiré Kondo lattice
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-18 20:00 EDT
Wenjin Zhao, Zui Tao, Yichi Zhang, Bowen Shen, Zhongdong Han, Patrick Knüppel, Yihang Zeng, Zhengchao Xia, Kenji Watanabe, Takashi Taniguchi, Jie Shan, Kin Fai Mak
A Chern metal is a two-dimensional metallic state of matter carrying chiral edge states. It can emerge as a doped Chern insulator, but theoretical studies have also predicted its emergence near a Kondo breakdown separating a metallic chiral spin liquid and a heavy Fermi liquid in a frustrated lattice. To date, the latter exotic scenario has not been realized. Here, we report the observation of a Chern metal at the onset of the magnetic Kondo breakdown in a frustrated moiré Kondo lattice–angle-aligned MoTe2/WSe2 bilayers. The state is compressible and is manifested by a nearly quantized Hall resistance but a finite longitudinal resistance that arises from a bad metallic bulk. The state also separates an itinerant and a heavy Fermi liquid and appears far away from the band inversion critical point of the material, thus ruling out its origin from simply doping a Chern insulator. We demonstrate the presence of a chiral edge state by nonlocal transport measurements and current-induced quantum anomalous Hall breakdown. Magnetic circular dichroism measurements further reveal a magnetization plateau for the Chern metal before a metamagnetic transition at the Kondo breakdown. Our results open an opportunity for moiré engineering of exotic quantum phases of matter through the close interplay between band topology and Kondo interactions.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Electronic nematic normal and superconducting state in electron-doped copper-oxide superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-18 20:00 EDT
J.Y. Shen, G.F. Chen, Y.C. Zhang, G.Y. Xi, J.Y. He, X.B. Cheng, J. Wu
The similarities and differences between hole- and electron-doped cuprates are central to studies of high-temperature superconductivity. While electronic nematicity is found to be pervasive in hole-doped cuprates, iron-based superconductors, and other unconventional superconductors, evidence for electronic nematicity in electron-doped cuprates remains elusive. Here, we discover that the normal state of electron-doped Sr0.9La0.1CuO2 (SLCO) is nematic by the angle-resolved resistivity (ARR) method and the uncovered ground state at zero temperature is also nematic when superconductivity is suppressed by an applied magnetic field. As we deliberately change the substrate from tetragonal KTaO3(001) (KTO) to orthorhombic GdScO3(110) (GSO), the nematic director of SLCO is pinned by the epitaxial strain but the nematic amplitude remains roughly the same, implying that the nematicity originates from electron-electron correlations. The nematicity is significantly enhanced by the presence of superconducting fluctuations and its amplitude increases appreciably as the effective doping level of SLCO is lowered from optimal to underdoped. Thus, electronic nematicity is intrinsic to high-temperature superconductors regardless of differences in the structural and electronic configurations corresponding to hole or electron doping.
Superconductivity (cond-mat.supr-con)
Asymmetric Diffusion of Chiral Skyrmions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
X. Zhang, C. Reichhardt, C.J.O. Reichhardt, Y. Zhou, Y. Xu, M. Mochizuki
Brownian dynamics of chiral matter in chiral environment may give rise to emergent phenomena that could not be observed in achiral environment. Here, we report the asymmetric diffusion of chiral skyrmions in two chambers separated by a chiral gate. The topology-determined Brownian gyromotion of skyrmions could lead to effective interactions between skyrmions and chamber walls with a sense of clockwise or counter-clockwise rotation. By fabricating a chiral gate separating two chambers, skyrmions could demonstrate asymmetric diffusion through the gate to approach a nonequilibrium state before reaching the thermal equilibrium. We focus on the asymmetric diffusion of skyrmions that depends on the gate chirality and opening width. Although the simulated diffusion of skyrmions is affected by the skyrmion density, which varies with time due to the diffusion and annihilation, the simulated outcomes are generally in line with simple theories assuming time-independent diffusion rates. Our results uncover asymmetric diffusive behaviors of chiral skyrmions interacting with chiral nanostructures, which will appeal to the wide audience interested in hard condensed matter systems, magnetism, active matter, and statistical physics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Statistical Mechanics (cond-mat.stat-mech)
6 pages, 3 figures
Misfit layered superconductor (PbSe)1.14(NbSe2)3 with possible layer-selective FFLO state
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-18 20:00 EDT
Yuki M. Itahashi, Yamato Nohara, Michiya Chazono, Hideki Matsuoka, Koichiro Arioka, Tetsuya Nomoto, Yoshimitsu Kohama, Youichi Yanase, Yoshihiro Iwasa, Kaya Kobayashi
Two-dimensional (2D) superconductors are known for their novel emergent phenomena, however, lack of experimental probes beyond resistivity has hindered further exploration of diverse superconducting states. Bulk 2D superconductors, with superconducting layers separated by non-superconducting layers, offer a unique opportunity to break this limit. Here, we synthesized a single crystal of misfit layered compound (PbSe)1.14(NbSe2)3, composed of alternately stacked tri-layer NbSe2 and non-superconducting block layers with incompatible unit cells. Due to its unique structure, 2D Ising superconductivity is maintained even in a bulk form. Resistivity and tunnel diode oscillator measurements reveal two distinct superconducting phases in magnetic field vs. temperature phase diagram. Combined with the theoretical analysis, the high-magnetic-field phase is identified as a layer-selective Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase, where Ising and finite-q superconductivity are mixed due to the tri-layer structure. Bulk 2D superconductors with misfit structure offer a novel opportunity for understanding of 2D superconductivity through bulk measurements and interlayer engineering.
Superconductivity (cond-mat.supr-con)
23 pages, 5 figures
Compositional fluctuations and polymorph selection in crystallization of model soft colloids
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Abhilasha Kumari, Gadha Ramesh, Debasish Koner, Rakesh S. Singh, Mantu Santra
Understanding polymorph selection in atomic and molecular systems and its control through thermodynamic conditions and external factors (such as seed characteristics) is fundamental to the design of targeted materials and holds great significance in materials sciences. In this work, using Monte Carlo simulations on the Gaussian Core Model and Hard-Core Yukawa colloidal systems, we investigated the control of polymorph selection and explored the underlying mechanisms by tuning thermodynamic parameters. We demonstrate that by carefully modifying the free energy landscape to render the globally stable face-centered cubic (FCC) phase metastable with respect to the body-centered cubic (BCC) phase, the polymorphic identity of particles transitions from FCC-dominated to BCC-dominated via an intermediate regime where both phases nucleate – either selectively or competitively – giving rise to a critical-like composition fluctuation of the growing solid-like cluster during the nucleation process. We further probed the critical solid-like cluster compositions, especially in the vicinity of the triple point where the three phases coexist, and observed an interpenetrating arrangement of FCC- and BCC-like particles rather than a commonly observed non-classical core-shell-like two-step nucleation scenario. In addition, we investigated the polymorph selection signatures encoded in local structural fluctuations of the metastable fluid using a machine learning approach based on structural descriptors derived from persistent homology, a topological data analysis method. We believe that the insights gained from this work have the potential to add to the ongoing efforts to control crystallization pathways to obtain the desired functional material.
Soft Condensed Matter (cond-mat.soft)
Resolving Phonons in Superconductor Bi2Sr2CaCu2O8+δ at Sub-Unit-Cell Resolution
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-18 20:00 EDT
Xiaowen Zhang, Jiade Li, Xiaoyue Gao, Ruochen Shi, Bo Han, Xiaomei Li, Jinlong Du, Jinsheng Wen, Genda Gu, Shichong Wang, Wentao Zhang, Peng Gao
The role of phonons in cuprates remains controversial, with their complex lattice structure complicating the investigation. Here, we identify phonon modes originating from charge reservoir and superconducting layers of Bi2Sr2CaCu2O8+{\delta} using sub-unit-cell resolved electron energy loss spectroscopy in a scanning transmission electron microscope. We reveal several phonon modes exhibiting layer-specific localization: ~78 meV in-plane modes localized in the CuO2 planes, ~42 meV hybrid (in-plane and out-of-plane) modes in the CuO2 planes, and ~38 meV hybrid modes in the BiO layers. We also observe a periodic modulation of phonon frequencies induced by the superstructure, spatially correlating with the superconducting gap variation. Our findings offer new insights into the electron-phonon coupling in cuprates, fostering deeper exploration of the microscopic linkage between lattice dynamics and superconductivity.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
Singular flat bands in three dimensions: Landau level spreading, quantum geometry, and Weyl reconstruction
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Takuto Kawakami, Yuji Igarashi, Mikito Koshino
We theoretically investigate three-dimensional singular flat band systems, focusing on their quantum geometric properties and response to external magnetic fields. As a representative example, we study the pyrochlore lattice, which hosts a pair of degenerate flat bands touching a dispersive band. We derive a three-orbital effective continuum model that captures the essential features near the band-touching point. Within this framework, we identify the point-like topological singularity on a planar manifold defined by the degenerate flat band eigenvectors. This singularity strongly influences the quantum geometry and results in a characteristic Landau level structure, where the levels spread over a finite energy range. We show that this structure reflects the underlying band reconstruction due to the orbital Zeeman effect, which lifts the flat band degeneracy and induces the Weyl-semimetal-like dispersion near the singularity. Our analysis reveals that the range of Landau level spreading is proportional to the quantum metric of each Zeeman-split band. We further demonstrate that adding a small dispersion via longer-range . Finally, we show that our approach extends naturally to systems with higher orbital angular momentum, indicating the robustness of these features in a broad class of three-dimensional flat band models.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
18 pages, 12 figures
Enhancing gate control and mitigating short channel effects in 20-50 nm channel length single-gate amorphous oxide Thin Film Transistors
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Chankeun Yoon, Yuchen Zhou, Ananth Dodabalapur
Field-effect transistors (FETs) with single gates are adversely affected by short channel effects such as drain-induced barrier lowering (DIBL) and increases in the magnitude of sub-threshold swing as the channel length is reduced. Dual-gate and gate-all-around geometries are often employed to improve gate control in very short channel length transistors. This can introduce significant process complexity to the device fabrication compared to single-gate transistors. It is shown in this paper that substantial reductions in short channel effects are possible in single-gate field-effect transistors with indium gallium zinc oxide semiconductor channels by modifying the design of the source and drain electrodes to possess an array of tapered tips which are designated as nanospike electrodes. 20-25 nm channel length FETs with nanospike electrodes have DIBL and other key metrics that are comparable to those in much larger (70-80 nm) channel length FETs with a conventional source/drain electrode design. These improvements stem from better gate control near the source and drain electrode tips due to the shape of these electrodes. These bottom gate FETs had a gate insulator consisting of 9 nm thick Al2O3 and independent Ni gates. This design approach is expected to be very helpful for a variety of semiconductor technologies being considered for back-end-of-line (BEOL) applications.
Materials Science (cond-mat.mtrl-sci)
Hetero-Orbital Two-Component Fractional Quantum Hall States in Bilayer Graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Ke Huang, Ajit C. Balram, Hailong Fu, Chengqi Guo, Kenji Watanabe, Takashi Taniguchi, Jainendra K. Jain, Jun Zhu
A two-dimensional electron system exposed to a strong magnetic field produces a plethora of strongly interacting fractional quantum Hall (FQH) states, the complex topological orders of which are revealed through exotic emergent particles, such as composite fermions, fractionally charged Abelian and non-Abelian anyons. Much insight has been gained by the study of multi-component FQH states, where spin and pseudospin indices of the electron contribute additional correlation. Traditional multi-component FQH states develop in situations where the components share the same orbital states and the resulting interactions are pseudospin independent; this homo-orbital nature was also crucial to their theoretical understanding. Here, we study “hetero-orbital” two-component FQH states, in which the orbital index is part of the pseudospin, rendering the multi-component interactions strongly SU(2) anisotropic in the pseudospin space. Such states, obtained in bilayer graphene at the isospin transition between N = 0 and N = 1 electron Landau levels, are markedly different from previous homo-orbital two-component FQH states. In particular, we observe strikingly different behaviors for the parallel-flux and reverse-flux composite fermion states, and an anomalously strong two-component 2/5 state over a wide range of magnetic field before it abruptly disappears at a high field. Our findings, combined with detailed theoretical calculations, reveal the surprising robustness of the hetero-orbital FQH effects, significantly enriching our understanding of FQH physics in this novel regime.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
22 pages, 12 figures including appendices
Breakdown of the Fluctuation-Dissipation Theorem in Kinetic Ising Models
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Parbati Saha, Sanjay Puri, Varsha Banerjee
Out-of-equilibrium dynamics, even in the simplest spin models, is still not well understood. The celebrated {\it fluctuation dissipation theorem} (FDT) does not hold for non-equilibrium systems. In this context, Cugliandolo and Kurchan introduced a generalized FDT which elucidates the non-equilibrium evolution as a composition of {\it time sectors} corresponding to different {\it effective temperatures}. We address these evaluations in the $ d=2$ long-range Ising model (LRIM), which surprisingly still has many lessons to teach. In particular, we investigate how interactions and conservation laws affect the non-equilibrium dynamics that is initiated by coarsening experiments. Quantifying the deviations from FDT in terms of $ T_{eff}$ , we find different aging scenarios for short- and long-range IM with non-conserved (Glauber) dynamics and conserved (Kawasaki) dynamics.
Statistical Mechanics (cond-mat.stat-mech)
24 pages, 5 figures
Isostructural electronic transition in MoS$_2$ probed by solid-state high harmonic generation spectroscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Bailey R. Nebgen, Victor Chang Lee, Jacob A. Spies, Randy M. Sterbentz, Craig P. Schwartz, Dean Smith, Diana Y. Qiu, Michael W. Zuerch
Studying materials under extreme pressure in diamond anvil cells (DACs) is key to discovering new states of matter, yet no method currently allows the direct measurement of the electronic structure in this environment. Solid-state high harmonic generation (sHHG) offers a new all-optical window into the electronic structure of materials. We demonstrate sHHG spectroscopy inside a DAC by probing $ 2H$ -MoS$ _2$ , up to 30 GPa, revealing a pressure-induced crossover of the lowest direct bandgap from the $ \textbf{K}$ -point to the $ \Gamma$ -point. This transition manifests as a sharp minimum in harmonic intensity and a 30° rotation of the sHHG polarization anisotropy, despite the absence of a structural phase change. First-principles simulations attribute these features to interference between competing excitation pathways at distinct points in the Brillouin zone. Our results establish sHHG as a sensitive probe of electronic transitions at high pressure, enabling access to quantum phenomena that evade detection by conventional techniques.
Materials Science (cond-mat.mtrl-sci)
Non-Hermitian topological electric circuits with projective symmetry
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Wenjie Zhang, Yuting Yang, Xiaopeng Shen, Liwei Shi, Zhi Hong Hang
Non-Hermitian topological insulators have attracted considerable attention due to their distinctive energy band characteristics and promising applications. Here, we systematically investigate non-Hermitian Möbius insulators and graphene-like topological semimetals from the projected symmetry and realize their corresponding topological phenomena in an electric circuit-based framework. By introducing a nonreciprocal hopping term consisting of negative impedance converters into a two-dimensional electric circuit, we establish an experimental platform that effectively demonstrates that introducing non-Hermitian terms significantly enhances the energy localization of topological edge states, which originate from the non-Hermitian skin effect. Furthermore, a thorough comparison of experimental measurements with numerical simulations validates the robustness and reliability of our electric circuit structure. This work not only reveals the physical properties of non-Hermitian topological materials but also provides valuable theoretical and experimental guidance for the implementation of topological circuits and the design of radiofrequency devices in the future.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
12 pages,7 figures
Controlling energy delivery with bistable nanostructures
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Andreas Ehrmann, Carl P. Goodrich
Countless biological processes are fueled by energy-rich molecules like ATP and GTP that supply energy with extreme efficiency. However, designing similar energy-delivery schemes from the bottom up, essential for the development of powered nanostructures and other {\it de novo} machinery, presents a significant challenge: how can an energy-rich structure be stable in solution yet still deliver this energy at precisely the right time? In this paper, we present a purely physical mechanism that solves this challenge, facilitating energy transfer akin to ATP hydrolysis, yet occurring between synthetic nanostructures without any biochemical interactions. This targeted energy delivery is achieved by exploiting a differentiable state-based model to balance the energy profiles that govern the structural transitions in the two nanostructures, creating a combined relaxation pathway with minimal barriers that facilitates energy delivery. We verify the effectiveness and robustness of this mechanism through Molecular Dynamics simulations, demonstrating that a bath of the high-energy structures can systematically and repeatedly drive the target structure out of equilibrium, enabling it to perform tasks. As the mechanism operates only through explicit physical forces without any biochemistry or internal state variables, our results present generic and far-reaching design principles, setting the stage for the next generation of synthetic nanomachines.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
9 pages, 4 figures
Noncentrosymmetric High-Temperature Superconductivity in doped $d^9$ Multiferroics
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-18 20:00 EDT
Multiferroics with $ d^9$ electronic configurations, such as $ SnCuO_2$ , $ PbCuO_2$ , and $ BiNiO_2$ , exhibit coexisting antiferromagnetic order and ferroelectricity. Motivated by the fundamental link between symmetry breaking, strong electron correlations, and unconventional superconductivity, we propose a materials design strategy targeting noncentrosymmetric high-temperature superconductors through chemical doping of engineered $ d^9$ multiferroics. This approach bridges two phenomena: (i) the coexistence of antiferromagnetism and ferroelectricity in correlated insulators, and (ii) the emergence of superconductivity in doped Mott/charge-transfer systems.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 6 figures
Random organization criticality with long-range hydrodynamic interactions
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Tristan Jocteur, Cesare Nardini, Eric Bertin, Romain Mari
Driven soft athermal systems may display a reversible-irreversible transition between an absorbing, arrested state and an active phase where a steady-state dynamics sets in. A paradigmatic example consists in cyclically sheared suspensions under stroboscopic observation, for which in absence of contacts during a shear cycle particle trajectories are reversible and the stroboscopic dynamics is frozen, while contacts lead to diffusive stroboscopic motion. The Random Organization Model (ROM), which is a minimal model of the transition, shows a transition which falls into the Conserved Directed Percolation (CDP) universality class. However, the ROM ignores hydrodynamic interactions between suspended particles, which make contacts a source of long-range mechanical noise that in turn can create new contacts. Here, we generalize the ROM to include long-range interactions decaying like inverse power laws of the distance. Critical properties continuously depend on the decay exponent when it is smaller than the space dimension. Upon increasing the interaction range, the transition turns convex (that is, with an order parameter exponent $ \beta > 1$ ), fluctuations turn from diverging to vanishing, and hyperuniformity at the transition disappears. We rationalize this critical behavior using a local mean-field model describing how particle contacts are created via mechanical noise, showing that diffusive motion induced by long-range interactions becomes dominant for slowly-decaying interactions.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
21 pages, 18 figures
Unraveling structural and magnetic information during growth of nanocrystalline SrFe12O19
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Cecilia Granados-Miralles, Matilde Saura-Múzquiz, Espen D. Bøjesen, Kirsten M. Ø. Jensen, Henrik L. Andersen, Mogens Christensen
The hydrothermal synthesis of magnetic strontium hexaferrite (SrFe12O19) nanocrystallites was followed in situ using synchrotron powder X-ray diffraction. For all the studied temperatures, the formation of SrFe12O19 happened through an intermediate crystalline phase, identified as the so-called six-line ferrihydrite (FeOOH). The presence of FeOOH has been overlooked in previous studies on hydrothermally synthesized SrFe12O19, despite the phase having a non-trivial influence on the magnetic properties of the final material. The chemical synthesis was successfully reproduced ex situ in a custom-designed batch-type reactor that resembles the experimental conditions of the in situ setup, while allowing larger quantities of material to be produced. The agreement in phase composition between the two studies reveals comparability between both experimental setups. Hexagonal platelet morphology is confirmed for SrFe12O19 combining Rietveld refinements of powder X-ray diffraction (PXRD) data with transmission electron microscopy (TEM). Room temperature magnetization curves were measured on the nanopowders prepared ex situ. The magnetic properties are discussed in the context of the influence of phase composition and crystallite size.
Materials Science (cond-mat.mtrl-sci)
J. Mater. Chem. C, 2016,4, 10903-10913
Doping dependence of the low temperature planar carrier density in overdoped YBa$_2$Cu$3$O${7-δ}$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-06-18 20:00 EDT
Rebecca Nicholls, Roemer Hinlopen, Jake Ayres, Tommy Kotte, Tobias Forster, Joonbum Park, Jeremy Sourd, Antony Carrington, Nigel Hussey
Whether a quantum critical point (QCP) demarcates the end of the pseudogap (PG) regime in hole-doped cuprates at a singular doping level $ p^\ast \approx 0.19$ remains an open question. A crucial part of this puzzle is how the carrier density predicted by electronic structure calculations is recovered for $ p > p^\ast$ . Here, we use magnetic fields up to 67 T to suppress superconductivity down to 50 K, allowing simultaneous measurement of the low-temperature Hall number $ n_{\mathrm{H}}$ and the in-plane resistivity anisotropy $ \rho_a/\rho_b$ in overdoped Y$ {1-x}$ Ca$ x$ Ba$ 2$ Cu$ 3$ O$ {7-\delta}$ single crystals. We confirm a previous finding [Badoux et al., Nature 531, 210 (2016)] that $ n{\mathrm{H}}$ (50 K) exhibits a sharp increase below $ p^\ast$ . Using the measured resistivity anisotropy, we extract the planar carrier density $ n{\mathrm{pl}} = n{\mathrm{H}} (\rho_a/\rho_b)^{-1}$ . The doping dependence of $ n{\mathrm{pl}}$ (50 K) reveals two key findings: (i) at optimal doping, $ n{\mathrm{pl}} \approx p$ , and (ii) the sharp rise in $ n_{\mathrm{H}}(p)$ is softened such that the full Fermi volume ($ n_{\mathrm{pl}} = 1 + p$ ) is only partially recovered at $ p^\ast$ . This result disfavors a conventional QCP scenario in which the PG endpoint corresponds to a reconstructed Fermi surface.
Superconductivity (cond-mat.supr-con)
Coupling Anisotropic Curvature and Nematic Order: Mechanisms of Membrane Shape Remodeling
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Yoav Ravid, Samo Penič, Luka Mesarec, Nir S. Gov, Veronika Kralj-Iglič, Aleš Iglič, Mitja Drab
This study theoretically investigates how anisotropic curved membrane components (CMCs) control vesicle morphology through curvature sensing, nematic alignment, topological defects, and volume constraints. By comparing arc-shaped and saddle-shaped CMCs, we identify a rich spectrum of steady-state phases. For fully CMC-covered vesicles, arc-shaped components drive a pearling-to-cylinder transition as nematic interactions strengthen, while on partially CMC-covered vesicles, the saddle-shaped CMCs stabilize necks between the convex regions of bare membrane. We map the steady-state shapes of vesicles partially covered by arc-like and saddle-shaped CMCs, exposing how different vesicle shapes depend on the interplay between nematic interactions and volume constraints, revealing several novel phases. By investigating the in-plane nematic field, we find that topological defects consistently localize to high-curvature regions, revealing how intrinsic and deviatoric curvature effects cooperate in membrane remodeling. These findings establish a unified framework for understanding how proteins and lipid domains with anisotropic intrinsic curvature shape cellular structures – from organelle morphogenesis to global cell shape.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
33 pages, 20 figures
Scaling and Universality at Noisy Quench Dynamical Quantum Phase Transitions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Saeid Ansari, R. Jafari, Alireza Akbari, Mehdi Abdi
Dynamical quantum phase transitions (DQPTs) have been studied in the extended XY model under both noiseless and noisy linear driven staggered field cases. In the time-independent staggered field case, the model exhibits a single critical point where the transition occurs from the spin-liquid phase to the antiferromagnetic phase. In the noiseless ramp case, unlike the transverse field XY model where DQPT always occurs for a quench crossing the single critical point, there is a critical sweep velocity above which the kinks corresponding to a DQPT are completely removed. Furthermore, in this case there are only two critical modes whose excitation probability is one-half. In the presence of a Gaussian white noise, we find that this critical sweep velocity decreases by increasing the noise strength, and scales linearly with the square of the noise intensity. A surprising result occurs when the noise intensity and sweep velocity are about the same order of magnitude, the number of critical modes is significantly increased, signalling a region with multiple critical modes. Furthermore, our findings indicate that the scaling of the dynamical free energy near the DQPTs time is the same for both noiseless and noisy ramp quenches.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
Dynamical Phase diagram of the Quantum Ising model with Cluster Interaction Under Noisy and Noiseless Driven field
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Sasan Kheiri, R. Jafari, S. Mahdavifar, Ehsan Nedaaee Oskoee, Alireza Akbari
In most lattice models, gap closing typically occurs at high-symmetry points in the Brillouin zone. In the transverse field Ising model with cluster interaction, besides the gap closing at high-symmetry points, the gap closing at the quantum phase transition between paramagnetic and cluster phases of the model can be moved by tuning the strength of the cluster interaction. We take advantage of this property to examine the nonequilibrium dynamics of the model in the framework of dynamical quantum phase transitions (DQPTs) after a noiseless and noisy ramp of the transverse magnetic field. The numerical results show that DQPTs always happen if the starting or ending point of the quench field is restricted between two critical points. In other ways, there is always critical sweep velocity above which DQPTs disappear. Our finding reveals that noise modifies drastically the dynamical phase diagram of the model. We find that the critical sweep velocity decreases by enhancing the noise intensity and scales linearly with the square of noise intensity for weak and strong noise. Moreover, the region with multi-critical modes induced in the dynamical phase diagram by noise. The sweep velocity under which the system enters the multi-critical modes (MCMs) region increases by enhancing the noise and scales linearly with the square of noise intensity
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
Reconfigurable three dimensional magnetic nanoarchitectures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Sabri Koraltan, Fabrizio Porrati, Robert Kraft, Sven Barth, Markus Weigand, Claas Abert, Dieter Suess, Michael Huth, Sebastian Wintz
Three-dimensional (3D) nanomagnetism is a rapidly developing field within magnetic materials research, where exploiting the third dimension unlocks opportunities for innovative applications in areas such as sensing, data storage, and neuromorphic computing. Among various fabrication techniques, focused electron beam-induced deposition (FEBID) offers high flexibility in creating complex 3D nanostructures with sub-100 nm resolution. A key challenge in the development of 3D nanomagnets is the ability to locally control the magnetic configuration, which is essential to achieve desired functionalities. In this work, the magnetization reversal mechanism of a three-dimensional nanoarchitecture fabricated using focused electron beam-induced deposition is investigated by combining direct observation via scanning transmission X-ray microscopy with finite element micromagnetic simulations. In particular, our investigation shows that the magnetization of the components of a three-dimensional Co3 Fe tetrapod can be reversed individually and sequentially. Finally, it is demonstrated that complete control and reconfigurability of the system can be achieved by tuning the direction of the applied magnetic field.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
10 pages, 6 figures
A Spintronic Battery with Reversible Modulation of Spin Polarization through Li Charge/Discharge: A First Principles Computational Modelling Case Study for an Antiperovskite System
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Sk Mujaffer Hossain, Vinila Bedekara, Priyanka Yadavb, Ram Janay Chudhary, Satishchandra Ogale
A key notion defining the progress of the emergent fields of modern electronics, renewable energy, and smart systems is charge storage, which is primarily embodied in various battery chemistries and systems. In addition to the charge property, the electron also has the spin property, which is exploited in the field of spintronics to access novel magnetically controlled device actions that are not accessible to conventional electronics. An interesting question is whether the two can be fruitfully integrated into a single device concept to expand the horizon of device design and applications. Herein, we present a combined experimental and theoretical study of virgin and lithiated conducting intermetallic anti-perovskite with nominal stoichiometry represented as LixFe3SnC (x = 1, 2, 3, 4) to establish the principle of reversible and concurrent charge and spin polarization storage that can be aptly christened as Iono-Spintronics, representing a notion of a spintronic battery. The experimental results, however, showed that lithiation turns the system into a biphasic state comprised of tin-lithium alloy (due to the high affinity of Sn for Li) along with lithiated Fe3C. The process exhibits multiple cyclability (rechargeability).
Materials Science (cond-mat.mtrl-sci)
Cyclically sheared colloidal gels: structural change and delayed failure time
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Himangsu Bhaumik, James E. Hallett, Tanniemola B. Liverpool, Robert L. Jack, C. Patrick Royall
We present experiments and simulations on cyclically sheared colloidal gels, and probe their behaviour on several different length scales. The shearing induces structural changes in the experimental gel, changing particles’ neighborhoods and reorganizing the mesoscopic pores. These results are mirrored in computer simulations of a model gel-former, which show how the material evolves down the energy landscape under shearing, for small strains. By systematic variation of simulation parameters, we characterise the structural and mechanical changes that take place under shear, including both yielding and strain-hardening. We simulate creeping flow under constant shear stress, for gels that were previously subject to cyclic shear, showing that strain-hardening also increases gel stability. This response depends on the orientation of the applied shear stress, revealing that the cyclic shear imprints anisotropic structural features into the gel.
Soft Condensed Matter (cond-mat.soft)
12 pages
Thermodynamic control of non-equilibrium systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
We study the thermodynamic cost associated with driving systems between different non-equilibrium steady states. In particular, we combine a linear-response framework for non-equilibrium Markov systems with Lagrangian techniques to minimize the dissipation associated with driving processes. We then apply our framework to a simple toy model. Our results show several remarkable properties for the optimal protocol, such as diverging parameters and finite entropy production in the slow-driving limit.
Statistical Mechanics (cond-mat.stat-mech)
6 pages, 5 figures, 9 page appendix
Polarization switching on the open surfaces of the wurtzite ferroelectric nitrides: ferroelectric subsystems and electrochemical reactivity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Yongtao Liu, Anton V. Ievlev, Eugene A. Eliseev, Nana Sun, Kazuki Okamoto, Hiroshi Funakubo, Anna N. Morozovska, Sergei Kalinin
Binary ferroelectric nitrides are promising materials for information technologies and power electronics. However, polarization switching in these materials is highly unusual. From the structural perspective, polarization reversal is associated with the change of the effective polarity at the surfaces and interfaces from N-to-M terminated, suggesting strong coupling between ferroelectric and chemical phenomena. Phenomenologically, macroscopic studies demonstrate the presence of complex time dependent phenomena including wake-up. Here, we explore the polarization switching using the multidimensional high-resolution piezoresponse force microscopy (PFM) and spectroscopy, detecting both the evolution of induced ferroelectric domain, electromechanical response, and surface deformation during first-order reversal curve measurements. We demonstrate the presence of two weakly coupled ferroelectric subsystems and the bias-induced electrochemical reactivity. The observed behaviors are very similar to the recent studies of other wurtzite system but additionally include electrochemical reactivity, suggesting the universality of these behaviors for the wurtzite binary ferroelectrics. These studies suggest potential of high-resolution multimodal PFM spectroscopies to resolve complex coupled polarization dynamics in materials. Furthermore, these PFM based studies are fully consistent with the recent electron microscopy observations of the shark-teeth like ferroelectric domains in nitrides. Hence, we believe that these studies establish the universal phenomenological picture of polarization switching in binary wurtzite.
Materials Science (cond-mat.mtrl-sci)
22 pages; 7 figures
Signature of current-induced nuclear spin polarization in (Bi${1-x}$Sb${x}$)$_2$Te$_3$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Sofie Kölling, İnanç Adagideli, Alexander Brinkman
In systems with spin-momentum locking, such as the surface states of three-dimensional topological insulators, a charge current is spin-polarized and spin-flip interactions between electron and nuclear spins can transfer this polarization to the nuclear spin system. When a nonzero bias voltage is applied, the nuclear polarization reaches a steady-state value. This polarization emerges as an effective in-plane magnetic field acting on electrons, called the Overhauser field, which causes an offset in-plane magnetoresistance perpendicular to the current, visible in experiments. The in-plane offset is measured in the three-dimensional topological insulator \bsttight, and the magnitude of the magnetic field offset is compared to the Overhauser field. We attribute the observed magnetic field offset to current-induced nuclear polarization in \bsttight, which forms an important step towards experimentally realizing an entropic inductor.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
7 + 8 pages, 3 + 4 figures
From Attraction to Repulsion: Emergent Interactions in Harmonically Coupled Active Binary System
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Ritwick Sarkar, Sreya Chatterjee, Urna Basu
We investigate the emergent interactions between two active Brownian particles coupled by an attractive harmonic potential and in contact with a thermal reservoir. By analyzing the stationary distribution of their separation, we demonstrate that the effective interaction can be either attractive or repulsive, depending on the interplay between activity, coupling strength, and temperature. Notably, we find that an effective short-range repulsion emerges in the strong and moderate-coupling regimes, when the temperature is below some threshold value, which we characterize analytically. In the strong-coupling regime, the repulsion emerges due to the difference in the self-propulsion speeds of the particles. We also compute the short-time position distribution of the centroid of the coupled particles, which shows strongly non-Gaussian fluctuations at low temperatures.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
23 pages, 10 figures
Multisubband Plasmons in InAs/GaSb Broken Gap Quantum Well
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Wojciech Julian Pasek, Soufiane Hajji, Oussama Tata, Laurent Cerutti, Fernando Gonzalez-posada Flores, Simon Hurand, Abdelouahed El Fatimy, Thierry Taliercio
Multi-subband plasmon (MSP) modes in heavily doped InAs/GaSb broken-gap quantum wells grown via molecular beam epitaxy (MBE) are investigated. An $ 8$ -band $ \vec{k} \cdot \vec{p}$ semiclassical model accurately predicts ellipsometric spectra, reflecting strong subband hybridization and non-parabolicity. In contrast, single-band plasmon models show qualitative discrepancies with experiment, even with adjusted effective masses. These findings highlight the potential of broken-gap wells for quantum technologies leveraging interband coupling and wavefunction hybridization.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
In situ growth of a type-II ZnO/ZnS heterostructure:From stability to band-offset
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
P. R. A de Oliveira, I. Coelho, G. Felix, P. Venezuela, F. Stavale
We have successfully obtained a ZnO/ZnS heterostructure by heating a ZnS(001) single crystal in a controlled impurities-free oxygen atmosphere. Combining X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM), we explore the stability, electronic structure, and morphology of that interface. Our XPS measurements reveal a binding energy shift of the core-level peaks, indicating a band-bending effect due to the formation of a hybrid ZnO/ZnS interface. In addition, AFM measurements show that exposure of ZnS single-crystal to an oxygen atmosphere leads to the formation of ZnO/ZnS-like islands. Interestingly, our band-offset estimation suggest a type-II heterostructure arrangement with suitable electronic edges positions that turn ZnO/ZnS heterostructure a promising platform for catalytic applications, particularly hydrogen and oxygen evolution reactions.
Materials Science (cond-mat.mtrl-sci)
5 Figures. Supporting information available under request
Absorbance marker: Detection of quantum geometry and spread of Wannier function in disordered 2D semiconductors
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-18 20:00 EDT
Luis F. Cárdenas-Castillo, Shuai Zhang, Fernando L. Freire Jr., Wei Chen
The optical absorbance of 2D semiconductors is generalized to individual lattice sites through the topological marker formalism, yielding an absorbance marker. This marker allows to investigate the atomic scale variation of absorbance caused by impurities, thereby quantifies the influence of disorder on the quantum geometry and the spread of Wannier functions of valence band states. Applying this marker to transition metal dichalcogenides reveals a very localized suppression of absorbance caused by potential impurities, rendering a reduction of absorbance in the macroscopic scale proportional to the impurity density, in good agreement with the experimental results of plasma-treated WS$ _{2}$ .
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 2 figures
Thermal Conductivity Of Monolayer Hexagonal Boron Nitride: Four-Phonon Scattering And Quantum Sampling Effects
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
José Pedro Alvarinhas Batista, Matthieu J. Verstraete, Aloïs Castellano
Monolayer hexagonal boron nitride is a prototypical planar 2-dimensional system material and has been the subject of many investigations of its exceptional vibrational, spectroscopic and transport properties. The lattice thermal conductivity remains quite uncertain, with theoretical and experimental reports varying between 218 and 1060 Wm-1K-1. It has a strong temperature evolution and is sensitive to strain effects and isotope concentrations. While the impact of isotope scattering has been widely studied and is well understood, nuclear quantum effects and 4-phonon scattering have so far been neglected. Monolayer hexagonal boron nitride is composed of light elements, and further has its 3-phonon scattering phase space restricted by mirror plane symmetry, so these effects may be of similar order as isotope scattering, and would lead to a completely different understanding of the fundamental processes limiting the lattice thermal conductivity for this system. In this work, we use both classical and path-integral molecular dynamics, in conjunction with the Temperature Dependent Effective Potential method, to compute temperature-dependent renormalized phonons including isotope scattering, 3-phonon scattering, 4-phonon scattering and nuclear quantum effects. We show the impact of the latter two on the lattice thermal conductivity for a large temperature range, as well as their impact on the phonon lifetimes. Overall, our work provides a robust framework for calculations of the lattice thermal conductivity in solids, providing quantitative improvements and physical understanding that help explain the variety of results found in the literature.
Materials Science (cond-mat.mtrl-sci)
Coarsening Kinetics in Active Model B+: Macroscale and Microscale Phase Separation
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Pradeep Kumar Yadav, Shradha Mishra, Sanjay Puri
We perform a comprehensive numerical investigation of the coarsening kinetics of active Brownian particles modeled by the {\it Active Model B+} (AMB+). This model was introduced by Tjhung et al. [Phys. Rev. X {\bf 8}, 031080 (2018)] and is a generalization of Model B for a conserved order parameter, with two additional activity terms. These terms correspond to rotation-free current (of strength $ \lambda$ ) and rotational current (of strength $ \xi$ ). We find that the presence of rotational current $ (\xi \neq 0)$ significantly affects growth kinetics. Depending on the parameter values, AMB+ exhibits either {\it macroscale phase separation} (MPS) or {\it microscale phase separation} ($ \mu$ PS). We present detailed results for the kinetics of MPS and $ \mu$ PS in AMB+ with critical composition.
Soft Condensed Matter (cond-mat.soft)
Super-diffusive sub-picosecond extraction of hot carriers in black phosphorous
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Katsumasa Yoshioka, Taro Wakamura, Takuya Okamoto, Norio Kumada
Harvesting hot carriers before they lose energy to the lattice is a critical route toward surpassing the conventional thermodynamic limit in optical-to-electrical (O-E) conversion. However, photocurrent from such hot carriers has remained challenging to directly detect because they equilibrate on picosecond timescales, outpacing conventional electronic measurement. Here, by employing terahertz electronics with sub-picosecond temporal resolution, we directly monitor hot-carrier-driven O-E conversion in black phosphorus (BP). Photoexcitation near the metal contact under zero source-drain bias generates an ultrafast photocurrent with a decay time of ~400 fs, orders of magnitude faster than the typical sub-nanosecond energy relaxation in BP, demonstrating a measured 3 dB bandwidth of 260 GHz with an intrinsic limit of ~600 GHz. Notably, this photocurrent flows via energetic holes toward the contact electrode, regardless of the equilibrium carrier type, revealing a super-diffusive hot-carrier extraction mechanism. Furthermore, we show that the ultrafast hot-carrier contribution can coexist with the much slower cold-carrier contribution based on the photovoltaic effect, demonstrating that hot carriers can be harvested without discarding lower-energy carriers. These findings highlight the potential of sub-picosecond hot-carrier extraction to expand the O-E conversion bandwidth without sacrificing efficiency, bridging fundamental hot-carrier physics with ultrahigh-speed technological applications.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
22 pages, 4 figures, Supplementary information
Translation symmetry restoration in integrable systems: the noninteracting case
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Molly Gibbins, Adam Smith, Bruno Bertini
The study of symmetry restoration has recently emerged as a fruitful means to extract high-level information on the relaxation of quantum many-body systems. This revealed, for instance, the surprising ‘quantum Mpemba effect’ that occurs when a symmetry is restored more rapidly when the initial configuration is less symmetric. While the restoration of internal symmetries has been investigated intensively, however, the one of spatial symmetries has only been considered recently in the context of random unitary circuits. Here we present a complementary study of translation symmetry restoration in integrable systems. Specifically, we consider non-interacting spinless fermions on the lattice prepared in non-equilibrium states invariant only under $ \nu>1$ lattice shifts and follow the restoration of one-site shift invariance. We do so by measuring the Frobenius distance between the state on a subsystem, and its symmetrised counterpart. We compute the latter exactly, using standard Gaussian methods, and formulate a quasiparticle picture – involving multiplets of $ \nu$ correlated quasiparticles – to describe analytically its asymptotic behaviour. We show that, differently from random unitary circuits where symmetry restoration occurs abruptly for times proportional to the subsystem size, here symmetry is restored smoothly and over timescales of the order of the subsystem size squared. Interestingly, we also show that, in contrast to the case of continuous internal symmetries, the quasiparticle picture does not provide a quantitative description of discrete translation symmetry restoration and that the latter process goes beyond the hydrodynamic description. Our results can directly be extended to higher dimensions.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
10 pages, 5 figures
Hydrodynamic theory of wetting by active particles
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Noah Grodzinski, Robert L. Jack, Michael E. Cates
The accumulation of self-propelled particles on repulsive barriers is a widely observed feature in active matter. Despite being implicated in a broad range of biological processes, from biofilm formation to cytoskeletal movement, wetting of surfaces by active particles remains poorly understood. In this work, we study this active wetting by considering a model comprising an active lattice gas, interacting with a permeable barrier under periodic boundary conditions, for which an exact hydrodynamic description is possible. Our model eliminates dynamical noise while retaining microscopic fidelity, enabling a precise characterisation of steady-states and their transitions. We demonstrate that the accumulation of active particles is remarkably similar to equilibrium wetting, and that active wetting transitions retain all the salient characteristics of equilibrium critical wetting - despite fundamental differences in underlying microscopic dynamics. Additionally, we uncover a ratchet mechanism on permeable barriers in active systems, and demonstrate that this gives rise to steady-state currents and a novel transition pathway in active wetting. Our results provide an intrinsically nonequilibrium framework in which to study active wetting, and precisely demonstrate the connection to equilibrium wetting - while clarifying how differences in microscopic dynamics give rise to novel macroscopic behaviour.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
23 pages, 10 figures
250 Magnetic Tunnel Junctions-Based Probabilistic Ising Machine
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Shuhan Yang, Andrea Grimaldi, Youwei Bao, Eleonora Raimondo, Jia Si, Giovanni Finocchio, Hyunsoo Yang
In combinatorial optimization, probabilistic Ising machines (PIMs) have gained significant attention for their acceleration of Monte Carlo sampling with the potential to reduce time-to-solution in finding approximate ground states. However, to be viable in real applications, further improvements in scalability and energy efficiency are necessary. One of the promising paths toward achieving this objective is the development of a co-design approach combining different technology layers including device, circuits and algorithms. Here, we experimentally demonstrate a fully connected PIM architecture based on 250 spin-transfer torque magnetic tunnel junctions (STT-MTJs), interfaced with an FPGA. Our computing approach integrates STT-MTJ-based tunable true random number generators with advanced annealing techniques, enabling the solution of problems with any topology and size. For sparsely connected graphs, the massive parallel architecture of our PIM enables a cluster parallel update method that overcomes the serial limitations of Gibbs sampling, leading to a 10 times acceleration without hardware changes. Furthermore, we prove experimentally that the simulated quantum annealing boosts solution quality 20 times over conventional simulated annealing while also increasing robustness to MTJ variability. Short pulse switching measurements indicate that STT-MTJ-based PIMs can potentially be 10 times faster and 10 times more energy-efficient than graphic processing units, which paves the way for future large-scale, high-performance, and energy-efficient unconventional computing hardware implementations.
Materials Science (cond-mat.mtrl-sci)
5 figures
Uncertainty in AI-driven Monte Carlo simulations
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-06-18 20:00 EDT
Dimitrios Tzivrailis, Alberto Rosso, Eiji Kawasaki
In the study of complex systems, evaluating physical observables often requires sampling representative configurations via Monte Carlo techniques. These methods rely on repeated evaluations of the system’s energy and force fields, which can become computationally expensive, particularly in the presence of long-range interactions. To accelerate these simulations, deep learning models are increasingly employed as surrogate functions to approximate the energy landscape or force fields. However, such models introduce epistemic uncertainty in their predictions, which may propagate through the sampling process and affect the system’s macroscopic behavior. In this work, we present the Penalty Ensemble Method (PEM) to quantify epistemic uncertainty and mitigate its impact on Monte Carlo sampling. Our approach introduces an uncertainty-aware modification of the Metropolis acceptance rule, which increases the rejection probability in regions of high uncertainty, thereby enhancing the reliability of the simulation outcomes.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech)
Anomalous diffusion for mass transport phenomena II: Subdiffusion in polydimethylsiloxane (PDMS)
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Nathaniel G. Hermann, Dmitry A. Markov, M. Shane Hutson
Polydimethylsiloxane (PDMS) is a glassy polymer widely used in biomedical engineering, namely in microfluidics applications. However, PDMS is known to interact with hydrophobic chemicals. This interaction is exacerbated at the scale of microfluidics, making careful modeling of in-device concentrations vital for PDMS-based microfluidic devices. While it has been previously reported that many chemicals diffuse through PDMS, here we report that diffusion in PDMS is anomalous, i.e. characterized by nonlinear, subdiffusive mean-squared displacements (MSD). We show that this anomalous diffusion can be modeled in the framework of stretched-time fractional diffusion, and report the transport parameters for a set of fluorescent tracer dyes. Depending on the device geometry and protocol, this anomalous behavior may have a significant impact, specifically in regards to cross-talk between microfluidic channels.
Soft Condensed Matter (cond-mat.soft)
20 pages, 7 figures (including supplementary material)
Mutual effect of charge- and number-density correlations in ionic liquids and concentrated electrolytes
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Correlation functions in concentrated ionic systems are studied within the mesoscopic theory at the level of the Gaussian approximation. The previously neglected fluctuation contribution to the inverse charge-charge correlation function is taken into account to verify the accuracy of the previous results. We calculate the correlation lengths and the amplitudes and show that the fluctuation contribution does not lead to significant changes of the results. We also derive necessary conditions for the presence of both, the oscillatory and the monotonic decays of the charge-charge correlations that must be satisfied by the noncoulombic contributions to the inverse charge-charge correlation function. At the level of the Gaussian approximation, these conditions are not satisfied. Extension of the theory beyond the Gaussian approximation is necessary to verify whether the asymptotic decay of the charge-charge correlations is monotonous or oscillatory, as suggested by the surface force apparatus or by the SAXS experiments, respectively.
Soft Condensed Matter (cond-mat.soft)
14 pages, 5 figures
Predicting the response of structurally altered and asymmetrical networks
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-06-18 20:00 EDT
We investigate how the response of coupled dynamical systems is modified due to a structural alteration of the interaction. The majority of the literature focuses on additive perturbations and symmetrical interaction networks. Here, we consider the challenging problem of multiplicative perturbations and asymmetrical interaction coupling. We introduce a framework to approximate the averaged response at each network node for general structural perturbations, including non-normal and asymmetrical ones. Our findings indicate that both the asymmetry and non-normality of the structural perturbation impact the global and local responses at different orders in time. We propose a set of matrices to identify the nodes whose response is affected the most by the structural alteration.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Dynamical Systems (math.DS), Adaptation and Self-Organizing Systems (nlin.AO)
6 pages, 5 figures
Replica RISM molecular solvation theory for electric double layer in nanoporous materials
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Applications of 3D-RISM-KH molecular solvation theory range from solvation energy of small molecules to phase behavior of polymers and biomolecules. It predicts the molecular mechanisms of chemical and biomolecular systems. Replica RISM-KH-VM molecular solvation theory predicts and explains the structure, thermodynamics, and electrochemistry of electrolyte solutions sorbed in a nanoporous material. It was tested on nanoporous carbon supercapacitors with aqueous electrolyte and nanoporous electrosorption cells. The mechanisms in these systems are steered by the electric double layer potential drop across the Stern layer at the nanopores surface and the Gouy-Chapman layer averaged over the nanoporous material, the osmotic term due to the ionic concentrations difference in the two nanoporous electrodes and in the electrolyte solution outside, and the solvation chemical potentials of sorbed ions averaged over the nanoporous material. The latter strongly depends on chemical specificity of ions, solvent, surface functional groups, and steric effects for solvated ions confined in nanopores.
Soft Condensed Matter (cond-mat.soft)
20 pages, 11 figures
Liquid-gas state regularities as a manifestation of global isomorphism with the Ising model
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
L. A. Bulavin, V. L. Kulinskii, A. M. Katts, A. M. Maslechko
Liquid-gas equilibrium is considered using the global isomorphism with the Ising-like (lattice gas) model. Such an approach assumes the existence of the order parameter in terms of which the symmetry of binodal is restored not only in the vicinity of the critical point (critical isomorphism) but also globally in the whole coexistence region. We show how the empirical law of the rectilinear density diameter of the liquid-gas binodal allows us to derive a rather simple form of the isomorphism transformation between the fluid and lattice gas model of Ising-type. The relations for critical parameters which follow from such isomorphism are tested on a variety of fluid systems, both real and model ones. Moreover, we consider the phase equilibrium in polymer solutions and the Flory $ \theta$ -point as the extreme state of such equilibrium within our approach. The most crucial testing in 2D case is using the Onsager exact solution of the Ising model, and we represent the results of our approach to the calculation of critical point parameters of monolayers for noble gases and the surface tension.
Soft Condensed Matter (cond-mat.soft)
13 pages, 5 figures, 4 tables
Towards construction of microscopic model for smart coating of a solid surface
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
The density functional approach for classical associating fluids is used to explore the wetting phase diagrams for model systems consisting of water and graphite-like solid surfaces chemically modified by a small amount of grafted chain molecules. The water-like fluid model is adopted from the work of Clark et al. [Mol. Phys., 104, 3561 (2006)]. It very well describes the bulk water vapor-liquid coexistence. Each chain molecule consists of tangentially bonded hard sphere segments. We focus on the investigation of the growth of water film on such complex substrates and exploration of the wetting behavior. For grafted monomers, the prewetting phase diagrams are similar to the diagrams for water on a non-modified solid surface. However, for grafted trimers and pentamers, a physically much richer behavior is observed and analyzed. Trends of the behavior of the wetting temperature and the prewetting critical temperature on the grafting density and water-segments attraction are discussed in detail.
Soft Condensed Matter (cond-mat.soft)
17 pages, 8 figures
High yield, low disorder Si/SiGe heterostructures for spin qubit devices manufactured in a BiCMOS pilot line
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Alberto Mistroni, Marco Lisker, Yuji Yamamoto, Wei-Chen Wen, Fabian Fidorra, Henriette Tetzner, Laura K. Diebel, Lino Visser, Spandan Anupam, Vincent Mourik, Lars R. Schreiber, Hendrik Bluhm, Dominique Bougeard, Marvin H. Zoellner, Giovanni Capellini, Felix Reichmann
The prospect of achieving fault-tolerant quantum computing with semiconductor spin qubits in Si/SiGe heterostructures relies on the integration of a large number of identical devices, a feat achievable through a scalable (Bi)CMOS manufacturing approach. To this end, both the gate stack and the Si/SiGe heterostructure must be of high quality, exhibiting uniformity across the wafer and consistent performance across multiple fabrication runs. Here, we report a comprehensive investigation of Si/SiGe heterostructures and gate stacks, fabricated in an industry-standard 200 mm BiCMOS pilot line. We evaluate the homogeneity and reproducibility by probing the properties of the two-dimensional electron gas (2DEG) in the shallow silicon quantum well through magnetotransport characterization of Hall bar-shaped field-effect transistors at 1.5 K. Across all the probed wafers, we observe minimal variation of the 2DEG properties, with an average maximum mobility of $ (4.25\pm0.17)\times 10^{5}$ cm$ ^{2}$ /Vs and low percolation carrier density of $ (5.9\pm0.18)\times 10^{10}$ cm$ ^{-2}$ evidencing low disorder potential in the quantum well. The observed narrow statistical distribution of the transport properties highlights the reproducibility and the stability of the fabrication process. Furthermore, wafer-scale characterization of a selected individual wafer evidenced the homogeneity of the device performances across the wafer area. Based on these findings, we conclude that our material and processes provide a suitable platform for the development of scalable, Si/SiGe-based quantum devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
14 pages, 2 figures
Extending the capillary wave model to include the effect of bending rigidity: X-ray reflection and diffuse scattering
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-06-18 20:00 EDT
Chen Shen, Honghu Zhang, Beate Klösgen, Benjamin M. Ocko
The surface roughness of a thin film at a liquid interface exhibits contributions of thermally excited fluctuations. This thermal roughness depends on temperature (T), surface tension ($ \gamma$ ) and elastic material properties, specifically the bending modulus ($ \kappa$ ) of the film. A non-zero $ \kappa$ suppresses the thermal roughness at small length scales compared to an interface with zero $ \kappa$ , as expressed by the power spectral density (PSD) of the thermal roughness. The description of the X-ray scattering of the standard Capillary Wave Model (CWM), that is valid for zero $ \kappa$ , is extended to include the effect of $ \kappa$ . The extended CWM (eCWM) provides a single analytical form for both the specular XRR and the diffuse scattering around the specular reflection, and recovers the expression of the CWM at its zero $ \kappa$ limit. This new theoretical approach enables the use of single-shot grazing incidence X-ray off-specular scattering (GIXOS) measurements for characterizing the structure of thin films on a liquid surface. The eCWM analysis approach decouples the thermal roughness factor from the surface scattering signal, providing direct access to the intrinsic surface-normal structure of the film and its bending modulus. Moreover, the eCWM facilitates the calculation of reflectivity at any desired resolution (pseudo XRR approach). The transformation into pseudo XRR provides the benefit of using widely available XRR software to perform GIXOS analysis. The extended range of the vertical scattering vector (Qz) available with the GIXOS-pseudo XRR approach allows for a higher spatial resolution than with conventional XRR. Experimental results are presented for various lipid systems, showing strong agreement between conventional specular XRR and pseudo XRR methods. This agreement validates the proposed approach and highlights its utility for analyzing soft, thin films.
Soft Condensed Matter (cond-mat.soft)
30 pages, 11 figures
Complex single-site magnetism and magnetotransport in single-crystalline Gd${2}$AlSi${3}$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-18 20:00 EDT
Ram Kumar, Shanta R. Saha, Jarryd Horn, A. Ikeda, Danila Sokratov, Yash Anand, Prathum Saraf, Ryan Dorman, E. Hemley, K. K. Iyer, Johnpierre Paglione
We present a detailed investigation of single-crystal samples of the magnetic compound Gd$ _{2}$ AlSi$ _{3}$ , which crystallizes in the $ \alpha$ -ThSi$ 2$ type tetragonal structure. We report the temperature and magnetic field dependence of the magnetic susceptibility, magnetization, heat capacity, electrical resistivity, and magnetoresistance for magnetic fields applied along both the tetragonal $ c$ -axis and in the basal $ ab$ -plane. X-ray diffraction measurements confirm a centrosymmetric, $ I4{1}/amd$ space group of the crystal structure. Despite single-site occupancy of the Gd position in this tetragonal structure, we identify two successive antiferromagnetic phase transitions at Neél temperatures 32K and 23K via magnetic susceptibility, heat capacity and transport measurements, as well as a complex magnetic interaction with a magnetic anisotropy that plays an important role in the direction-dependent transport response. Our identification of multiple magnetic phases in Gd$ _{2}$ AlSi$ _{3}$ , where Gd is the only magnetic species, helps to elucidate the field-induced skyrmionic behavior in the Gd-based intermetallic compounds.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
10 pages, 9 figures
Phys. Rev. B 111, 214426 (2025)
Zigzag antiferromagnets in the SU(3) Hubbard model on the square lattice
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-06-18 20:00 EDT
Stijn V. Kleijweg, Philippe Corboz
SU(N) Hubbard models exhibit a rich variety of phases, which may be realized through quantum simulation with ultracold atomic gases in optical lattices. In this work we study the Mott insulating phases of the SU(3) Hubbard model at 1/3-filling using infinite projected entangled-pair states, optimized with both imaginary time evolution and variational optimization. In the limit of strong interactions we reproduce the antiferromagnetic 3-sublattice ordered state previously identified in the SU(3) Heisenberg model. At intermediate interaction strength we find antiferromagnetic states exhibiting zigzag patterns of different lengths, in agreement with previous Hartree-Fock and constrained-path auxiliary-field quantum Monte Carlo calculations. We study the color order parameter and energy anisotropy, which are discontinuous across the phase transitions. Finally, we analyze the different energy contributions in two competing phases, identifying low-energy bonds at the corners of the zigzag that help stabilize the zigzag states.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas)
10 pages, 7 figures
High-fidelity collisional quantum gates with fermionic atoms
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-18 20:00 EDT
Petar Bojović, Timon Hilker, Si Wang, Johannes Obermeyer, Marnix Barendregt, Dorothee Tell, Thomas Chalopin, Philipp M. Preiss, Immanuel Bloch, Titus Franz
Quantum simulations of electronic structure and strongly correlated quantum phases are widely regarded as among the most promising applications of quantum computing. These simulations require the accurate implementation of motion and entanglement of fermionic particles. Instead of the commonly applied costly mapping to qubits, fermionic quantum computers offer the prospect of directly implementing electronic structure problems. Ultracold neutral atoms have emerged as a powerful platform for spin-based quantum computing, but quantum information can also be processed via the motion of bosonic or fermionic atoms offering a distinct advantage by intrinsically conserving crucial symmetries like electron number. Here we demonstrate collisional entangling gates with fidelities up to 99.75(6)% and lifetimes of Bell states beyond $ 10,s$ via the control of fermionic atoms in an optical superlattice. Using quantum gas microscopy, we characterize both spin-exchange and pair-tunneling gates locally, and realize a robust, composite pair-exchange gate, a key building block for quantum chemistry simulations. Our results enable the preparation of complex quantum states and advanced readout protocols for a new class of scalable analog-digital hybrid quantum simulators. Once combined with local addressing, they mark a key step towards a fully digital fermionic quantum computer based on the controlled motion and entanglement of fermionic neutral atoms.
Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
16 pages, 18 figures
High-efficiency WSe$_2$ photovoltaics enabled by ultra-clean van der Waals contacts
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-06-18 20:00 EDT
Kamal Kumar Paul (1), Cullen Chosy (2 and 3), Soumya Sarkar (1), Zhuangnan Li (1), Han Yan (1), Ye Wang (1), Leyi Loh (1), Lixin Liu (1), Hu Young Jeong (4), Samuel D. Stranks (2 and 3), Yan Wang (1), Manish Chhowalla (1)
Layered transition metal dichalcogenide semiconductors are interesting for photovoltaics owing to their high solar absorbance and efficient carrier diffusion. Tungsten diselenide (WSe$ _2$ ), in particular, has emerged as a promising solar cell absorber. However, defective metal-semiconductor interfaces have restricted the power conversion efficiency (PCE) to approximately 6%. Here we report WSe$ _2$ photovoltaics with a record-high PCE of approximately 11% enabled by ultra-clean indium/gold (In/Au) van der Waals (vdW) contacts. Using grid-patterned top vdW electrodes, we demonstrate near-ideal diodes with a record-high on/off ratio of $ 1.0\times 10^9$ . Open-circuit voltage (VOC) of 571 +/- 9 mV, record-high short-circuit current density (JSC) of 27.19 +/- 0.45 mA cm$ ^{-2}$ – approaching the theoretical limit (34.5 mA cm$ ^{-2}$ ) – and fill factor of 69.2 +/- 0.7% resulting in PCE of 10.8 +/- 0.2% under 1-Sun illumination on large active area (approximately 0.13x0.13 mm$ ^2$ ) devices have been realised. The excellent device performance is consistent with the high external quantum efficiency (up to approximately 93%) measured across a broad spectral range of 500-830 nm. Our results suggest that ultra-clean vdW contacts on WSe$ _2$ enable high-efficiency photovoltaics and form the foundation for further optimisation.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Main manuscript with four figures and supplementary figures
Repulsive particle interactions enable selective information processing at cellular interfaces
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-06-18 20:00 EDT
Jenna Elliott, Hiral Shah, Roman Belousov, Gautam Dey, Anna Erzberger
Living systems relay information across membrane interfaces to coordinate compartment functions. We identify a physical mechanism for selective information transmission that arises from the sigmoidal response of surface-bound particle densities to spatial features of adjacent external structures. This mechanism implements a form of spatial thresholding, enabling the binary classification of external cues. Expansion microscopy measurements of nuclear pore complex distributions in S. arctica show signatures of such physical thresholding.
Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph)
23 pages, 6 figures
Quantum simulation of fermionic non-Abelian lattice gauge theories in $(2+1)$D with built-in gauge protection
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-06-18 20:00 EDT
Gaia De Paciani, Lukas Homeier, Jad C. Halimeh, Monika Aidelsburger, Fabian Grusdt
Recent advancements in the field of quantum simulation have significantly expanded the potential for applications, particularly in the context of lattice gauge theories (LGTs). Maintaining gauge invariance throughout a simulation remains a central challenge, especially for large-scale non-Abelian LGTs with dynamical matter, which are particularly complex in terms of engineering for experiments. Gauge-symmetry breaking is inevitable in established rishon-based schemes for alkaline-earth-like atoms (AELAs) and controlling the magnitude of its effect is an open challenge. Here, we first construct a minimal model to quantum simulate non-Abelian LGTs ensuring that the gauge constraints are met and explicitly derive their unambiguous non-Abelian nature. Second, we present a proposal for a novel gauge protection scheme using native interactions in AELAs enabling the simulation of toy models of non-Abelian $ U(2)$ LGTs with dynamical fermionic matter in $ (2+1)$ dimensions on large scales. Due to the simplicity of the gauge protection mechanism, based on a Zeeman shift in combination with superexchange interactions, our scheme can be naturally included in other rishon-based quantum simulation protocols. Third, we extend our approach to a fully scalable, hybrid digital-analog simulator for $ U(N)$ LGTs based on Rydberg AELA with variable rishon number. The proposed general mechanism for gauge protection provides a promising path towards the long-awaited simulation of non-Abelian LGTs relevant to particle physics.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
Fully Tunable Strong Spin-Orbit Interactions in Light Hole Germanium Quantum Channels
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-06-18 20:00 EDT
Patrick Del Vecchio, Stefano Bosco, Daniel Loss, Oussama Moutanabbir
Spin-orbit interaction (SOI) is a fundamental component for electrically driven spin qubits and hybrid superconducting-semiconducting systems. In particular, Rashba SOI (RSOI) is a key mechanism enabling all-electrical spin manipulation schemes. However, in common planar systems, RSOI is weak because of the small mixing between heavy holes (HH) and light holes (LH), and instead relies on complex strain and interface phenomena that are hard to reliably harness in experiment. Here, MOS-like epitaxial Ge on relaxed \GeSn{} is introduced and shown to exhibit an inherently large, highly gate-tunable RSOI that is compatible with both spin qubits and hybrid devices. This large RSOI is a consequence of the LH-like ground state in Ge. Notably, the built-in asymmetry of the device causes the RSOI to completely vanish at specific gate fields, effectively acting as an on/off SOI switch. The LH $ g$ -tensor is less anisotropic than that of state-of-the-art HH qubits, alleviating precise magnetic field orientation requirements. The large in-plane $ g$ -factor also facilitates the integration of superconductors. Moreover, the out-of-plane $ g$ -factor is strongly gate-tunable and completely vanishes at specific gate fields. Thus, this material system combines the large RSOI with the scalability of planar devices, paving the way towards robust spin qubit applications and enabling access to new regimes of complex spin physics.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)