CMP Journal 2025-09-25
Statistics
Science: 19
Physical Review Letters: 16
Physical Review X: 1
arXiv: 73
Science
Instability in the geological regulation of Earth’s climate
Research Article | Paleoclimate | 2025-09-25 03:00 EDT
Dominik Hülse, Andy Ridgwell
Negative feedback between climate and atmospheric carbon dioxide (CO2), mediated by the weathering of silicate minerals on land, is thought to provide the primary regulation of Earth’s climate on geological timescales. By contrast, we found that faster feedbacks involving organic matter are not only critical to Earth system recovery but can also create unexpected instability. Our Earth system model experiments show how sedimentary organic carbon burial, amplified by redox-sensitive phosphorus regeneration, can outweigh silicate weathering and paradoxically drive climate overcooling in response to massive CO2 release. This instability depends on the initial balance between silicate weathering and organic carbon burial in addition to the state of global phosphorus cycling. It is most strongly expressed at intermediate ocean redox states, which may help us understand the timing of past ice ages.
Dynamic U2AF cycling defines two phases of cotranscriptional pre-mRNA splicing
Research Article | Molecular biology | 2025-09-25 03:00 EDT
Changwei Shao, Yajing Hao, Li Jiang, Dong Wang, Rui Wang, Yuanjun Li, Hui Wang, Yaping Ge, Rui Bai, Xiangjuan Du, Xizi Chen, Tan Wu, Lan-Tao Gou, Ruixue Wan, Yanhui Xu, Xiong Ji, Xiang-Dong Fu
Distinguishing functional splice sites from abundant cryptic sites in precursor messenger RNAs (pre-mRNAs) represents a fundamental challenge in decoding mammalian genomes. We demonstrate that the specific RNA polymerase II (Pol II) subunit RPB9 directly interacts with the 3’ AG dinucleotide binding factor U2AF1 to initiate 3’ splice site recognition. Combined with recent structural insights into Pol II-mediated 5’ splice site selection, these findings support a cotranscriptional mechanism to recognize paired 3’ and 5’ splice sites across individual exons. These initial exon definition events facilitate the recruitment of U2AF2 to heterodimerize with U2AF1, which also triggers U2AF1 release from elongating Pol II. Collectively, these results reveal dynamic U2AF cycling that partitions Pol II subunit-facilitated splice site recognition and subsequent Pol II-independent spliceosome assembly steps during cotranscriptional splicing.
Mechanosensitive genomic enhancers potentiate the cellular response to matrix stiffness
Research Article | 2025-09-25 03:00 EDT
Brian D. Cosgrove, Lexi R. Bounds, Carson Key Taylor, Alan L. Su, Anthony J. Rizzo, Alejandro Barrera, Tongyu Sun, Alexias Safi, Lingyun Song, Thomas Whitlow, Aleksandra Tata, Nahid Iglesias, Yarui Diao, Purushothama Rao Tata, Brenton D. Hoffman, Gregory E. Crawford, Charles A. Gersbach
Epigenetic control of gene expression and cellular phenotype is influenced by changes in the local microenvironment, yet how mechanical cues precisely influence epigenetic state to regulate transcription remains largely unmapped. Here, we combine genome-wide epigenome profiling, epigenome editing, and phenotypic and single-cell RNA-seq CRISPR screening to identify a class of genomic enhancers that responds to the mechanical microenvironment. These “mechanoenhancers” can be preferentially activated on either soft or stiff extracellular matrix contexts and regulate transcription to influence critical cell functions including apoptosis, adhesion, proliferation, and migration. Epigenetic editing of mechanoenhancers reprograms the cellular response to the mechanical microenvironment and modulates the activation of disease-related genes in lung fibroblasts from healthy and fibrotic donors. Epigenetic editing of mechanoenhancers holds potential for precise targeting of mechanically-driven diseases.
Lysosomes signal through the epigenome to regulate longevity across generations
Research Article | Aging | 2025-09-25 03:00 EDT
Qinghao Zhang, Weiwei Dang, Meng C. Wang
The epigenome is sensitive to metabolic inputs and is crucial for aging. Lysosomes act as a signaling hub to sense metabolic cues and regulate longevity. We found that lysosomal metabolic pathways signal through the epigenome to regulate transgenerational longevity in Caenorhabditis elegans. Activation of lysosomal lipid signaling and lysosomal adenosine monophosphate-activated protein kinase (AMPK) or reduction of lysosomal mechanistic target of rapamycin (mTOR) signaling increased the expression of a histone H3.3 variant and increased its methylation on K79, leading to life-span extension across multiple generations. This transgenerational prolongevity effect required intestine-to-germline transportation of histone H3.3 and a germline-specific H3K79 methyltransferase and was recapitulated by overexpressing H3.3 or the H3K79 methyltransferase. Thus, signals from a lysosome affect the epigenome and link the soma and germ line to mediate transgenerational inheritance of longevity.
The phylogenetic position of the Yunxian cranium elucidates the origin of Homo longi and the Denisovans
Research Article | Anthropology | 2025-09-25 03:00 EDT
Xiaobo Feng, Qiyu Yin, Feng Gao, Dan Lu, Qin Fang, Yilu Feng, Xuchu Huang, Chen Tan, Hanwen Zhou, Qiang Li, Chi Zhang, Chris Stringer, Xijun Ni
Diverse forms of Homo coexisted during the Middle Pleistocene. Whether these fossil humans represent different species or clades is debated. The ~1-million-year-old Yunxian 2 fossil from China is important for understanding the cladogenesis of Homo and the origin of Homo sapiens. In this study, we restored and reconstructed the distorted Yunxian 2 cranium using recently introduced technology. The results show that this cranium displays mosaic primitive and derived features. Morphometric and phylogenetic analyses suggest that it is an early member of the Asian H. longi clade, which includes the Denisovans and is the main part of the sister group to the H. sapiens clade. Both the H. sapiens and H. longi clades have deep roots extending beyond the Middle Pleistocene and probably experienced rapid early diversification. Yunxian 2 may preserve transitional features close to the origins of the two clades.
Pre- and postantibiotic epoch: The historical spread of antimicrobial resistance
Research Article | 2025-09-25 03:00 EDT
Adrian Cazares, Wendy Figueroa, Daniel Cazares, Leandro Lima, Jake D. Turnbull, Hannah McGregor, Jo Dicks, Sarah Alexander, Zamin Iqbal, Nicholas R. Thomson
Plasmids are now the primary vectors of antimicrobial resistance, but our understanding of how human industrialisation of antibiotics influenced their evolution is limited by a paucity of data predating the antibiotic era (PAE). By investigating plasmids from clinically relevant bacteria sampled and isolated between 1917 and 1954 and comparing them to modern plasmids, we have captured over 100 years of evolution. We show that while virtually all PAE plasmids were devoid of resistance genes and most never acquired them, a minority evolved to drive the global spread of resistance to first line and last resort antibiotics in Gram-negative bacteria. Modern plasmids have evolved through complex microevolution and fusion events into a distinct group of highly recombinogenic, multi-replicon, self-transmissible plasmids that now pose the highest risk to resistance dissemination, and therefore to human health.
Critical habitat thresholds for effective pollinator conservation in agricultural landscapes
Research Article | Conservation biology | 2025-09-25 03:00 EDT
Gabriella A. Bishop, David Kleijn, Matthias Albrecht, Ignasi Bartomeus, Rufus Isaacs, Claire Kremen, Ainhoa Magrach, Lauren C. Ponisio, Simon G. Potts, Jeroen Scheper, Henrik G. Smith, Teja Tscharntke, Jörg Albrecht, Jens Åström, Isabelle Badenhausser, András Báldi, Parthiba Basu, Åsa Berggren, Nicole Beyer, Nico Blüthgen, Riccardo Bommarco, Berry J. Brosi, Hamutahl Cohen, Lorna J. Cole, Kathy R. Denning, Mariano Devoto, Johan Ekroos, Felix Fornoff, Bryan L. Foster, Mark A.K. Gillespie, Jose L. Gonzalez-Andujar, Juan P. González-Varo, Dave Goulson, Ingo Grass, Annika L. Hass, José M. Herrera, Andrea Holzschuh, Sebastian Hopfenmüller, Jordi Izquierdo, Birgit Jauker, Eveliina P. Kallioniemi, Felix Kirsch, Alexandra-Maria Klein, Anikó Kovács-Hostyánszki, Jochen Krauss, Elena Krimmer, William E. Kunin, Supratim Laha, Sandra A.M. Lindström, Yael Mandelik, Gabriel Marcacci, David I. McCracken, Marcos Monasterolo, Lora A. Morandin, Jane Morrison, Sonja Mudri Stojnic, Jeff Ollerton, Anna S. Persson, Benjamin B. Phillips, Julia I. Piko, Eileen F. Power, Gabriela M. Quinlan, Maj Rundlöf, Chloé A. Raderschall, Laura G.A. Riggi, Stuart P.M. Roberts, Tohar Roth, Deepa Senapathi, Dara A. Stanley, Ingolf Steffan-Dewenter, Jane C. Stout, Louis Sutter, Marco F. Tanis, Sam Tarrant, Lisette van Kolfschoten, Adam J. Vanbergen, Montserrat Vilà, Vivien von Königslöw, Ante Vujic, Michiel F. WallisDeVries, Ai Wen, Catrin Westphal, Jennifer B. Wickens, Victoria J. Wickens, Nicholas I. Wilkinson, Thomas J. Wood, Thijs P. M. Fijen
Biodiversity in human-dominated landscapes is declining, but evidence-based conservation targets to guide international policies for such landscapes are lacking. We present a framework for informing habitat conservation policies based on the enhancement of habitat quantity and quality and define thresholds of habitat quantity at which it becomes effective to also prioritize habitat quality. We applied this framework to insect pollinators, an important part of agroecosystem biodiversity, by synthesizing 59 studies from 19 countries. Given low habitat quality, hoverflies had the lowest threshold at 6% semi-natural habitat cover, followed by solitary bees (16%), bumble bees (18%), and butterflies (37%). These figures represent minimum habitat thresholds in agricultural landscapes, but when habitat quantity is restricted, marked increases in quality are required to reach similar outcomes.
Fungus-farming termites can protect their crop by confining weeds with fungistatic soil boluses
Research Article | Natural history | 2025-09-25 03:00 EDT
Aanchal Panchal, Ruchira Sen, Renuka Agarwal, Anjali Rana, Rhitoban Raychoudhury
The symbiotic agriculture of fungus-farming termites can collapse if they fail to prevent invading weeds. Previous studies suggest a role for symbiotic fungistatic microbes in bringing about weed control. However, how termites employ these microbes to suppress fungal weeds without affecting the fungal cultivar remains unknown. We show that the fungus-farming termite Odontotermes obesus uses specific behaviors to remove, isolate, and suppress the growth of the fungal weed Pseudoxylaria, primarily by encasing it with soil boluses containing fungistatic microbes. These behaviors efficiently suppress the weed without affecting the crop. This integration of specific behaviors with termite-derived microbes appears to be the proximate mechanism of how microbes are topically used by termites to confine the weed while keeping the crop unaffected.
Global selection on insect antipredator coloration
Research Article | Predation avoidance | 2025-09-25 03:00 EDT
Iliana Medina, Alice Exnerová, Klára Daňková, Olivier Penacchio, Tom N. Sherratt, Tomáš Albrecht, Sarika Baidya, Renan Janke Bosque, Héloïse Brown, Emily Burdfield-Steel, Kristal E. Cain, Rodrigo Roucourt Cezário, Ylenia Chiari, Carolina Esquivel, Rhainer Guillermo Ferreira, Amanda M. Franklin, Aloise Garvey, Samuel Guchu, Brandon T. Hastings, Kateřina Hotová-Svádová, Yerin Hwang, Changku Kang, John Kasaya, Jennifer Kelley, Yongsu Kim, Krushnamegh Kunte, Felipe Daetto-Liberato, Karl Loeffler-Henry, Vinicius Marques Lopez, Claire MacKay-Dietrich, Johanna Mappes, María Cecilia De Mársico, Viraj Nawge, Peter Njoroge, Ossi Nokelainen, Arka Pal, Archan Paul, Robert Posont, Jan Raška, Juan Carlos Reboreda, Juan Manuel Rojas Ripari, Hannah M. Rowland, Maria de las Nieves Sabio, Camilo Salazar, Fabian C. Salgado-Roa, Steve A. Stephens-Cárdenas, Anita Szabó, Juan Pablo Mongui Torres, Jolyon Troscianko, Marie Truhlářová, Kate D. L. Umbers, Molly Venton, Makenzie Vitasovich, Lu-Yi Wang, Sarah-Sophie Weil, William L. Allen
Natural selection has repeatedly led to the evolution of two alternative antipredator color strategies–camouflage to avoid detection and aposematism to advertise unprofitability–but we lack understanding of how ecological context favors one strategy over the other. We conducted a globally replicated predation experiment at 21 sites on six continents to test how predator community, prey community, and visual environment influenced the predation risk of 15,018 artificial paper “moth” prey with cryptic or warning coloration. Results indicated that aposematic strategies fare better in environments with low predation intensity, whereas camouflage strategies are advantaged when other camouflaged prey species are rare and when light levels are low. This study demonstrates how multiple mechanisms shape antipredator strategies, helping to explain the evolution and global distribution of camouflaged and aposematic animals.
Predicting protein-protein interactions in the human proteome
Research Article | 2025-09-25 03:00 EDT
Jing Zhang, Ian R. Humphreys, Jimin Pei, Jinuk Kim, Chulwon Choi, Rongqing Yuan, Jesse Durham, Siqi Liu, Hee-Jung Choi, Minkyung Baek, David Baker, Qian Cong
Protein-protein interactions (PPI) are essential for biological function. Coevolutionary analysis and deep learning (DL) based protein structure prediction have enabled comprehensive PPI identification in bacteria and yeast, but these approaches have had limited success for the more complex human proteome. We overcame this challenge by enhancing the coevolutionary signals with 7-fold deeper multiple sequence alignments harvested from 30 petabytes of unassembled genomic data and developing a new DL network trained on augmented datasets of domain-domain interactions from 200 million predicted protein structures. We systematically screened 200 million human protein pairs and predicted 17,849 interactions with an expected precision of 90%, of which 3,631 interactions were not identified in previous experimental screens. Three-dimensional models of these predicted interactions provide numerous hypotheses about protein function and mechanisms of human diseases.
Dual transposon sequencing profiles the genetic interaction landscape in bacteria
Research Article | Systems biology | 2025-09-25 03:00 EDT
Justin J. Zik, Morgan N. Price, Keisha Hanifa Alma Mayra, Audrey A. Santoso, Adam P. Arkin, Adam M. Deutschbauer, Lok-To Sham
Gene redundancy complicates systematic characterization of gene function as single-gene deletions may not produce discernible phenotypes. We report dual transposon sequencing (dual Tn-seq), a platform for assaying the fitness of a comprehensive double mutant pool in parallel. Dual Tn-seq couples random barcode transposon site sequencing with the Cre-lox system, enabling deep sampling of 73% of the 1.3 million possible double gene deletions in Streptococcus pneumoniae. The genetic interactions identified span a wide range of biochemical processes, revealing new factors in presumably well-studied pathways, exemplified by a cytidine triphosphate synthase PyrJ. Moreover, this approach should permit further investigation of growth condition-specific genetic interactions. Because dual Tn-seq does not require the construction of a large array of single mutants, it should be readily adaptable to various microorganisms.
Identification of short-range ordering motifs in semiconductors
Research Article | Semiconductors | 2025-09-25 03:00 EDT
Lilian M. Vogl, Shunda Chen, Peter Schweizer, Xiaochen Jin, Shui-Qing Yu, Jifeng Liu, Tianshu Li, Andrew M. Minor
Chemical short-range ordering is expected to be a key factor for tuning the electronic structure of semiconductors. However, experimental evidence of short-range ordering is still lacking due to the challenge of characterizing atomic-scale ordering motifs. Here, we determined the presence of short-range order in a ternary GeSiSn semiconductor system using advanced energy-filtered four-dimensional scanning transmission electron microscopy and large-scale atomistic models generated by a machine learning neuroevolution potential of first-principles accuracy. This approach revealed preferred ordering of different atomic species with the dominant occurrence of Si-Ge-Sn triplets. Our findings not only confirmed the presence of short-range order but also directly revealed the actual atomic structure, demonstrating the potential for informed atomic order-based band engineering as a third degree of freedom beyond composition and strain tuning.
Quantum learning advantage on a scalable photonic platform
Research Article | Quantum processing | 2025-09-25 03:00 EDT
Zheng-Hao Liu, Romain Brunel, Emil E. B. Østergaard, Oscar Cordero, Senrui Chen, Yat Wong, Jens A. H. Nielsen, Axel B. Bregnsbo, Sisi Zhou, Hsin-Yuan Huang, Changhun Oh, Liang Jiang, John Preskill, Jonas S. Neergaard-Nielsen, Ulrik L. Andersen
Recent advances in quantum technologies have demonstrated that quantum systems can outperform classical ones in specific tasks, a concept known as quantum advantage. Although previous efforts have focused on computational speedups, a definitive and provable quantum advantage that is unattainable by any classical system has remained elusive. In this work, we demonstrate a provable photonic quantum advantage by implementing a quantum-enhanced protocol for learning a high-dimensional physical process. Using imperfect Einstein-Podolsky-Rosen entanglement, we achieve a sample complexity reduction of 11.8 orders of magnitude compared to classical methods without entanglement. These results show that large-scale, provable quantum advantage is achievable with current photonic technology and represent a key step toward practical quantum-enhanced learning protocols in quantum metrology and machine learning.
Full utilization of noble metals by atom abstraction for propane dehydrogenation
Research Article | 2025-09-25 03:00 EDT
Guodong Sun, Ran Luo, Donglong Fu, Kexin Wu, Xianhui Wang, Xiaoqing Bian, Zhenpu Lu, Xin Chang, Zhi Wang, Siwei Huang, Yihan Zhu, Jihan Zhou, Sai Chen, Chunlei Pei, Zhi-Jian Zhao, Jinlong Gong
Maximizing atomic utilization of noble metals is crucial for efficient industrial catalysis. We demonstrate that minimal platinum (Pt) loading for propane dehydrogenation (PDH) can be achieved through atom abstraction. At low loadings of Pt with copper (Cu), reduction over silica or other oxide supports formed nanoparticles (NPs) with Pt mainly dispersed in the bulk. Addition of tin (Sn) to the alloy led to formation of surface Pt1Sn1 dimers. The larger atomic radius of Sn compared to Cu drove it to the surface, and its stronger interactions with Pt abstracted it from the bulk. Single metallic Pt atoms were stabilized on fully open surfaces, resulting in nearly 100% surface exposure. This configuration reduced Pt usage by one order of magnitude for propane dehydrogenation and improved catalytic stability.
Neural basis of cooperative behavior in biological and artificial intelligence systems
Research Article | 2025-09-25 03:00 EDT
Mengping Jiang, Linfan Gu, Mingyi Ma, Qin Li, Jonathan C. Kao, Weizhe Hong
Cooperation, the process through which individuals work together to achieve common goals, is fundamental to human and animal societies and increasingly critical in artificial intelligence. Here, we investigated cooperation in mice and artificial intelligence systems, examining how they learn to actively coordinate their actions to obtain shared rewards. We identified key social behavioral strategies and decision-making processes in mice that facilitate successful cooperation. These processes are represented in the anterior cingulate cortex (ACC) and ACC activity causally contributes to cooperative behavior. We extended our findings to artificial intelligence systems by training artificial agents in a similar cooperation task. The agents developed behavioral strategies and neural representations reminiscent of those observed in the biological brain, revealing parallels between cooperative behavior in biological and artificial systems.
Diversity-oriented photobiocatalytic synthesis via stereoselective three-component radical coupling
Research Article | Biocatalysis | 2025-09-25 03:00 EDT
Chen Zhang, Jun Zhou, Pei-Pei Xie, Silvia M. Rivera, Turki M. Alturaifi, James Finnigan, Simon Charnock, Peng Liu, Yang Yang
Enzymatic multicomponent carbon-carbon (C-C) bond-forming reactions for diversity-oriented synthesis remain rare. Using cooperative photobiocatalysis, we developed a stereoselective three-component radical-mediated C-C coupling previously unknown in both organic chemistry and biochemistry. Directed evolution of repurposed pyridoxal decarboxylases enabled full fragment variability in this three-component coupling, giving rise to six classes of valuable products, many of which were inaccessible with other methods, even in a racemic fashion. This enzymatic platform integrates a range of asymmetric catalysis principles, including remote stereocenter construction, stereodivergent catalysis, kinetic resolution, and parallel kinetic resolution, achieving excellent diastereo- and enantiocontrol over radical intermediates. The broad substrate scope and complementary specificities of evolved enzyme variants enabled combinatorial library synthesis, affording structurally and stereochemically diverse scaffolds for medicinal chemistry.
Deazaguanylation is a nucleobase-protein conjugation required for type IV CBASS immunity
Research Article | Bacterial immunity | 2025-09-25 03:00 EDT
Douglas R. Wassarman, Patrick Pfaff, Joao A. Paulo, Steven P. Gygi, Kevan M. Shokat, Philip J. Kranzusch
7-Deazapurines are nucleobase analogs essential for nucleic acid modifications in nearly all cellular life. In this study, we discovered a role for 7-deazapurines in protein modification within type IV cyclic oligonucleotide-based antiviral signaling system (CBASS) antiphage defense and defined functions for CBASS ancillary proteins Cap9 and Cap10 in nucleobase-protein conjugation. A structure of Cap10 revealed a transfer RNA transglycosylase family enzyme remodeled to bind a partner cGAS/DncV-like nucleotidyltransferase that is modified with an N-terminal 7-amido-7-deazaguanine (NDG) nucleobase. A structure of Cap9 explained how this QueC-like enzyme co-opts a 7-deazapurine biosynthetic reaction to install NDG. We show that Cap9, Cap10, and protein deazaguanylation are essential for host defense against phage infection. Our results define a 7-deazapurine protein modification and explain how nucleobase biosynthetic machinery has been repurposed for antiviral immunity.
Fiber-imaged supershear dynamics in the 2024 Mw 7 Mendocino Fault earthquake
Research Article | Earthquake dynamics | 2025-09-25 03:00 EDT
James Atterholt, Jeffrey J. McGuire, Andrew J. Barbour, Connie Stewart, Morgan P. Moschetti
Fault structure and rupture physics are deeply intertwined, and observations of this coupling are critical for understanding earthquake behavior. Rupture propagation is observable at fine scales using dense seismic networks. Fiber-optic sensing allows for long-term deployments of ultradense arrays that enable high-resolution measurements of infrequent, large earthquakes. We recorded the 2024 moment magnitude (Mw) 7 Mendocino Fault earthquake with a nearby fiber-optic array and imaged its behavior with seismic beamforming. The rupture propagated to the east at subshear velocity; stagnated near the Mendocino Triple Junction, a zone of structural complexity; and subsequently transitioned to supershear velocity. The correlation between source physics and structure shows how lithospheric heterogeneity affects first-order characteristics of earthquake ruptures. Our results also demonstrate the potential for fiber-optic sensing to improve real-time estimation of key parameters for early warning.
Megabase-scale human genome rearrangement with programmable bridge recombinases
Research Article | 2025-09-25 03:00 EDT
Nicholas T. Perry, Liam J. Bartie, Dhruva Katrekar, Gabriel A. Gonzalez, Matthew G. Durrant, James J. Pai, Alison Fanton, Juliana Q. Martins, Masahiro Hiraizumi, Chiara Ricci-Tam, Hiroshi Nishimasu, Silvana Konermann, Patrick D. Hsu
Bridge recombinases are naturally occurring RNA-guided DNA recombinases that we previously demonstrated can programmably insert, excise, and invert DNA in vitro and in Escherichia coli. In this study, we report the discovery and engineering of the bridge recombinase ortholog ISCro4 for universal rearrangements of the human genome. We defined strategies for the optimal application of bridge systems, leveraging mechanistic insights to improve their targeting specificity. Through rational engineering of the ISCro4 bridge RNA and deep mutational scanning of its recombinase, we achieved up to 20% insertion efficiency into the human genome and genome-wide specificity as high as 82%. We further demonstrated intrachromosomal inversion and excision, mobilizing up to 0.93 megabases of DNA. Lastly, we provided proof-of-concept for plasmid-based excision of disease-relevant gene regulatory regions or repeat expansions.
Physical Review Letters
New Limits on Ultralight Axionlike Dark Matter from Reanalyzed Data
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-24 06:00 EDT
K. Y. Zhang, L. Y. Wu, and H. Yan
New limits on the axion-nucleon coupling over the axion mass region are derived by reanalyzing data from laboratory measurements on Lorentz and violations. These results establish the first laboratory constraints on the axion-nucleon coupling for axion masses below …
Phys. Rev. Lett. 135, 131001 (2025)
Cosmology, Astrophysics, and Gravitation
Nailing Down the Theoretical Uncertainties of $\overline{\mathrm{D}}$ Spectrum Produced from Dark Matter
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-24 06:00 EDT
Mattia Di Mauro, Nicolao Fornengo, Adil Jueid, Roberto Ruiz de Austri, and Francesca Bellini
The detection of cosmic antideuterons () at kinetic energies below a few could provide a smoking gun signature for dark matter (DM). However, the theoretical uncertainties of coalescence models have represented so far one of the main limiting factors for precise predictions of the flux. I…
Phys. Rev. Lett. 135, 131002 (2025)
Cosmology, Astrophysics, and Gravitation
Recursive Landau Analysis
Article | Particles and Fields | 2025-09-24 06:00 EDT
Simon Caron-Huot, Miguel Correia, and Mathieu Giroux
We propose a recursive method that makes use of the basic principle of unitarity to calculate the Landau singularities of -point scattering amplitudes directly in kinematic space. For a vast class of Feynman diagrams, the method enables rapid analytic computation of Landau singularities beyond curr…
Phys. Rev. Lett. 135, 131603 (2025)
Particles and Fields
Next-to-Leading-Order QCD Corrections to Nucleon Dirac Form Factors
Article | Particles and Fields | 2025-09-24 06:00 EDT
Long-Bin Chen, Wen Chen, Feng Feng, Siwei Hu, and Yu Jia
The leading-order perturbative QCD (pQCD) predictions for nucleon electromagnetic form factors were first made in late 1970s. In this Letter, for the first time, we accomplish the calculation of the next-to-leading-order (NLO) QCD corrections to nucleon Dirac form factors at large momentum transfer …
Phys. Rev. Lett. 135, 131903 (2025)
Particles and Fields
Optical Lattice Quantum Simulator of Dynamics beyond Born-Oppenheimer
Article | Atomic, Molecular, and Optical Physics | 2025-09-24 06:00 EDT
Javier Argüello-Luengo, Alejandro González-Tudela, and J. Ignacio Cirac
Here, we propose a platform based on ultracold fermionic molecules trapped in optical lattices to simulate nonadiabatic effects, as they appear in certain molecular dynamical problems. The idea consists of a judicious choice of two rotational states as the simulated electronic or nuclear degrees of …
Phys. Rev. Lett. 135, 133402 (2025)
Atomic, Molecular, and Optical Physics
Universal Kerr-Thermal Dynamics of Self-Injection-Locked Microresonator Dark Pulses
Article | Atomic, Molecular, and Optical Physics | 2025-09-24 06:00 EDT
Shichang Li, Kunpeng Yu, Dmitry A. Chermoshentsev, Wei Sun, Jinbao Long, Xiaoying Yan, Chen Shen, Artem E. Shitikov, Nikita Yu. Dmitriev, Igor A. Bilenko, and Junqiu Liu
Microcombs, formed in optical microresonators driven by continuous-wave lasers, are miniaturized optical frequency combs. Leveraging integrated photonics and laser self-injection locking, compact microcombs can be constructed via hybrid integration of a semiconductor laser with a chip-based microres…
Phys. Rev. Lett. 135, 133803 (2025)
Atomic, Molecular, and Optical Physics
Vibrational Modes and Particle Rearrangements in Sheared Quasi-Two-Dimensional Complex Plasmas
Article | Plasma and Solar Physics, Accelerators and Beams | 2025-09-24 06:00 EDT
Yang Miao, Alexei V. Ivlev, Hartmut Löwen, Volodymyr Nosenko, He Huang, Wei Yang, Hubertus M. Thomas, Jing Zhang, and Cheng-Ran Du
Shearing a dusty plasma with a laser shows how vibrational modes lead to weak points in an amorphous active system.
Phys. Rev. Lett. 135, 135301 (2025)
Plasma and Solar Physics, Accelerators and Beams
Unified High-Pressure Phase-Transition Sequence in the $f$-Electron Metals: $oF16→oF8$ Transition in Terbium
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
C. V. Storm, S. E. Finnegan, J. D. McHardy, M. J. Duff, M. I. McMahon, S. G. MacLeod, E. Plekhanov, and C. Weber
The lanthanide elements have long been reported as having a common series of structural phase transitions on compression, but recent diffraction studies have revealed two series of transitions: one in the low-Z lanthanides (Nd and Sm) involving an 8-atom orthorhombic structure (), also seen in so…
Phys. Rev. Lett. 135, 136101 (2025)
Condensed Matter and Materials
Spatially Resolved Vibronic Excitations of an Isolated Adsorbed Organometallic Complex via Multiple Tunneling Channels
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Xiangzhi Meng, Kai Uwe Clausen, Marie-Laure Bocquet, Alexander Weismann, Niklas Ide, Felix Tuczek, and Richard Berndt
Vibronic excitations of molecules at nanoscale interfaces are important for molecular electronics and spintronics and have therefore attracted considerable attention. For single molecules in mechanically controlled break junctions or in a scanning tunneling microscope (STM), vibronic excitations are…
Phys. Rev. Lett. 135, 136202 (2025)
Condensed Matter and Materials
Carrier Localization and Spontaneous Formation of Two-Dimensional Polarization Domain in Halide Perovskites
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Andrew Grieder, Marcos Calegari Andrade, Hiroyuki Takenaka, Tadashi Ogitsu, Liang Z. Tan, and Yuan Ping
Halide perovskites are known for their rich phase diagram and superior performance in diverse optoelectronics applications. The latter property is often attributed to the long electron-hole recombination time, whose underlying physical mechanism has been a long-standing controversy. In this Letter, …
Phys. Rev. Lett. 135, 136301 (2025)
Condensed Matter and Materials
Self-Reconstruction of Order Parameter in Spin-Triplet Superconductor ${\mathrm{UTe}}_{2}$
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Y. Tokiwa, P. Opletal, H. Sakai, K. Kubo, S. Kambe, E. Yamamoto, M. Kimata, S. Awaji, T. Sasaki, D. Aoki, Y. Yanase, Y. Tokunaga, and Y. Haga
We investigate the effect of easy-axis metamagnetic crossover on superconductivity in along the axis through measurements of ac susceptibility, magnetization, and the magnetocaloric effect. In ultraclean single crystals, we identify a field-induced phase transition within the superconducting …
Phys. Rev. Lett. 135, 136502 (2025)
Condensed Matter and Materials
Band Renormalization, Quarter Metals, and Chiral Superconductivity in Rhombohedral Tetralayer Graphene
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Guillermo Parra-Martínez, Alejandro Jimeno-Pozo, Võ Tiến Phong, Héctor Sainz-Cruz, Daniel Kaplan, Peleg Emanuel, Yuval Oreg, Pierre A. Pantaleón, José Ángel Silva-Guillén, and Francisco Guinea
Recently, exotic superconductivity emerging from a spin-and-valley-polarized metallic phase has been discovered in rhombohedral tetralayer graphene. To explain this observation, we study the role of electron-electron interactions in driving flavor symmetry breaking, using the Hartree-Fock (HF) appro…
Phys. Rev. Lett. 135, 136503 (2025)
Condensed Matter and Materials
Simulating the Two-Dimensional $t\text{-}J$ Model at Finite Doping with Neural Quantum States
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Hannah Lange, Annika Böhler, Christopher Roth, and Annabelle Bohrdt
Simulating large, strongly interacting fermionic systems remains a major challenge for existing numerical methods. In this Letter, we introduce Gutzwiller projected hidden fermion determinant states (G-HFDS) to simulate the strongly interacting limit of the Fermi-Hubbard model, namely the model,…
Phys. Rev. Lett. 135, 136504 (2025)
Condensed Matter and Materials
Observation of Embedded Topology in a Trivial Bulk via Projective Crystal Symmetry
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Hau Tian Teo, Yang Long, Hong-yu Zou, Kailin Song, Haoran Xue, Yong Ge, Shou-qi Yuan, Hong-xiang Sun, and Baile Zhang
A new topological mechanism, wherein dimension reduction and projective crystal symmetry create embedded topology from a trivial bulk, redefines the conventional hierarchy of bulk-boundary correspondence.
Phys. Rev. Lett. 135, 136602 (2025)
Condensed Matter and Materials
Thermal Spin Wave Noise as a Probe for the Dzyaloshinskii-Moriya Interaction
Article | Condensed Matter and Materials | 2025-09-24 06:00 EDT
Aurore Finco, Pawan Kumar, Van Tuong Pham, Joseba Urrestarazu-Larrañaga, Rodrigo Guedas Garcia, Maxime Rollo, Olivier Boulle, Joo-Von Kim, and Vincent Jacques
Interfacial Dzyaloshinskii-Moriya interaction (DMI) is a key ingredient in the stabilization of chiral magnetic states in thin films. Its sign and strength often determine crucial properties of magnetic objects, like their topology or how they can be manipulated with currents. A few experimental tec…
Phys. Rev. Lett. 135, 136703 (2025)
Condensed Matter and Materials
Scaling Laws for Passive Polymer Dynamics in Active Turbulence
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-09-24 06:00 EDT
Zahra K. Valei and Tyler N. Shendruk
Biological systems commonly combine intrinsically out-of-equilibrium active components with passive polymeric inclusions to produce unique material properties. To explore these composite systems, idealized models--such as polymers in active fluids--are essential to develop a predictive theoretical fra…
Phys. Rev. Lett. 135, 138301 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Physical Review X
Two-Dopant Origin of Competing Stripe and Pair Formation in Hubbard and $t\text{-}J$ Models
Article | | 2025-09-24 06:00 EDT
Tizian Blatz, Ulrich Schollwöck, Fabian Grusdt, and Annabelle Bohrdt
A single pair of charge carriers can reveal the competition between superconducting and insulating phases in the microscopic models describing high-temperature superconductors.
Phys. Rev. X 15, 031074 (2025)
arXiv
Introduction to some of the simplest topological phases of matter
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
These lecture notes explain the classification of some simple fermionic topological phases of matter in a pedestrian manner, with an aim to be maximally pedagogical = doing things in excruciating detail. We focus on a many-body perspective, even if many of the models we work with are non-interacting. We start out with symmetry protected topological (SPT) phases of free fermions that are protected by U(1) symmetry = topological insulators. We then look at fermion topological phases that don’t even need a symmetry = topological superconductors, and explain how their classification changes in presence of spinless time-reversal symmetry. We close by perturbatively checking which of the 1D topological phases we had found are stable to interactions.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
39 pages, 3 figures, lecture notes from the 2025 Bad Honnef summer school “Symmetry protected topological phases”
Artificial ferroelectric-like hysteresis in antiferroelectrics with non-uniform disorder
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Yi Zhang, Xinyu Zhang, Zihao Zheng, Jiyang Xie, Jing Lou, Jiayi Qin, Shanhu Wang, Yang He, Yifeng Du, Bin Yang, Xin Huang, Huiping Han, Yilin Wu, Shuya Liu, Afzal Kjan, Zhidong Li, Qianxu Ye, Sheng’an Yang, Ji Ma, Hui Zhang, Xiang Liu, Qingming Chen, Wanbiao Hu, Jing Ma, Jianhong Yi, Jinming Guo, Shou Peng, Hao Pan, Liang Wu, Ce-Wen Nan
Antiferroelectrics exhibit unique double-hysteresis polarization loops, which have garnered significant attention due to their potential applications such as energy storage, electromechanical transduction, as well as synapse devices. However, numerous antiferroelectric materials have been reported to display signs of hysteresis loops resembling those of ferroelectric materials, and a comprehensive understanding remains elusive. In this work, we provide a phenomenological model that reproduces such widely observed artificial ferroelectric hysteresis with a superposition of numerous disordered antiferroelectric loops that have varying antiferroelectric-to-ferroelectric transition fields, particularly when these field ranges intersect. Experimentally, we realized such artificial ferroelectric-like hysteresis loops in the prototypical antiferroelectric PbZrO$ _3$ and PbHfO$ _3$ thin films, by introducing non-uniform local disorder (e.g., defects) via fine-tuning of the film growth conditions. These ferroelectric-like states are capable of persisting for several hours prior to transitioning back into the thermodynamically stable antiferroelectric ground state. Those results provide insights into the fundamental impact of disorder on the AFE properties and new possibilities of disorder-tailored functions.
Materials Science (cond-mat.mtrl-sci)
Acta Materialia, 294, (2025), 121085
Dynamical localization of interacting ultracold atoms in one-dimensional quasi-periodic potentials
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-09-25 20:00 EDT
Attis V. M. Marino, M. A. Caracanhas, V. S. Bagnato, B. Chakrabarti
We present numerically exact non-equilibrium dynamics of a one-dimensional Bose gas in quasi-periodic lattice that plays an intermediate role between the long-ranged order and truly disordered systems exhibiting unusual correlated phases. Precision control over lattice depth, interaction strength and filling factor enables the exploration of various correlated phases in a finite periodic lattice. We investigate the system dynamics when the secondary incommensurate lattice is abruptly switched on. To solve the many-body Schroedinger equation, we employ the multiconfigurational time-dependent Hartree method for bosons (MCTDHB). The many-body dynamics are analyzed through distinct measures of the Glauber correlation functions and dynamical fragmentation. Our study reveals four distinct scenarios of localization process in the non-equilibrium dynamics. Weakly interacting non-fragmented superfluid of incommensurate filling in the primary lattice exhibits collapse-revival dynamics of localization. In contrast, a fragmented superfluid with commensurate filling exhibits dynamical Mott localization. A strongly correlated, fully fragmented Mott state shows a subtle competition with localization introduced by the secondary lattice that merely melts the Mott correlations. Interestingly, in the fermionized Mott regime, where the density in each well is fragmented, the intra-dimer correlations exhibit unexpected robustness. These findings provide new insights into many-body correlation dynamics and novel localization mechanisms in quasi-periodic lattices, paving the way for engineering exotic quantum behaviors in ultracold atomic systems.
Quantum Gases (cond-mat.quant-gas)
Unifying framework for non-Hermitian and Hermitian topology in driven-dissipative systems
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Clara C. Wanjura, Andreas Nunnenkamp
Recently, a one-to-one correspondence between non-trivial non-Hermitian topology and directional amplification has been demonstrated, theoretically and experimentally, for the case of one complex band. Here, we extend our framework to multiple bands and higher spatial dimension. This proves to be far from trivial. Building on the singular value decomposition, we introduce a new quantity that we dub generalised singular spectrum (GSS). The GSS allows us to define physically meaningful bands related to the system’s scattering behaviour and to define invariants for novel notions of point gaps (non-Hermitian topology) and line gaps (Hermitian-like topology), respectively. For both invariants, we prove a bulk-boundary correspondence and show that they give rise to two different kinds of topological edge modes. We illustrate our results with a 1D non-Hermitian Su-Schrieffer-Heeger (SSH) model and a 2D non-Hermitian model that features corner-to-corner amplification. Our work is relevant for many state-of-the-art experimental platforms and it sets the stage for applications such as novel directional amplifiers and non-reciprocal sensors.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optics (physics.optics), Quantum Physics (quant-ph)
main text: 9 pages, 4 figures. Comments welcome!
Dynamical correlation effects in twisted bilayer graphene under strain and lattice relaxation
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Lorenzo Crippa, Gautam Rai, Dumitru Călugăru, Haoyu Hu, Jonah Herzog-Arbeitman, B. Andrei Bernevig, Roser Valentí, Giorgio Sangiovanni, Tim Wehling
We study the impact of lattice effects due to heterostrain and relaxation on the correlated electron physics of magic-angle twisted bilayer graphene, by applying dynamical mean-field theory to the topological heavy fermion model. Heterostrain is responsible for splitting the 8-fold degenerate flat bands into two 4-fold degenerate subsets, while relaxation breaks the particle-hole symmetry of the unperturbed THF model. The interplay of dynamical correlation effects and lattice symmetry breaking enables us to satisfactorily reproduce a wide set of experimentally observed features: splitting the flat band degeneracy has observable consequences in the form of a filling-independent maximum in the spectral density away from zero bias, which faithfully reproduces scanning tunneling microscopy and quantum twisting microscopy results alike. We also observe an overall reduction in the size and degeneracy of local moments upon lowering the temperature, in agreement with entropy measurements. The absence of particle-hole symmetry has as a consequence the stronger suppression of local moments on the hole-doped side relatively to the electron-doped side, and ultimately causes the differences in existence and stability of the correlated phases for negative and positive doping. Our results show that even fine-level structures in the experimental data can now be faithfully reproduced and understood.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
6 pages, 4 figures plus supplementary material
Quantum Dynamics of Electron Scattering from Skyrmions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Hareram Swain, Arijit Mandal, S. Satpathy, B.R.K. Nanda
Scattering of electrons from chiral spin textures such as the skyrmions is an emerging research area due to its richness in topological quantum transport, which is significant for spintronic devices. We study the dynamical process of scattering of the spin-$ \frac{1}{2}$ particles in the form of Gaussian wavepackets from skyrmions with the aid of the non-relativistic time-dependent Schrödinger equation. The scattering cross section shows a rich angular dependence and is deterministically influenced by the iterative flipping of the spin state inside the skyrmion. The latter leads to a set of non-trivial outcomes which include finite transmission and reflection probabilities irrespective of interaction strength, formation of secondary wavefronts associated with back-converted spin components, and a long-lived quasi-bound state at the scattering center. In addition to the rich and intriguing physics, the numerical recipe developed here can be easily adopted for any arbitrary spin texture, which will prepare a playground to explore tunable spin transport.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
14 pages, 8 figures, 1 table
There and Back Again: A Gauging Nexus between Topological and Fracton Phases
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Pranay Gorantla, Abhinav Prem, Nathanan Tantivasadakarn, Dominic J. Williamson
Coupled layer constructions are a valuable tool for capturing the universal properties of certain interacting quantum phases of matter in terms of the simpler data that characterizes the underlying layers. In the study of fracton phases, the X-Cube model in 3+1D can be realized via such a construction by starting with a stack of 2+1D Toric Codes and turning on a coupling which condenses a composite “particle-string” object. In a recent work [arXiv:2505.13604], we have demonstrated that in fact, the particle-string can be viewed as a symmetry defect of a topological 1-form symmetry. In this paper, we study the result of gauging this symmetry in depth. We unveil a rich gauging web relating the X-Cube model to symmetry protected topological (SPT) phases protected by a mix of subsystem and higher-form symmetries, subsystem symmetry fractionalization in the 3+1D Toric Code, and non-trivial extensions of topological symmetries by subsystem symmetries. Our work emphasizes the importance of topological symmetries in non-topological, geometric phases of matter.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
29 pages, 2 figures, 2 tables
Electrical detection of magnons with nanoscale magnetic tunnel junctions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Christopher Heins, Zeling Xiong, Attila Kákay, Joo-Von Kim, Thibaut Devolder, Aleksandra Titova, Johannes Müller, René Hübner, Andreas Worbs, Ryszard Narkowicz, Jürgen Fassbender, Katrin Schultheiss, Helmut Schultheiss
Present information and communication technologies are largely based on electronic devices, which suffer from heat generation and high power consumption. Alternatives like spintronics and magnonics, which harness the spin degree of freedom, offer compelling pathways to overcome these fundamental limitations of charge-based electronics. Magnonics relies on spin waves, the collective excitations of magnetic moments in magnetically ordered materials, to achieve processing and transport of information at microwave frequencies without relying on charge currents. However, efficient means for all-electrical, high-resolution, semiconductor-compatible readout of information encoded in spin waves are still missing. Here, we demonstrate the electrical detection of spin waves using a nanoscale magnetic tunnel junction (MTJ) cell fabricated in a state-of-the-art complementary metal-oxide-semiconductor (CMOS) production line. By engineering the dynamic coupling between spin waves and the magnetization state of the MTJ, we demonstrate transduction of spin-wave excitations into measurable electrical signals with high fidelity. Moreover, through these measurements, we find spectral line widths, associated with nonlinear processes, down to a few hundreds of kHz, which opens up new perspectives for spin waves as quantum transducers.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Reaction/Diffusion Competition Drives Anomalous Relaxation of Vitrimers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
Makayla R. Branham-Ferrari, Shinian Cheng, Alexei P. Sokolov, David S. Simmons
Vitrimers are an emerging class of crosslinked polymer networks in which dynamic covalent bonds can exchange and rearrange, without any significant change in population of bonded states.1 Because these bonds can rearrange at high temperatures without disintegration of the network, vitrimers could combine the mechanical stability of traditional permanently crosslinked networks with the recyclability of glasses and physical networks. However, unlike classical transient/physical networks, vitrimers can relax at a rate that is decoupled from the mobility of their polymer segments. This challenges our fundamental understanding of how dynamic covalent networks relax and deform. Here we combine simulations, theory, and experiments to show that vitrimer dynamics exhibit two very different regimes: (i) a high temperature regime controlled by the local bond-exchange reaction rate and (ii) a low temperature regime controlled by segmental diffusion. This fundamental difference from traditional physical networks explains why vitrimers can exhibit Arrhenius dynamics, providing a foundation for their rational design.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
Ramp Josephson junctions of Al/Ti/Sr2RuO4: Observation of single-domain quantum oscillations and the detection of chiral edge current
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
Zixuan Li, Yiqun Alex Ying, Brian M. Zakrzewski, Yan Xin, Yu Wang, Zhiqiang Mao, Ying Liu
The spontaneous breaking of time-reversal symmetry (TRS), one of the hallmarks of unconventional superconductivity, has been observed in the superconducting state of Sr2RuO4 by muon spin rotation in several independent studies. However, the chiral edge current expected in such a superconductor has not yet been established experimentally. In addition, the angle dependence of the phase of the superconducting order parameter (OP) in Sr2RuO4, which would enable determination of the full symmetry properties of the OP, has been determined only for a couple of angles. Both issues can be addressed by preparing high-quality Josephson junctions between Sr2RuO4 and a conventional s-wave superconductor with varying orientations relative to the crystal axes. Here we report the successful fabrication of ramp Josephson junctions of Al/Ti/ Sr2RuO4 on thin single crystals of Sr2RuO4 obtained by mechanical exfoliation. These junctions exhibit high-quality quantum oscillations as a function of magnetic field. Moreover, the junction resistance was found to be extremely sensitive to the current flowing in the Sr2RuO4 crystal, a feature that was used in this work to show that the chiral edge current. The approach to the chiral edge current detection, which was not used previously, was verified by a control experiment.
Superconductivity (cond-mat.supr-con)
19 pages, 4 figures
Tunable Electronic Interactions and Weak Antilocalization in Bulk Ge$2$Sb$2$Te${5-5x}$Se${5x}$ Phase Change Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Nicholas Mazzucca, Junjing Zhao, Zhenyang Xu, Despina Louca, Utpal Chatterjee, Marc Bockrath
Phase change materials (PCMs) are well-known for their reversible and rapid switching between crystalline and amorphous phases through thermal excitations mediated by strong electrical or laser pulses. This crystal-to-amorphous transition is accompanied by a remarkable contrast in optical and electronic properties, making PCMs useful in nonvolatile data storage applications. Here, we combine electrical transport and angle resolved photoemission spectroscopy (ARPES) measurements to study the electronic structure of bulk Ge$ _2$ Sb$ _2$ Te$ _{5-5x}$ Se$ _{5x}$ (GSST) for $ 0\le x \le 0.8$ , where $ x$ represents the amount of Se substituting Te in Ge$ _2$ Sb$ _2$ Te$ _5$ (GST)– a prototypical PCM. The single-particle density of states (SDOS) derived from the integrated ARPES data displays metallic behavior for all $ x$ , as evidenced by the presence of a finite density of states in the vicinity of the chemical potential. Transport measurements also display clear signatures of metallic transport, consistent with the SDOS data. The temperature dependence of the resistance indicates the onset of moderate electron-electron Coulomb interaction effects at low temperatures for $ x\geq 0.6$ . At the same time, the magnetoresistance data shows signatures of weak antilocalization for $ x\geq 0.6$ . An analysis on the temperature dependence of the phase coherence length suggests that electron dephasing is primarily due to inelastic electron-electron scattering. We find that these effects are enhanced with increasing $ x$ , portraying GSST as a novel PCM where electronic interactions can be tuned via chemical doping.
Materials Science (cond-mat.mtrl-sci), Disordered Systems and Neural Networks (cond-mat.dis-nn)
Rapid Autotuning of a SiGe Quantum Dot into the Single-Electron Regime with Machine Learning and RF-Reflectometry FPGA-Based Measurements
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Marc-Antoine Roux, Joffrey Rivard, Victor Yon, Alexis Morel, Dominic Leclerc, Claude Rohrbacher, El Bachir Ndiaye, Felice Francesco Tafuri, Brendan Bono, Stefan Kubicek, Roger Loo, Yosuke Shimura, Julien Jussot, Clément Godfrin, Danny Wan, Kristiaan De Greve, Marc-André Tétrault, Dominique Drouin, Christian Lupien, Michel Pioro-Ladrière, Eva Dupont-Ferrier
Spin qubits need to operate within a very precise voltage space around charge state transitions to achieve high-fidelity gates. However, the stability diagrams that allow the identification of the desired charge states are long to acquire. Moreover, the voltage space to search for the desired charge state increases quickly with the number of qubits. Therefore, faster stability diagram acquisitions are needed to scale up a spin qubit quantum processor. Currently, most methods focus on more efficient data sampling. Our approach shows a significant speedup by combining measurement speedup and a reduction in the number of measurements needed to tune a quantum dot device. Using an autotuning algorithm based on a neural network and faster measurements by harnessing the FPGA embedded in Keysight’s Quantum Engineering Toolkit (QET), the measurement time of stability diagrams has been reduced by a factor of 9.8. This led to an acceleration factor of 2.2 for the total initialization time of a SiGe quantum dot into the single-electron regime, which is limited by the Python code execution.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
9 pages, 5 figures
Analytical analysis of the spin wave dispersion in the cycloidal spin structures under the influence of magneto-electric coupling
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Spin waves and coupling of the spin waves with electromagnetic waves are considered in the multiferroic materials with the electric dipole moment proportional to the scalar product of spins. Dispersion dependence for the spin waves propagating as the perturbation of the equilibrium state described by spin cycloid is found. The dielectric permeability as the response on the electromagnetic perturbations associated with the magneto-electric coupling for the same equilibrium state is calculated.
Materials Science (cond-mat.mtrl-sci)
11 pages, 5 figures
Conservative yet constitutively odd elasticity in prestressed metamaterials
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
Tyler A. Engstrom, Daniel M. Sussman
We introduce a design principle for mechanical metamaterials based on “odd elasticity, once removed.” By revisiting classic results relating the variation of Cauchy stress and Lagrangian strain around a prestressed reference state, we show how anisotropic, equilibrium prestress can generate a major anti-symmetry in the material’s constitutive response. Tuning the system to such a state drives it to a critical instability, radically transforming its acoustic properties. We then inverse-design several uniform 2D solids that act as unique waveguides supporting decoupled modes along special lattice directions: a string-like mode and an exotic, in-plane soft mode with a flexural character ($ \omega \sim q^2$ ). The soft modes are insensitive to the value of the anisotropic prestress and exhibit oscillating momentum density but support a non-oscillatory, constant energy current. This principle of harnessing conservative “oddness” to unlock instability-driven wave phenomena provides a powerful new route to creating tunable materials for filtering, guiding, and controlling mechanical waves.
Soft Condensed Matter (cond-mat.soft)
5 pages, 2 figures
Strain-tunable anomalous Hall effect in hexagonal MnTe
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Zhaoyu Liu, Sijie Xu, Jonathan M. DeStefano, Elliott Rosenberg, Tingjun Zhang, Jinyulin Li, Matthew B. Stone, Feng Ye, Rong Cong, Siyu Pan, Ching-Wu Chu, Liangzi Deng, Emilia Morosan, Jiun-Haw Chu, Pengcheng Dai
The ability to control and manipulate time-reversal ($ T$ ) symmetry-breaking phases with near-zero net magnetization is a sought-after goal in spintronic devices. The recently discovered hexagonal altermagnet manganese telluride ($ \alpha$ -MnTe) is a prime example. It has a compensated $ A$ -type antiferromagnetic (AFM) ground state where the in-plane ferromagnetic (FM) moments in each layer are stacked antiferromagnetically along the $ c$ axis, yet exhibits a spontaneous anomalous Hall effect (AHE) that breaks the $ T$ -symmetry with a vanishingly small $ c$ -axis FM moment. However, the presence of three 120$ ^\circ$ separated in-plane magnetic domains presents a challenge in understanding the origin of AHE and the effective control of the altermagnetic state. Here we use neutron scattering to show that a compressive uniaxial strain along the next-nearest-neighbor Mn-Mn bond direction detwins $ \alpha$ -MnTe into a single in-plane magnetic domain, aligning the in-plane moments along the same direction. Furthermore, we find that uniaxial strain (-0.2% to 0.1%) significantly sharpens the magnetic hysteresis loop and switches the sign of the AHE near room temperature. Remarkably, this is achieved without altering the AFM phase-transition temperature, which can only be explained by a strain-induced modification of the electronic band structure. Our work not only unambiguously establishes the relationship between the in-plane moment direction and the AHE in $ \alpha$ -MnTe but also paves the way for future applications in highly scalable, strain-tunable magnetic sensors and spintronic devices.
Strongly Correlated Electrons (cond-mat.str-el)
18 pages, 13 figures
Nonlinear Response Relations and Fluctuation-Response Inequalities for Nonequilibrium Stochastic Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-25 20:00 EDT
Predicting how systems respond to external perturbations far from equilibrium remains a fundamental challenge across physics, chemistry, and biology. We present a unified response framework for stochastic Markov dynamics that integrates linear and nonlinear perturbations. Our formalism expresses nonlinear responses of observables in terms of the covariance between the observable and a nonlinear conjugate variable. The nonlinear conjugate variable is subject to the complete Bell polynomial form and is determined by the stochastic entropy production. In addition, the Fluctuation-Response Inequalities (FRIs) are also derived for nonlinear responses, unraveling the general trade-off relations between nonlinear response and systems’ fluctuations far from equilibrium. The validity of our theory is verified by the numerical results from a symmetric exclusion process (SEP). By unifying and extending nonequilibrium linear response theories, our approach can provide principled design rules for sensitive, adaptive synthetic and biological networks.
Statistical Mechanics (cond-mat.stat-mech)
Knight shift measurements probing Fermi surface changes under pressure in CeRhIn$_5$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Y.-H. Nian, C. Chaffey, P. Sherpa, L. Santillan, K. Nagashima, Peter Klavins, V. Taufour, N. J. Curro
We report nuclear magnetic resonance (NMR) Knight shift measurements of the In(1) and In(2) sites in CeRhIn$ _5$ as a function of pressure. In contrast to the $ c$ axis, the in-plane components of the In(1) Knight shift tensor exhibit little to no pressure dependence. These results indicate that the dipolar component of the tensor is strongly suppressed at the In(1) site, while it remains constant with pressure at the In(2) site. We analyze the hyperfine coupling in terms of a tight binding model for the electronic structure, and determine that the pressure dependence of the In(1) shift cannot be explained in terms of changes to the crystal field parameters, but rather can be understood in terms of an increase in the 4f electron content at the Fermi surface. Our results indicate that the hyperfine coupling reflects changes in the electronic structure near a Kondo breakdown quantum critical point.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 8 figures
Quantum criticality in cuprate superconductors revealed by optical conductivity measurement
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
Hwiwoo Park, Sung-Sik Lee, G. D. Gu, Jungseek Hwang
The ubiquitous temperature ($ T$ )-linear behaviour of the transport scattering rate in the normal state of strongly correlated electron systems is called strange metallicity \cite{zaanen:2004,phillips:2022,hartnoll:2022,chowdhury:2022,yuan:2022}. Although strange metallicity is crucial to understanding superconductivity in correlated electron systems, its origin remains elusive to date \cite{hussey:2023}. Here, we present the doping-, temperature-, and frequency ($ \omega$ )-dependent transport properties of overdoped Bi$ _2$ Sr$ 2$ CaCu$ 2$ O$ {8+\delta}$ in a wide doping range of 0.183 to 0.231. We observe that the optical scattering rate and effective mass exhibit an $ \omega/T$ scaling behaviour at a critical doping of $ p{c} \simeq$ 0.231. Away from the critical doping, the $ \omega/T$ scaling behaviour is destroyed below a doping-dependent crossover temperature $ T\Delta(p) \sim |p-p{c}|^{0.24}$ . Furthermore, the optical coherence mode (OCM) observed within the superconducting dome rapidly broadens and eventually disappears as the critical doping is approached. The emergence of the $ \omega/T$ scaling behaviour of the transport scattering rate and broadening of the OCM near the critical doping strongly suggests that strange metallic behaviour is caused by quantum critical fluctuations. Our results provide compelling spectroscopic evidence for quantum criticality in cuprate superconductors.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
25 pages, 10 figures
Hybridization gap and $f$-electron effect evolutions with Cd- and Sn-doping in CeCoIn$_5$ via infrared spectroscopy
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Myounghoon Lee, Yu-Seong Seo, Seulki Roh, Seokbae Lee, Jihyun Kim, Tuson Park, Jungseek Hwang
We investigated hole (Cd)- and electron (Sn)-doped CeCoIn$ _5$ (CeCo(In$ _{1-x}T_x$ )$ _5$ ($ T$ = Cd or Sn)) using infrared spectroscopy. Doping-dependent hybridization gap distribution functions were obtained from the optical conductivity spectra based on the periodic Anderson model formalism. The hybridization gap distribution exhibits two components: in-plane and out-of-plane hybridization gaps. The doping-dependent evolution of the two gaps indicated that the out-of-plane gap was more sensitive to doping. Furthermore, the magnetic optical resistivity exhibited a doping-dependent evolution of the $ f$ -electron amplitude. The two dopant types exhibited different physical properties depending on the level of doping. The Sn dopant increases the $ f$ -electron amplitude, whereas the Cd dopant does not affect the $ f$ -electron amplitude. Doping-dependent effective mass is peaked at pure (or undoped) CeCoIn$ _5$ . Our spectroscopic results may help understand the doping-dependent electronic evolution of one of the canonical heavy fermion systems, CeCoIn$ _5$ .
Strongly Correlated Electrons (cond-mat.str-el)
19 pages, 8 figures
Physical Review B 109, 125147/1-9 (2024)
Roles of Fe-ion irradiation on MgB$_2$ thin films: Structural, superconducting, and optical properties
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
Dzung T. Tran, Tien Le, Yu-Seong Seo, Duc H. Tran, Tuson Park, Soon-Gil Jung, T. Miyanaga, Chorong Kim, Sunmog Yeo, Won Nam Kang, Jungseek Hwang
The effects of Fe-ion irradiation on the crystal structure and superconducting properties of MgB$ _2$ thin films were investigated. Pristine samples were prepared using hybrid physical-chemical vapor deposition (HPCVD), and ion irradiation was performed at three different doses of 5 x 10$ ^{13}$ , 1 x 10$ ^{14}$ , and 2 x 10$ ^{14}$ ions/cm$ ^2$ . The measured temperature-dependent resistivity showed that as the irradiation dose increased from pristine to most irradiated, the superconducting critical temperature, $ T_c$ , significantly decreased from 38.33 to 3.02 K. The crystal structures of the films were investigated by X-ray diffraction (XRD) and X-ray absorption spectroscopy (XAS) measurements. The results showed that the higher the dose, the greater the change in crystal structure, such as the lattice constant and bond length. This suggests that the destruction of the crystal structure at higher doses leads to the degradation of superconductivity in the irradiated MgB$ _2$ thin films. Raman spectroscopy showed that the electron-phonon coupling constant decreased with increasing irradiation dose, which was directly related to the reduction of $ T_c$ in the samples. The optical conductivity indicates that the charge-carrier density of the $ \sigma$ -band plays an important role in the superconductivity of ion-irradiated MgB$ _2$ .
Superconductivity (cond-mat.supr-con)
28 pages, 8 figures
Journal of Alloys and Compounds 968, 172144/1-8 (2023)
Holographic Aspects of Dynamical Mean-Field Theory
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Kouichi Okunishi, Akihisa Koga
Dynamical mean-field theory (DMFT) is one of the most standard theoretical frameworks for addressing strongly correlated electron systems. Meanwhile, the concept of holography, developed in the field of quantum gravity, provides an intrinsic relationship between quantum many-body systems and space-time geometry. In this study, we demonstrate that these two theories are closely related to each other by shedding light on holographic aspects of DMFT, particularly for electrons with a semicircle density of states. We formulate a holographic renormalization group for the branch Green’s function from the outer edge to the interior of the Bethe lattice network, and then find that its fixed point can be interpreted as a self-consistent solution of Green’s function in DMFT. By introducing an effective two-dimensional anti-de Sitter space, moreover, we clarify that the scaling dimensions for the branch Green’s function and the boundary correlation functions of electrons at the outer edge of the Bethe lattice network are characterized by the fixed-point Green’s function. We also perform DMFT computations for the Bethe-lattice Hubbard model, which illustrate that the scaling dimensions capture the Mott transition in the deep interior.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Lattice (hep-lat), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
16 pages, 5 figures
Harmonic and Subharmonic Magnon Generation in a Surface Acoustic Wave Resonator
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Yunyoung Hwang, Liyang Liao, Jorge Puebla, Marco Brühlmann, Carlos Gonzalez-Ballestero, Kouta Kondou, Naoki Ogawa, Sadamichi Maekawa, Yoshichika Otani
We experimentally observe the generation of magnon harmonics and subharmonics in an on-chip surface acoustic wave resonator incorporating a thin Co$ {20}$ Fe$ {60}$ B$ {20}$ film, using micro-focused Brillouin light scattering. In our devices, rotating the in-plane magnetic field allows continuous tuning of the magnon-phonon coupling from weak to strong within the same resonator. In the weak coupling regime, we only observe fundamental magnetoelastic wave signal at $ f{1}$ . Conversely, in the strong coupling regime, in addition to the fundamental magnetoelastic wave, we observe subharmonic and harmonic signals at $ 3/2f{1}$ , $ 2f{1}$ , and $ 3f_{1}$ , which are well reproduced by our analytical model. Our results establish phonons as a means to generate and control nonlinear magnons in the strong coupling regime, providing a new route for magnonic signal processing.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Other Condensed Matter (cond-mat.other)
5 pages, 4 figures
Projective crystal symmetry and topological phases
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Chen Zhang, Shengyuan A. Yang, Y. X. Zhao
Quantum states naturally represent symmetry groups, though often in a projective sense. Intriguingly, the projective nature of crystalline symmetries has remained underexplored until very recently. A series of groundbreaking theoretical and experimental studies have now brought this to light, demonstrating that projective representations of crystal symmetries lead to remarkable consequences in condensed matter physics and various artificial crystals, particularly in their connection to topological phenomena. In this article, we explain the basic ideas and notions underpinning these recent developments and share our perspective on this emerging research area. We specifically highlight that the appearance of momentum-space nonsymmorphic symmetry is a unique feature of projective crystal symmetry representations. This, in turn, has the profound consequence of reducing the fundamental domain of momentum space to all possible flat compact manifolds, which include torus and Klein bottle in 2D and the ten platycosms in 3D, presenting a significantly richer landscape for topological structures than conventional settings. Finally, the ongoing efforts and promising future research directions are discussed.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 3 figures, to be published in Materials Today Quantum
Domain wall skyrmion-based magnonic crystal
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Zhenyu Wang, Xingen Zheng, Zhixiong Li, Zhizhi Zhang, Xiansi Wang
Magnonic waveguide based on domain wall (DW) is considered as a crucial breakthrough toward the realization of magnonic nanocircuits. However, the effective control of spin waves propagating in DWs remains to be explored. Here, we construct a magnonic crystal (MC) by using a chain of the domain wall skyrmions (DWSKs) to manipulate the spin-wave propagation in DWs. We show that the DWSK chain can be created by leveraging voltage-controlled Dzyaloshinskii-Moriya interaction. The DWSK-based MC opens magnonic bandgaps, which can be dynamically adjusted through magnetic fields modulating the DWSK size. Furthermore, the manipulation of spin waves by the DWSK-based MC maintains robust in curved DW, demonstrating its adaptability to complex device architectures. Our work provides an effective method to control the spin-wave propagation in DWs and paves the way for designing energy-efficient magnonic nanocircuits.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 5figures
A General Many-Body Perturbation Framework for Moiré Systems: Application to Rhombohedral Pentalayer Graphene/hBN Heterostructures
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Xin Lu, Yuanfan Yang, Zhongqing Guo, Jianpeng Liu
Moiré superlattices host a rich variety of correlated topological states, including interaction-driven integer and fractional Chern insulators. A common approach to study interacting ground states at integer fillings is the Hartree-Fock mean-field method. However, this method neglects dynamical correlations, which often leads to an overestimation of spontaneous symmetry breaking and fails to provide quantitative descriptions of single-particle excitations. This work introduces a general many-body perturbation framework for moiré systems, combining all-band Hartree-Fock calculations with random phase approximation (RPA) correlation energies and $ GW$ quasiparticle corrections. We apply this framework to moiré superlattice consisted of rhombohedral pentalayer graphene aligned with hexagonal boron nitride. Our all-band Hartree-Fock calculations, which include all plane-wave components up to the high-energy cutoff of the continuum model, reveal a phase diagram at moiré filling $ \nu=1$ that qualitatively aligns with experimental measurements. Incorporating RPA correlation energy further yields quantitative agreement with the evolution of transport properties across electric fields. The $ GW$ quasiparticle bands exhibit significantly reduced gaps and bandwidths compared to Hartree-Fock results, while quasiparticle weights close to unity indicate that the ground state is well-described by a Slater determinant, justifying the qualitative effectiveness of mean-field approaches for integer fillings in this system. Our versatile framework provides a systematic beyond-mean-field approach applicable to generic moiré systems.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 3 figures, 1 table; supp info will be uploaded soon
Grand thermodynamic potential in a two-band unconventional superconductor
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
V. A. Shestakov, M. M. Korshunov
In a two-band system, both conventional sign-preserving $ s_{++}$ and unconventional sign-changing $ s_{\pm}$ superconducting state may appear at low temperatures. Moreover, they may transform from one to another due to the impurity scattering. To study the details of such a transition here we derive the expression for the Grand thermodynamic potential $ \Omega$ for a two-band model with nonmagnetic impurities considered in a $ \mathcal{T}$ -matrix approximation. For the iron-based materials within the multiband Eliashberg theory, we show that the $ s_{\pm} \to s_{++}$ transition in the vicinity of the Born limit is a first order phase transition.
Superconductivity (cond-mat.supr-con)
9 pages, 3 figures
Intrinsic defect intolerance in the ultra-pure metal PtSn$_4$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Samikshya Sahu, Dong Chen, Niclas Heinsdorf, Ashley N. Warner, Markus Altthaler, Ashutosh K. Singh, Douglas A. Bonn, Sarah A. Burke, Alannah M. Hallas
Ultra-pure materials are highly valued as model systems for the study of intrinsic physics. Frequently, however, the crystal growth of such pristine samples requires significant optimization. PtSn$ _4$ is a rare example of a material that naturally forms with a very low concentration of crystalline defects. Here, we investigate the origin of its low defect levels using a combination of electrical resistivity measurements, computational modeling, and scanning tunneling microscopy imaging. While typical flux-grown crystals of PtSn$ _4$ can have residual resistivity ratios (RRRs) that can exceed 1000, we show that even at the most extreme formation speeds, the RRR cannot be suppressed below 100. This aversion to defect formation extends to both the Pt and Sn sublattices, which contribute with equal weight to the conduction properties. Direct local imaging with scanning tunneling microscopy further substantiates the rarity of point defects, while the prohibitive energetic cost of forming a defect is demonstrated through density functional theory calculations. Taken together, our results establish PtSn$ _4$ as an intrinsically defect-intolerant material, making it an ideal platform to study other properties of interest, including extreme magnetoresistance and topology.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
The orbital-driven topological phase transition and planar Hall responses in ternary tellurides Weyl semi-metals
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Here we study electronic properties of the ternary tellurides TaXTe$ _4$ (X=Rh, Ir) using density functional theory and investigate chiral anomaly mediated planar Hall response from ab initio calculations. We show that TaRhTe$ _4$ is a hybrid Weyl semimetal (WSM), hosting Weyl points (WPs) of both type-I, type-II, while TaIrTe$ _4$ is a type-II WSM as it hosts only type-II WPs with spin-orbit couplings (SOC). All WPs lie in the $ k_z=0$ plane, and remain well-separated in both momentum and energy landscape. We observe long Fermi arcs connecting Weyl nodes of opposite chirality. We report both SOC and orbital driven topological phase transition in ternary tellurides. TaIrTe$ _4$ undergoes topological phase transition under SOC. Whereas orbital driven topological phase transition due to d$ _{xz}$ orbital has been observed in TaRhTe$ _4$ even without SOC. Furthermore, the evolution of the band structures and the annihilation of WPs due to d$ _{xz}$ -Ir/Rh orbitals associated with the phase transitions in TaXTe$ _4$ are also discussed. This systematic study opens new routes for engineering topological materials relying beyond strong SOC and sheds light on the possible role of correlation effects originating from orbital orbital degree of freedoms in tellurides. We further report an enhancement of planar Hall effects due to orbital driven topological phase transition in TaXTe$ _4$ and we make resort to a tight-binding model to correlate the above findings with the effective mass anisotropy in different types of WSMs.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Main text: 10 pages, 6 figures, SM: 8 pages, 10 figures
$\mathbb{Z}_2$ topological invariant in three-dimensional PT- and PC-symmetric class CI band structures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
We construct a previously missing $ \mathbb{Z}_2$ topological invariant for three-dimensional band structures in symmetry class CI defined by parity-time (PT) and parity-particle-hole (PC) symmetries. PT symmetry allows one to define a real Berry connection and, based on the $ \eta$ -invariant, a spin-Chern–Simons (spin-CS) action. We show that PC symmetry quantizes the spin-CS action to $ {0,2\pi}$ with $ 4\pi$ periodicity, thereby yielding a well-defined $ \mathbb{Z}_2$ invariant. This invariant is additive under direct sums of isolated band structures, reduces to a known $ \mathbb{Z}_2$ index when a global Takagi factorization exists, and in general depends on the choice of spin structure. Finally, we demonstrate lattice models in which this newly introduced $ \mathbb{Z}_2$ invariant distinguishes topological phases that cannot be detected by the previously known topological indices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
17 pages
Gauge invariance and hyperforce correlation theory for equilibrium fluid mixtures
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-25 20:00 EDT
Joshua Matthes, Silas Robitschko, Johanna Müller, Sophie Hermann, Florian Sammüller, Matthias Schmidt
We formulate gauge invariance for the equilibrium statistical mechanics of classical multi-component systems. Species-resolved phase space shifting constitutes a gauge transformation which we analyze using Noether’s theorem and shifting differential operators that encapsulate the gauge invariance. The approach yields exact equilibrium sum rules for general mixtures. Species-resolved gauge correlation functions for the force-force and force-gradient pair correlation structure emerge on the two-body level. Exact 3g-sum rules relate these correlation functions to the spatial Hessian of the partial pair distribution functions. General observables are associated with hyperforce densities that measure the covariance of the given observable with the interparticle, external, and diffusive partial force density observables. Exact hyperforce and Lie algebra sum rules interrelate these correlation functions with each other. The practical accessibility of the framework is demonstrated for binary Lennard-Jones mixtures using both adaptive Brownian dynamics and grand canonical Monte Carlo simulations. Specifically, we investigate the force-force pair correlation structure of the Kob-Andersen bulk liquid and we show results for representative hyperforce correlation functions in Wilding et al.’s symmetrical mixture confined between two asymmetric planar parallel walls.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
15 pages, 2 figures
Building cluster systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Classical spin liquids are frustrated magnetic phases characterized by local constraints, flat bands in reciprocal space, and emergent gauge structures with distinctive signatures such as pinch points. These arise generally in \emph{cluster systems}, where spin interactions can be expressed as constraints on clusters of spins. In this work we present the different generic rules allowing to build such cluster systems together with a few tools allowing to quickly characterize it. We show that based on these rules, it is possible to conceive a tunable recipe for generating such models by decorating a parent lattice on its bonds and/or vertices with symmetry-compatible clusters. This approach highlights a key design trade-off: using fewer cluster types increases the number of flat bands and enhances spin-liquid behavior, but produces denser connectivity that is harder to realize experimentally. The framework is highly tunable, extends naturally to two and three dimensions, and provides a versatile toolbox for engineering new classical spin-liquid candidates with targeted features such as higher-rank pinch points or pinch lines.
Strongly Correlated Electrons (cond-mat.str-el)
6 pages, 5 figures, 4 tables
Ab initio investigation on structural stability and phonon-mediated superconductivity in 2D-hydrogenated M2X (M= Mo, V, Zr; X=C, N) MXene monolayer
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
Jakkapat Seeyangnok, Udomsilp Pinsook
We present a comprehensive first-principles study of hydrogenated M2X (M = Mo, V, Zr; X = C, N) MXene monolayers, focusing on their structural stability, electronic properties, and superconducting behavior. Structural optimizations combined with phonon spectra reveal that partial hydrogenation (1H and 2H) is dynamically stable across most compositions, while full hydrogenation (4H) generally induces lattice instabilities. A notable exception is Zr2CH4, which retains dynamical stability even under maximum hydrogen coverage. Electronic structure analysis shows that all hydrogenated MXenes remain metallic, with the Fermi level dominated by transition-metal d orbitals. In Zr2CH4, a Dirac-like band crossing at the Fermi level is observed, which is gapped by spin-orbit coupling (SOC), yielding a finite gap of 0.095 eV. Electron-phonon coupling (EPC) calculations demonstrate that Mo-based MXenes exhibit strong EPC, with coupling constants lambda = 0.95 (Mo2CH), 1.23 (Mo2NH), and 1.55 (Mo2NH2), corresponding to superconducting critical temperatures Tc about 15 to 22 K within the Allen-Dynes framework (mu\ast = 0.10). By contrast, V- and Zr-based MXenes display weak EPC and negligible Tc, with Zr2CH4 being a special case hosting Dirac-like states rather than superconductivity. Our findings highlight hydrogen functionalization as an effective strategy to stabilize MXene monolayers and to tune their low-energy physics, revealing Mo-based nitride MXenes as promising phonon-mediated superconductors, while Zr2CH4 emerges as a candidate for Dirac physics.
Superconductivity (cond-mat.supr-con)
13 Pages, 7 Figures
Theoretical prediction of Structural Stability and Superconductivity in Janus Ti2CSH MXene
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
Jakkapat Seeyangnok, Udomsilp Pinsook
We present a comprehensive first-principles investigation of the structural stability, vibrational characteristics, and superconducting properties of the Janus Ti2CSH monolayer. Janus MXene (JMXene) materials, such as Ti2CSH, have attracted significant attention due to their intrinsic two-dimensional structure and the absence of out-of-plane symmetry, which give rise to novel physical phenomena. Phonon calculations confirm the dynamical stability of the monolayer, while electronic structure and electron-phonon coupling analyses reveal a strong phonon-mediated pairing mechanism. Anisotropic Migdal-Eliashberg theory predicts a single-gap superconducting state, with gap values between 4.29 and 4.71 meV at 10 K and a critical temperature Tc of 22.6 K. These findings establish Ti2CSH as a promising two-dimensional superconductor with potential applications in quantum and nanoscale technologies.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
13 Pages, 7 Figures
Phase Stability and Superconductivity in Hydrogenated and Lithiated Janus GaXS2 (X = Ga, In) Monolayers
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Jakkapat Seeyangnok, Udomsilp Pinsook
Hydrogen and lithium functionalization of two-dimensional (2D) materials offers a promising route to enhance electronic properties and induce superconductivity. Here, we employ first-principles calculations to explore the phase stability and superconducting behavior of hydrogenated and lithiated Janus GaXS2 (X = Ga, In) monolayers. Among Ga2SH, Ga2SLi, GaInSH, and GaInSLi, only the 2H-GaInSLi structure is dynamically, thermally, and mechanically stable, as confirmed by phonon dispersion, ab initio molecular dynamics, and elastic constants. This monolayer adopts a hexagonal lattice, exhibits metallic behavior, and has a negative formation energy, suggesting experimental feasibility. Anisotropic Migdal-Eliashberg analysis reveals phonon-mediated superconductivity with a critical temperature Tc of 4.8 K. Notably, three distinct superconducting gaps emerge, linked to specific atomic orbitals and phonon modes. Electron doping of 0.2 e per cell increases Tc to nearly 6.2 K while maintaining the three-gap character. These results highlight the effectiveness of selective functionalization in engineering superconductivity and identify GaInSLi as a promising platform for next-generation multi-gap 2D superconducting devices.
Materials Science (cond-mat.mtrl-sci)
15 pages, 9 figures
Exploration of Altermagnetism in $\mathrm{RuO_{2}}$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Yu-Xin Li, Yiyuan Chen, Liqing Pan, Shuai Li, Song-Bo Zhang, Hai-Zhou Lu
The fundamental role of magnetic materials in modern science and technology has driven a rapid surge in research on unconventional magnetism in recent years. In particular, altermagnets, which simultaneously exhibit zero net magnetization in real space and anisotropic spin splitting in momentum space, have garnered significant interest for both fundamental physics and technological applications. Among these, $ \mathrm{RuO_{2}}$ stands as the pioneering and most extensively studied altermagnet. While the intrinsic magnetic order of $ \mathrm{RuO_{2}}$ is still a subject of active debate, numerous exotic phenomena characteristic of altermagnetism have been observed in $ \mathrm{RuO_{2}}$ samples. In this review, we explore each facet of the altermagnetism through specific case studies in $ \mathrm{RuO_{2}}$ , systematically surveying its crystal and magnetic structures, electronic band properties, and transport phenomena. We critically assess the debate surrounding the intrinsic magnetism in $ \mathrm{RuO_{2}}$ , incorporating evidence from altermagnetic signatures in transport, as well as contrasting results from magnetic and spectroscopic measurements. Finally, possible future research directions in this field are discussed.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
23 pages, 9 figures, 1 table
Smart copolymer microgels with high volume phase transition temperature: Composition, swelling, and morphology
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
Aditi Gujare, Stefanie Uredat, Jonas Runge, Felix Morgenstern, Domenico Truzzolillo, Thomas Hellweg, Julian Oberdisse
The thermosensitivity and microstructure of microgels made by copolymerizing standard microgel-forming monomers with more hydrophilic comonomers is investigated, with the aim of increasing the volume phase transition temperature (VPTT). We precisely determine the incorporation of N-(hydroxymethyl)acrylamide (HMAM) and purpose-synthesized N-(2-hydroxyisopropyl)acrylamide (HIPAM) into microgels – neither of which forms microgels on its own by precipitation polymerization. The swelling properties and microstructure of the resulting copolymer microgels with N-isopropylacrylamide (NIPAM, LCST ca. 32°C) and N-isopropylmethacrylamide (NIPMAM, LCST ca. 44°C) are then characterized via turbidimetry, DLS, and AFM. At low comonomer contents, all microgel particles exhibit moderate growth in size. Beyond a system-specific threshold, we observe a significant jump in size, and smoother swelling behavior. For NIPAM-HIPAM, the size increase is linked to a strong rise in swelling capacity, and the formation of a thick corona. The effect of the hydrophilic comonomers on the VPTT correlates linearly with their true composition, allowing us to extrapolate the VPTT of hypothetical pure HMAM and HIPAM microgels. This leads to 99°C for HMAM, and 68°C for HIPAM for the respective VPTT. These numbers can be seen as useful indicators of the effect of these monomers on the VPTT in the copolymerized microgels. The observed changes in VPTT, swelling, size, and morphology suggest that high-VPTT microgels possess unique internal molecular composition gradients, likely due to hydrophobic interactions during synthesis. Our results have potential implications for developing temperature-sensitive microgel-based membranes that can self-adapt their permeability at higher operating temperatures in energy applications.
Soft Condensed Matter (cond-mat.soft)
24 pages, 9 figures
Type-II Band Alignment in the $β$-Ga$_2$O$_3$/Rutile GeO$_2$ Heterojunction toward Solar-Blind Photodetection: A first-principles study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Semiconductor heterostructures capable of separating photogenerated electrons and holes have a wide range of optoelectronic applications, including photodetectors, solar cells, and photocatalysts. $ {\beta}$ -Ga$ _2$ O$ _3$ and rutile GeO$ _2$ are both ultrawide-bandgap semiconductors, with bandgaps of 4.85 eV and 4.68 eV, respectively. In this work, we employ first-principles calculations based on density functional theory to investigate the band alignment of the $ {\beta}$ -Ga$ _2$ O$ _3$ /rutile GeO$ _2$ heterojunction and explore the effect of interfacial oxygen vacancy. Calculations using the PBE0 hybrid functional based on an interface model show that a type-II band alignment emerges at the $ {\beta}$ -Ga$ _2$ O$ _3$ /rutile GeO$ _2$ interface, which facilitates the separation of photogenerated carriers. The valence band maximum of $ {\beta}$ -Ga$ _2$ O$ _3$ lies 0.38 eV below that of rutile GeO$ _2$ , and its conduction band minimum lies 0.36 eV below. The presence of interfacial oxygen vacancy in the stable configuration leads to a reduction in the band offset. Our results suggest that the $ {\beta}$ -Ga$ _2$ O$ _3$ /rutile GeO$ _2$ heterojunction holds significant promise for application in strictly solar-blind photodetectors.
Materials Science (cond-mat.mtrl-sci)
Accurate prediction of optical transitions in epitaxial InGaAs/InAlAs asymmetric coupled quantum well structures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Konstantinos Pantzas, Virginie Trinité, Angel Vasanelli, Carlo Sirtori, Grégoire Beaudoin, Isabelle Sagnes, Jean-Luc Reverchon, Gilles Patriarche
Atomically-resolved Z-contrast and strain mappings are used to extract a model of the composition of an InGaAs/InAlAs asymmetric coupled quantum-well structure grown on InP using metal-organic vapor phase epitaxy. The model accounts for grading across the multiple alloy interfaces. The model is used to compute intersubband absorption in the structure. The simulation accurately predicts the experimental absorption spectrum of the structure within only a few meV, an almost ten-fold improvement over simulations using a square-band profile with nominal alloy compositions, and a significant step forward in accurate and predictive simulations of the optical properties epitaxial heterostructures for emission, modulation and detection in mid-infrared.
Materials Science (cond-mat.mtrl-sci)
Efficient Grand Canonical Global Optimization with On-the-fly-trained Machine-learning Interatomic Potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Jon Eunan Quinlivan Dominguez, Mads-Peter Verner Christiansen, Konstantin M. Neyman, Bøjrk Hammer, Albert Bruix
The characterization of nanostructued materials under reactive environments is challenging due to the complexity of the structural motifs involved and their chemical transformations. Global optimization approaches allow predicting stable structures for targeted materials but addressing the configurational and compositional search spaces is both computationally demanding and inefficient, especially when first principles calculations are required. In this work, we implement and evaluate a computationally efficient grand canonical global optimization algorithm able to identify stable structures and chemical states of targeted systems under given reaction conditions (e.g. reactant pressure and temperature). The algorithm leverages an on-the-fly trained machine-learning interatomic potential based on sparse Gaussian Process Regression and the smooth overlap of atomic positions descriptor to reduce the number of first principles energy evaluations carried out during global optimization searches. The \textit{ab initio} thermodynamics framework is incorporated to approximate the Gibbs energy of evaluated candidates, performing environment-aware optimizations over multiple stoichiometries. We demonstrate the computational performance of this approach and its ability to reproduce some literature examples.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
High pressure lattice dynamics study of few layer-$α$-In$_2$Se$_3$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Shiyu Feng, Anurag Ghosh, Gautham Vijayan, Ziyi Xu, Qian Zhang, Elad Koren, Elissaios Stavrou
Few-layer $ \alpha$ -In$ _2$ Se$ _3$ has been studied under pressure using Raman spectroscopy in a diamond anvil cell up to 60 GPa (at room temperature). A combination of AFM and Raman was used to estimate the thickness of the specimens. While few-layer $ \alpha$ -In$ _2$ Se$ _3$ shows identical structural evolution with the one of the bulk powder-like form of $ \alpha$ -In$ _2$ Se$ _3$ ( $ \alpha$ $ \rightarrow$ $ \beta^{‘}$ $ \rightarrow$ IV ), an abrupt $ \beta^{‘}$ $ \rightarrow$ IV phase transition (at 45 GPa) was observed, in contrast with the case of the bulk specimen where the two phases coexist over a wide pressure range. This is attributed to the difference in specimens morphology, $ i.e.$ single crystal and powder in the case of few-layer and bulk $ \alpha$ -In$ _2$ Se$ _3$ , respectively. This study documents the significance of specimens morphology on the observed pressure-induced phase transitions. The methodology developed in this study for performing high-pressure Raman measurements can be applied to other nanodimensional layered materials.
Materials Science (cond-mat.mtrl-sci)
7 pages, 6 figures
Dynamic self-assembly of active particle systems controlled by light fields
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
Sihang Guo, Guangyu Yang, Guoqing Meng, Yingying Wang, Junxing Pan, Jinjun Zhang
Active particle systems are a class of non-equilibrium systems composed of self-propelled Brownian particles; through interactions between particles within the system, a variety of intriguing collective behaviors can emerge. Based on Brownian dynamics simulations, this study investigates the formation and transition mechanisms of ordered structures in active particle systems regulated by light fields. The study reveals that, under light field regulation, active particles undergo large-scale phase separation behavior, forming specific ordered structures and enabling the dynamic transition between multiple ordered structures. This study systematically explores the effects of light fields on this dynamic phase transition and the corresponding regulatory mechanisms. The research findings provide important references for the precise regulation of collective structures in active systems and the fabrication of micro-nano intelligent devices.
Soft Condensed Matter (cond-mat.soft)
Non-ohmic to ohmic crossover in the breakdown of the quantum Hall states in graphene under broadband excitations
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Torsten Röper, Aifei Zhang, Kenji Watanabe, Takashi Taniguchi, Olivier Maillet, François D. Parmentier, Erwann Bocquillon
Graphene, through the coexistence of large cyclotron gaps and small spin and valley gaps, offers the possibility to study the breakdown of the quantum Hall effect across a wide range of energy scales. In this work, we investigate the breakdown of the QHE in high-mobility graphene Corbino devices under broadband excitation ranging from DC up to 10 GHz. We find that the conductance is consistently described by variable range hopping (VRH) and extract the hopping energies from both temperature and field-driven measurements. Using VRH thermometry, we are able to distinguish between a cold and hot electron regime, which are dominated by non-ohmic VRH and Joule heating, respectively. Our results demonstrate that breakdown in the quantum Hall regime of graphene is governed by a crossover from non-ohmic, field-driven VRH to ohmic, Joule-heating-dominated transport.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Main text (6 pages, 4 figures) and Supplementary material
Breakdown of symmetry constraint in Floquet topological superconductor
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Topological superconductor is regarded as an ideal candidate for topological quantum computing due to its ability to simulate the enigmatic Majorana fermions that satisfy non-Abelian statistics. Previous studies revealed that symmetry exerts an unbreakable constraint on the existence, classes, and orders of Majorana modes. It severely limits the controllability and application of Majorana modes. Here, we propose a Floquet-engineering method to break this symmetry-imposed constraint on topological phases. By applying periodic driving on a system belonging to a symmetry class that prohibits the existence of first-order topological phases, we find that rich first-order Majorana modes are created. Interestingly, exotic hybrid-order topological superconductors with coexisting first-order Majorana boundary modes and second-order Majorana corner modes not only in two different quasienergy gaps but also in one single gap are generated at ease by the periodic driving. Refreshing the prevailing understanding of symmetry constraint on topological phases, our result opens an avenue for the creation of exotic topological superconductors without altering symmetries. It greatly expands the scope of the fabricated materials that host topological superconductor.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Other Condensed Matter (cond-mat.other)
Living Droplets with Mesoscale Swimmers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
L. Malik, N. Sharadhi, M. Lamminmäki, R. A. Lara, V. Jokinen, M. Backholm
We study the activity of “living” droplets, which confine 1-6 mesoswimmers in 3D using a superhydrophobic substrate. The swimmers induce oscillations of the droplets at their inherent resonant frequencies, regardless of swimmer size and number. In contrast, the droplet oscillation amplitude is strongly affected by crowding, which we successfully model with a new scaling law and show that crowding reduces the speed of the swimmers. These fundamental living matter physics results reveal mechanisms for bio-inspired droplet actuation with implications for mesoscale robotics, fluidics, and sensing.
Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
A Universal Framework for Controlling Non-Relativistic Spin Splitting
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Aniruddha Ray, Subhadeep Bandyopadhyay, Sayantika Bhowal
Non-relativistic spin splitting in antiferromagnets has recently attracted considerable attention. Here we present a universal framework for controlling such spin splitting by identifying and manipulating the key atomic distortions that govern it through external perturbations. We demonstrate this concept by tuning the spin-splitting energy in three representative materials with diverse symmetries, inversion-symmetric MnF$ _2$ , ferroelectric BaCuF$ _4$ , and LaMnO$ _3$ /RMnO$ _3$ superlattices. Our results emphasize the essential role of higher-order magnetic multipoles and the intrinsic structure-spin correlations in these systems, thereby advancing current efforts to control spin splitting in real materials and motivating future experimental studies.
Materials Science (cond-mat.mtrl-sci)
11 pages, 7 figures
Generalized Li-Haldane Correspondence in Critical Free-Fermion Systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Yuxuan Guo, Sheng Yang, Xue-Jia Yu
Topological phenomena in quantum critical systems have recently attracted growing attention, as they go beyond the traditional paradigms of condensed matter and statistical physics. However, a general framework for identifying such nontrivial phenomena, particularly in higher-dimensional systems, remains insufficiently explored. In this Letter, we propose a universal fingerprint for detecting nontrivial topology in critical free-fermion systems protected by global on-site symmetries. Specifically, we analytically establish an exact relation between the bulk entanglement spectrum and the boundary energy spectrum at topological criticality in arbitrary dimensions, demonstrating that the degeneracy of edge modes can be extracted from the bulk entanglement spectrum. These findings, further supported by numerical simulations of lattice models, provide a universal fingerprint for identifying nontrivial topology in critical free-fermion systems.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech)
14 pages, 6 figures. Any comments and suggestions are welcome!
Resistive switching behaviors in vertically aligned MoS$_2$ films with Cu, Ag, and Au electrodes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Shuei-De Huang, Touko Lehenkari, Topias Järvinen, Seyed Hossein Hosseini-Shokouh, Farzaneh Bouzari, Krisztian Kordas, Hannu-Pekka Komsa
Neuromorphic computing circuits can be realized using memristors based on low-dimensional materials enabling enhanced metal diffusion for resistive switching. Here, we investigate memristive properties of vertically aligned MoS$ _2$ (VA-MoS$ _2$ ) films with three different metal electrodes: Ag, Cu, and Au. Despite having the same active material, all three metals show distinct switching behavior, which are crucial for neuromorphic computing applications: Ag enables volatile switching, Cu demonstrates stable non-volatile switching with retention over 2500 s, and Au shows no memristive response. Cu devices show abrupt resistance changes, and significant increase of copper content upon biasing, indicative of stable non-volatile switching based on filament formation and rupture. About 85% of Ag and Cu devices exhibit reliable memristor behavior. Our findings provide valuable insights into the memristive switching mechanism in VA-MoS$ _2$ and present a promising avenue for facile fabrication of neuromorphic circuits by employing a set of different metals on a single active material.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
23 pages, 4 figures, supporting information
Glassy dynamics in two-dimensional ring polymers: size versus stiffness polydispersity
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
Rahul Nayak, Pinaki Chaudhuri, Satyavani Vemparala
Soft glassy materials often consist of deformable objects. Here, we use a two-dimensional assembly of semi-flexible ring polymers as a model system to investigate how polydispersity in particle stiffness or size influences the onset of glassy dynamics. In simulations at fixed polydispersity 30%, we find that stiffness dispersity drives most rings into elongated conformations at high densities, leading to orientationally ordered structures that cause dynamical slowing down. In contrast, size dispersity generates a bimodal population: small rings remain circular and act as rigid inclusions, while large rings elongate, producing frustration that delays arrest. Real-space maps of bond relaxation reveal strikingly different pathways of dynamical heterogeneity, with long-lived domains persisting under stiffness dispersity but rapidly percolating relaxation under size dispersity. Moreover, local correlations between ring shape, orientational order, and mobility show that stiffness dispersity produces dynamics that are strongly structure-sensitive, whereas size dispersity activates motion from both circular and elongated populations. By linking microscopic deformability to emergent glassy dynamics, this study identifies how the nature of polydispersity controls the relaxation pathways of soft glasses.
Soft Condensed Matter (cond-mat.soft)
12 pages, 7 figures
Hierarchy of timescales in a disordered spin-$1/2$ XX ladder
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-25 20:00 EDT
Kadir Çeven, Lukas Peinemann, Fabian Heidrich-Meisner
Understanding the timescales associated with relaxation to equilibrium in closed quantum many-body systems is one of the central focuses in the study of their non-equilibrium dynamics. At late times, these relaxation processes exhibit universal behavior, emerging from the inherent randomness of chaotic Hamiltonians. In this work, we investigate a disordered spin-$ 1/2$ XX ladder - an experimentally realizable model known for its diffusive dynamics - to explore the connection between transport properties and spectral measures derived solely from the system’s energy levels via these relaxation timescales. We begin by analyzing the spectral form factor, which yields the time when the system begins to follow the random matrix theory (RMT) statistics, known as the RMT time. We then determine the Thouless times - the average times for a local excitation to diffuse across the entire finite system - through the linear-response theory for both spin and energy transport. Our numerical results confirm that the RMT time scales quadratically with system size and upper bounds the Thouless times. Interestingly, we also find that, unlike other non-integrable models, spin diffusion proceeds faster than energy diffusion.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
19 pages, 10 figures
Enhanced White-Light Emission from Self-Trapped Excitons in Antimony and Bismuth Halides through Structural Design
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Philip Klement, Lukas Gümbel, Meng Yang, Jan-Heinrich Littmann, Tatsuhiko Ohto, Hirokazu Tada, Sangam Chatterjee, Johanna Heine
Lead halide perovskites have catalyzed the rise of main-group metal halide materials as promising candidates for next-generation optoelectronics, including solar cells, light-emitting diodes, lasers, sensors, and photocatalysts. Among these, effi-cient light-emission arises from self-trapped excitons, wherein excited states induce transient lattice distortions that localize excitons. However, the complex interplay of factors, such as lattice distortions, lattice softness, and electron-phonon cou-pling dynamics, obscures the direct structure-property relationships complicating the targeted material design. In this study, we advance the understanding of self-trapped exciton (STE)-based emission in hybrid antimony and bismuth halides, em-phasizing the interplay of structural and electronic factors that enhance white-light emission. We systematically vary com-position, anion dimensionality, connectivity, and the organic cation and find that the presence of Bi/Sb and Cl in edge-sharing anion motifs promotes white-light emission and optimal electron-phonon coupling. Chlorides outperform bromides, and organic cations, such as CMA and BZA, only subtly influence optical behavior by altering lattice dynamics and rigidity, resulting in tunable emission characteristics without compromising STEs. This work deepens the understanding of the emis-sion mechanisms in hybrid halide perovskites and establishes guiding principles for tailoring optoelectronic properties, paving the way for advanced materials with enhanced white-light emission for next-generation optoelectronic applications.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
main manuscriot has 13 Pages, 5 figures, 2 tables and supporting information
Quantitative description of the surface tension minimum in a two-component surfactant system
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
The Gibbs adsorption equation is the thermodynamic cornerstone for the description and understanding of the surface tension in a surfactant solution. It relates the decrease in surface tension to an increased surfactant adsorption. In the early 1940’s, it therefore puzzled researchers to sometimes observe a minimum in the surface tension for certain surfactant solutions, which seemed to indicate surfactant desorption (even depletion) according to the Gibbs adsorption equation. It is now understood that the minimum is related to contamination of the surfactant (notably by dodecanol) and its occurrence has since then been studied extensively in experiments. Still, the precise role of the (tiny amount of) contaminant present is not well understood and a quantitative description and understanding of the minimum in the experimental surface tension is lacking. It is the aim of the present article to provide such a quantitative description. Our theoretical analysis is based on a Statistical Thermodynamic treatment of the Langmuir model for a surfactant mixture combined with the mass action model adapted to describe the formation of mixed micelles. A new Statistical Thermodynamic expression for the surface tension is derived and used to compare with a number of surface tension experiments for both ionic and non-ionic surfactant systems.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
34 page, 10 figures; submitted for publication in Langmuir
Multipole analysis of spin currents in altermagnetic MnTe
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Ryosuke Hirakida, Karma Tenzin, Chao Chen Ye, Berkay Kilic, Carmine Autieri, Jagoda Sławińska
Altermagnets, a class of unconventional antiferromagnets where antiparallel spins are connected by combined rotational and translational symmetries, have recently emerged as promising candidates for spintronic applications, as they can efficiently generate spin currents while maintaining vanishing net magnetization. Here, we investigate charge transport and spin currents in $ \alpha$ -MnTe, a prototypical altermagnet, using symmetry analysis within the multipole framework and fully relativistic first-principles calculations using the Kubo formalism. Our results show that different magnetic configurations with Néel vectors $ \hat{N}\parallel y$ and $ \hat{N}\parallel x$ in MnTe induce distinct order parameters. This distinction gives rise to spin-momentum locking with different parities and magnetic spin Hall effects (magnetic SHEs) with different anisotropies. Strikingly, our calculations show that the combination of intrinsic spin-orbit coupling and altermagnetic spin splitting yields a large magnetic spin Hall angle of up to 16 % rivaling or exceeding that of heavy metals such as Pt. On the other hand, the anisotropy of the magnetic SHE provides a practical means to identify the type of order parameter. This establishes, through the powerful framework of multipoles, a general approach for studying transport phenomena that extends to a broader class of altermagnets beyond MnTe.
Materials Science (cond-mat.mtrl-sci)
13 pages, 8 figures
Lateral disorder in Langmuir monolayers: theoretical derivations and grazing-incidence X-ray diffraction
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
L.R. Muftakhova, K.V. Nikolaev, A.V. Rogachev, N.N. Novikova, B.I. Ostrovskii, S.N. Yakunin
Recent studies of the self-assembly of Langmuir monolayers have revealed novel forms of lateral molecular ordering. Such studies typically involve the use of grazing-incidence synchrotron radiation scattering, and the lateral order manifests itself as distinct diffraction patterns. The more intricate the molecular organization, the more complicated the corresponding diffraction pattern is. To the point where standard analysis, i.e., identifying peak positions and solving the crystal structure, is insufficient to describe the system. In such cases, a physics-based simulation of the diffraction is required. In this article, we present a versatile theoretical framework for simulating complex structural molecular ordering in Langmuir monolayers. We begin by applying the formalism to a simple case of solid-state monolayers and extend the analysis to describe the structural organization in the collapsed state. The applicability of the method is validated through comparison with experimental data collected at the bending magnet synchrotron beamline.
Soft Condensed Matter (cond-mat.soft), Disordered Systems and Neural Networks (cond-mat.dis-nn), Computational Physics (physics.comp-ph)
This is an original manuscript consisting of 15 pages and 7 figures. To be submitted for publication in the (IUCr) Journal of Applied Crystallography
Random close packing fraction of bidisperse discs: Theoretical derivation and exact bounds
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
A long-standing problem has been a theoretical prediction of the densest packing fraction of random packings, $ \Phi_{RCP}$ , of same-size discs in $ d=2$ and spheres in $ 3$ . However, to minimize order, experiments and numerical simulations often use two-size discs. For practical purposes, then, a predictive theory for the packing fraction, $ \Phi_{RCP}$ , of the densest such bidisperse packings is more useful. A disorder-guaranteeing theory is formulated here to fill this gap, using an approach that led to an exact solution for monodisperse discs in $ d=2$ [1]. $ \Phi_{RCP}$ depends on the sizes ratio, $ D$ , and concentrations, $ p$ , of the disc types and the developed theory enables derivation of exact and rigorous upper and lower bounds on $ \Phi_{RCP}(p,D)$ , as well as an explicit prediction of it.
Soft Condensed Matter (cond-mat.soft), Disordered Systems and Neural Networks (cond-mat.dis-nn), Mathematical Physics (math-ph)
5 pages, 5 figures
Intrinsic Electro-Optic Kerr Rotation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Erlend Syljuåsen, Alireza Qaiumzadeh, Rembert A. Duine, Arne Brataas
We uncover a previously overlooked contribution to the electro-optic Kerr rotation of reflected light, arising from the interplay of matter, the static electric field, and the magnetic component of light. Remarkably, this mechanism dominates in isotropic nonmagnetic homogeneous metals. We derive analytical expressions for the Kerr rotation in both two-dimensional layers and semi-infinite systems. Within the relaxation-time approximation, we predict experimentally accessible signal magnitudes. This intrinsic mechanism thereby opens new opportunities for probing electronic properties in materials through Kerr spectroscopy.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6+10 pages, 3+2 figures
Single crystal growth, structural and physical properties, and absence of a charge density wave in Ti_{0.85}Fe6Ge6
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Dechao Cheng, Nour Maraytta, Xiuhua Chen, Xizhi Li, Xueliang Wu, Xiangxiang Jing, Yong Hu, Youpin Gong, Mingquan He, Yisheng Chai, Xiaoyuan Zhou, Pengfei Jiang, Yilin Wang, Michael Merz, Aifeng Wang
Kagome materials with charge density waves (CDWs) are fascinating quantum systems, offering an ideal platform to explore intertwined orders and to uncover novel mechanisms behind CDW formation. Chemical models have been developed and applied to predict CDW in $ AM_6X_6$ -type kagome materials, such as the rattling chain model based on ScV6Sn6 and the magnetic energy-saving model based on FeGe. In this study, we successfully synthesized Ti_{0.85}Fe6Ge6 single crystals using the vapor transport method. As predicted by the rattling chain model, these crystals are expected to exhibit kagome CDW behavior. Magnetization measurements indicate that Ti_{0.85}Fe6Ge6 is an easy-axis antiferromagnet with T_N = 488 K and transport measurements reveal metallic behavior primarily driven by electron-type carriers. However, no clear signatures of a CDW were observed in Ti_{0.85}Fe6Ge6. Density functional theory calculations demonstrate a markedly distinct electronic structure compared to related compounds: instead of a carrier-doping-induced rigid shift, the density of states shifted away from the Fermi level. Consistent with our structural investigations, the absence of a CDW and the unusual band structure can be attributed to the bonding characteristic within Ti_{0.85}Fe6Ge6. The strong covalent bonds of Ti-Ge1b, along with the solid Ge1b-Ge1b dimers, prevent the Ti-Ge1b-Ge1b-Ti chain from rattling. The presence of Fe-Fe antibonding state at the Fermi level enhances the spin polarization and depletes the electronic density around the Fermi level. Our results suggest that both the ionic radius and the bonding characteristics of the filler atom are crucial for the formation of CDWs in kagome materials. These factors can serve as supplementary terms to the rattling chain model, providing new insights for the discovery of novel kagome CDW materials.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
12 pages, 8 figures
Unveiling the magnetic behavior of C${\rm3}$N${\rm4}$ 2D material by defect creation, defect passivation, and transition metal adsorption
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Taoufik Sakhraoui, František Karlický
Using the density functional tight binding method (DFTB) and the GFN1-xTB (Geometries, Frequencies, and Noncovalent interactions Tight Binding) Hamiltonian, we have investigated the structural, electronic and magnetic properties of vacancy defects, hydrogen and oxygen passivated defects, and Fe adsorption in two-dimensional (2D) graphitic carbon nitride (gt-C$ _3$ N$ _4$ ) 2D material. The ring shape is the most preferred vacancy evolution path, with significant stability of the semicircle fourfold C-N-C-N vacancy. We found that bare gt-C$ _3$ N$ _4$ which is non-magnetic becomes magnetic by 2-, and 5-defects creation, hydrogen/oxygen passivation of the defects, and upon Fe adsorption. Interestingly, Fe atoms interact with the gt-C$ _3$ N$ _4$ sheet and result in a ground ferromagnetic (FM) state. In addition, we investigate the effects of passivating the vacancies by hydrogen in gt-C$ _3$ N$ _4$ on its structural, electrical, and magnetic properties. We found that substituting the 1, 2, and 3 vacancies with hydrogen and passivating the 6-defect with oxygen turns on magnetism in the system. Due to structural distortion, the passivated defects do not have a well-ordered magnetic orientation. However, passivating the remaining defected structures maintains the nonmagnetic state. It is also shown that passivation leads to a semiconductor with a band gap value higher than that of the bare material. We also calculate the electronic and magnetic properties of transition metal (TM) atoms, including V, Cr, Mn, Fe, Co, Ni-adsorbed gt-C$ _3$ N$ _4$ monolayer. All TM atoms show slight lattice distortion, and the adsorbed system almost maintains the original structure type. Moreover, a FM alignment was observed with a total magnetic moments of 2.89 $ \mu_B$ , 2 $ \mu_B$ , and 1 $ \mu_B$ for V, Fe, and Co atoms, respectively. The Cr, Mn, and Ni atoms induce no magnetism to the non magnetic gt-C$ _3$ N$ _4$ system.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Non-universal localization transition in the quantum Hall effect probed through broken-symmetry states of graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Aifei Zhang, Torsten Röper, Manjari Garg, Kenji Watanabe, Takashi Taniguchi, Carles Altimiras, Patrice Roche, Erwann Bocquillon, Olivier Maillet, François D. Parmentier
The quantum Hall effect hosts quantum phase transitions in which the localization length, that is the size of disorder-induced bulk localized states, is governed by universal scaling from percolation theory. However, this universal character is not systematically observed in experiments, including very recent ones in extremely clean devices. Here we explore this non-universality by systematically measuring the localization length in broken-symmetry quantum Hall states of graphene. Depending on the nature and gap size of these states, we observe differences of up to a tenfold in the minimum localization length, accompanied by clear deviations from universal scaling. Our results, as well as the previously observed non-universality, are fully captured by a simple picture based on the co-existence of localized states from two successive sub-Landau levels.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Massive Discovery of Low-Dimensional Materials from Universal Computational Strategy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Mohammad Bagheri, Ethan Berger, Hannu-Pekka Komsa, Pekka Koskinen
Low-dimensional materials have attractive properties that drive intense efforts for novel materials discovery. However, experiments are tedious for systematic discovery, and present computational methods are often tuned to two-dimensional (2D) materials, overlooking other low-dimensional materials. Here, we combined universal machine-learning interatomic potentials (UMLIPs) and an advanced, interatomic force constant (FC) -based dimensionality classification method to make a massive discovery of novel low-dimensional materials. We first benchmarked UMLIPs’ first-principles-level accuracy in quantifying FCs and calculated phonons for 35,689 materials from the Materials Project database. We then used the FC-based method for dimensionality classification to discover 9139 low-dimensional materials, including 1838 0D clusters, 1760 1D chains, 3057 2D sheets/layers, and 2484 mixed-dimensionality materials, all of which conventional geometric descriptors have not recognized. By calculating the binding energies for the discovered 2D materials, we also identified 960 sheets that could be easily or potentially exfoliated from their parent bulk structures.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
A follow-up on the sulphur atom popping model for MoS$_2$ memristor
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Sanchali Mitra, Santanu Mahapatra
The mechanism of resistive switching in two-dimensional (2D) semiconductor-based memristors is intriguing, and our conventional knowledge of bulk-oxide based memristors does not apply to these devices. Experimental data indicate that the genesis of resistive switching may be intrinsic to the 2D semiconducting active layer, as well as resulting from the movement of electrode atoms. Employing reactive-force field (ReaxFF) molecular dynamics simulations, we introduced the “sulphur atom popping model” [npj 2D Mater. Appl. 5, 33 (2021)] to elucidate the intrinsic nature of non-volatile resistive switching in 2D molybdenum disulfide-based memristors. In this paper we provide additional perspective to this model using density functional theory. We also discuss the limitations of universal machine learning interatomic potentials in reproducing ReaxFF simulation results.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Solution of the Anderson chain with two-particle hybridization of localized and itinerant electrons
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
A modified Anderson lattice is proposed, whose the Hamiltonian accounts for the two-particle hybridization of localized and itinerant electrons instead of one-particle hybridization which takes into account in the original Anderson model. The 1D version of this model can be solved using the Bethe ansazt. It has been shown that hybridization between itinerant and frozen localized electrons results in an effective on-site interaction between itinerant electrons. The magnitude and sign of this interaction depend on the position of the level relative to the Fermi energy (the energy of this level corresponds to the two-particle state of localized electrons at a site). It is shown that when the energy of an localized electron in the two-particle state lies above the Fermi energy, the effective on-site interaction between itinerant electrons is attractive. A repulsive interaction between itinerant electrons occurs when this energy lies below the Fermi energy. Thus, two-part hybridization between localized and itinerant electrons can lead to effective attraction between itinerant electrons, which is unique in itself and may underlie the nature of high-temperature superconductivity.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
10 pages, 1 figure
Random singlet physics in the $S = \frac{1}{2}$ pyrochlore antiferromagnet NaCdCu$_2$F$_7$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Andrej Kancko, Hironori Sakai, Cinthia Antunes Corrêa, Petr Proschek, Jan Prokleška, Tetiana Haidamak, Marc Uhlarz, Adam Berlie, Yo Tokunaga, Ross Harvey Colman
We report a random singlet ground state in the $ S = \frac{1}{2}$ Heisenberg pyrochlore antiferromagnet NaCdCu$ 2$ F$ 7$ . Cationic Na$ ^+$ /Cd$ ^{2+}$ disorder generates a broad distribution of Cu$ ^{2+}$ -F$ ^{-}$ -Cu$ ^{2+}$ exchange couplings. Despite strong antiferromagnetic interactions, no magnetic order or freezing occurs, with $ \mu$ SR measurements confirming dynamics down to 58 mK. $ T$ -linear specific heat, a Curie-like susceptibility tail, and universal power-law scaling with data collapse in $ \chi(T)$ , $ M(H)$ , $ C{\rm mag}/T$ , $ ^{23}$ Na $ (1/T_1T)$ and $ \lambda{\rm LF}$ demonstrate a disorder-driven network of singlets and orphan spins, distinct from a clean quantum spin liquid.
Strongly Correlated Electrons (cond-mat.str-el)
Inelastic scattering and transient localization from coupling to two-level systems
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Hadi Rammal, Sergio Ciuchi, Simone Fratini
We consider an electron interacting locally with two-level systems (TLSs) as an archetypal model for charge transport in the presence of inelastic scatterers. To assess the importance of quantum effects in the optical and d.c. conductivity we solve the model numerically without approximations using the finite temperature Lanczos method (FTLM), and compare the results with Dynamical Mean Field Theory (DMFT). In the slow fluctuation limit, the coupling to the TLSs causes transient localization of the carriers analogous to the one recently found in the electron-boson scattering problem, featuring enhanced resistivities and displaced Drude peaks. Fast inelastic scatterers suppress localization, restoring a more conventional regime where transport and optical properties are governed by independent scattering events.
Strongly Correlated Electrons (cond-mat.str-el)
9 pages, 5 figures including appendices
AMaRaNTA: Automated First-Principles Exchange Parameters In 2D Magnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Federico Orlando (1 and 2), Andrea Droghetti (3 and 2), Lorenzo Varrassi (4), Giuseppe Cuono (2), Cesare Franchini (5 and 4), Paolo Barone (6), Antimo Marrazzo (7), Marco Gibertini (8 and 9), Srdjan Stavrić (10 and 2), Silvia Picozzi (11 and 2) ((1) Physics Department - Politecnico di Milano, Milan, Italy, (2) Consiglio Nazionale delle Ricerche CNR-SPIN, c/o Università degli Studi “G. D’Annunzio”, Chieti, Italy, (3) Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Venice, Italy, (4) Dipartimento di Fisica e Astronomia, Università di Bologna, Bologna, Italy, (5) University of Vienna, Faculty of Physics and Center for Computational Materials Science, Vienna, Austria, (6) Consiglio Nazionale delle Ricerche CNR-SPIN, Area della Ricerca di Tor Vergata, Rome, Italy, (7) Scuola Internazionale Superiore di Studi Avanzati (SISSA), Trieste, Italy, (8) Dipartimento di Scienze Fisiche, Informatiche e Matematiche, Università di Modena e Reggio Emilia, Modena, Italy, (9) Centro S3, Istituto Nanoscienze-CNR, Modena, Italy, (10) Vinča Institute of Nuclear Sciences - National Institute of the Republic of Serbia, University of Belgrade, Belgrade, Serbia, (11) Department of Materials Science, University of Milan - Bicocca, Milan, Italy)
Two-dimensional (2D) magnets host a wide range of exotic magnetic textures, whose low-energy excitations and finite-temperature properties are typically described by effective spin models based on Heisenberg-like Hamiltonians. A key challenge in this framework is the reliable determination, from ab initio calculations, of exchange parameters and their anisotropic components, crucial for stabilising long-range order. Among the different strategies proposed for this task, the energy-mapping method – based on total-energy calculations within Density Functional Theory (DFT) – is the most widely adopted, but it typically requires laborious, multi-step procedures. To overcome this limitation, we introduce AMaRaNTA (Automating Magnetic paRAmeters iN a Tensorial Approach), a computational package that systematically automates the energy-mapping method, specifically through its ``four-state’’ formulation, to extract exchange and anisotropy parameters in 2D magnets. In its current implementation, AMaRaNTA returns the nearest-neighbour exchange tensor, complemented by scalar parameters for second- and third-nearest-neighbour exchange interactions as well as single-ion anisotropy. Together, these provide a minimal yet sufficient set of parameters to capture magnetic frustration and anisotropies, essential for stabilising several observed magnetic states in 2D materials. Applied to a representative subset of the Materials Cloud 2D Structure database, AMaRaNTA demonstrates robust, automated and reproducible screening of magnetic interactions, with clear potential for high-throughput simulations.
Materials Science (cond-mat.mtrl-sci)
13 pages, 5 figures
Effects of correlated hopping on thermoelectric response of a quantum dot strongly coupled to ferromagnetic leads
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-25 20:00 EDT
Kacper Wrześniewski, Ireneusz Weymann
We theoretically investigate the impact of correlated hopping on thermoelectric transport through a quantum dot coupled to ferromagnetic leads. Using the accurate numerical renormalization group method, we analyze the transport characteristics, focusing on the interplay between electronic correlations, spin-dependent transport processes, and thermoelectric response. We calculate the electrical conductance and thermopower as functions of the dot energy level, lead polarization, and the amplitude of correlated hopping. Moreover, we analyze the effect of competing correlations on the Kondo resonance and discuss the asymmetry of conductance peaks under the influence of the exchange field. We demonstrate that the presence of correlated hopping is responsible for asymmetric spin-dependent transport characteristics. Our results provide valuable insight into how correlated hopping affects spin-dependent transport and thermoelectric efficiency in quantum dot systems with ferromagnetic contacts.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Ann. Phys. Vol. 537 (2025)
Climbing the ladder: a method for identifying promising copper-lead apatites
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Ihor Sukhenko, Volodymyr Karbivskyy
We develop a DFT screening procedure for copper-substituted lead apatites of the composition Pb$ _9$ Cu(XO$ _4$ )$ _6$ Y that enforces three design rules: thermodynamic stability, Cu site preference, and symmetry robustness of the near-Fermi electronic structure. A convex-hull analysis over P/V/As as X, O/F/Cl/Br as Y, identifies vanadates as the only members on or beneath the hull. Across the family, Cu substitution at Pb$ ^{\text{I}}$ ($ 4f$ ) preserves flat bands at E$ _F$ , whereas Pb$ ^{\text{I}}$ ($ 6h$ ) either gaps or severely distorts them. Small symmetry-lowering relaxations ($ P3 \rightarrow P1$ ) are also capable of opening the band gap, motivating symmetry robustness as a filter. Applying these criteria singles out Pb$ _9$ Cu(VO$ _4$ )$ _6$ Br$ _2$ (and, possibly, Cl$ _2$ ) as leading candidates. This work motivates experimental study of the selected compounds, as well as a dedicated study of strong correlations.
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 9 figures
Are Neural Networks Collision Resistant?
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-09-25 20:00 EDT
Marco Benedetti, Andrej Bogdanov, Enrico M. Malatesta, Marc Mézard, Gianmarco Perrupato, Alon Rosen, Nikolaj I. Schwartzbach, Riccardo Zecchina
When neural networks are trained to classify a dataset, one finds a set of weights from which the network produces a label for each data point. We study the algorithmic complexity of finding a collision in a single-layer neural net, where a collision is defined as two distinct sets of weights that assign the same labels to all data. For binary perceptrons with oscillating activation functions, we establish the emergence of an overlap gap property in the space of collisions. This is a topological property believed to be a barrier to the performance of efficient algorithms. The hardness is supported by numerical experiments using approximate message passing algorithms, for which the algorithms stop working well below the value predicted by our analysis. Neural networks provide a new category of candidate collision resistant functions, which for some parameter setting depart from constructions based on lattices. Beyond relevance to cryptography, our work uncovers new forms of computational hardness emerging in large neural networks which may be of independent interest.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Cryptography and Security (cs.CR), Probability (math.PR)
31 pages, 12 figures
What causes the variation in superconducting properties of UTe$_{2}$?
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-25 20:00 EDT
C. S. Kengle, Noah Schnitzer, M. M. Bordelon, S. M. Thomas, P. F. S. Rosa
Reaching a consensus on the superconducting order parameter of unconventional superconductors remains a central challenge in the field of magnetically-mediated superconductivity. Though UTe$ _{2}$ is largely accepted as a rare example of an odd-parity superconductor, its precise order parameter remains highly debated, even at ambient conditions. A key underlying issue is the large sample-to-sample variation in superconducting properties at zero applied pressure and magnetic field. Here, we investigate the origin of the observed variation by means of single crystal x-ray diffraction (SC-XRD) and scanning transmission electron microscopy (STEM) measurements. Our results reveal highly ordered crystalline lattices, in agreement with the expected $ Immm$ structure, and no signs of uranium vacancies. Tiny amounts of interstitial defects, however, are observed on the Te2 layers that host Te chains along the b axis. We argue that these defects give rise to slightly enhanced atomic displacement parameters observed in SC-XRD data and are enough to disrupt the unconventional superconducting state in UTe$ _{2}$ . Our findings highlight the need to focus future order parameter determination efforts on single crystals of UTe$ _{2}$ with minimal amounts of structural disorder.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 4 figures
Efficient Microcanonical Histogram Analysis and Application to Peptide Aggregation
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-25 20:00 EDT
A novel approach designed to directly estimate microcanonical quantities from energy histograms is proposed, which enables the immediate systematic identification and classification of phase transitions in physical systems of any size by means of the recently introduced generalized microcanonical inflection-point analysis method. The application to the aggregation problem of GNNQQNY heptapeptides, for which the entire transition sequence is revealed, shows the power of this promising method.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft), Biological Physics (physics.bio-ph)
6 pages, 2 figures
Phys. Rev. Lett. 135, 138401 (2025)
4D-QENS Analysis of Correlated Ionic Conduction in SrCl$_2$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-25 20:00 EDT
Jared Coles, Omar Chmaissem, Matthew Krogstad, Daniel M. Pajerowski, Feng Ye, Duck Young Chung, Mercouri G. Kanatzidis, Stephan Rosenkranz, Raymond Osborn
Methods of elucidating the mechanisms of fast-ion conduction in solid-state materials are pivotal for advancements in energy technologies such as batteries, fuel cells, sensors, and supercapacitors. In this study, we examine the ionic conduction pathways in single crystal SrCl$ _2$ , which is a fast-ion conductor above 900~K, using four-dimensional Quasi-Elastic Neutron Scattering (4D-QENS). We explore both coherent and incoherent neutron scattering at temperatures above the transition temperature into the superionic phase to explore the correlated motion of hopping anions. Refinements of the incoherent QENS yield residence times and jump probabilities between lattice sites in good agreement with previous studies, confirming that ionic hopping along nearest-neighbor directions is the most probable conduction pathway. However, the coherent QENS reveals evidence of de Gennes narrowing, indicating the importance of ionic correlations in the conduction mechanism. This highlights the need for improvements both in the theory of ionic transport in fluorite compounds and the modeling of coherent 4D-QENS in single crystals.
Materials Science (cond-mat.mtrl-sci)
7 pages, 4 figures
Anisotropic shrinkage and finite strains in confined frictional contacts
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-25 20:00 EDT
Marco Ceglie, Cosimo Mandriota, Giuseppe Carbone, Nicola Menga, Antoine Chateauminois
We report on an experimental investigation of the interplay between friction, adhesion, contact geometry, and finite strains for smooth frictional contacts between rigid spherical glass probes and flat silicone substrates. Using both bulk and layer substrates under various loading conditions (normal force, radius of the probe), we show that shear-induced anisotropic shrinkage of the adhesive contact area under steady-state sliding is an effect of finite-elasticity conditions and is drastically affected by the level of geometric confinement. The resulting non-linear coupling between the normal and lateral directions is also investigated measuring the changes in the indentation depth (conv. normal load) during the stiction of the adhesive contacts under imposed normal load (conv. indentation depth) conditions, with strong effects of contact confinement. From a comparison with adhesiveless linear contact mechanics calculations, we show that the experimental observations can only be accounted for by the occurrence of finite strains/displacements conditions. Accordingly, measurements of the in-plane surface displacements at the surface of the rubber substrates confirm that strain levels well in the neo-Hookean range are experienced during steady-state frictional sliding.
Soft Condensed Matter (cond-mat.soft)
Spin-polaron fingerprints in the optical conductivity of iridates
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-25 20:00 EDT
Francesco Cassol, Léo Gaspard, Cyril Martins, Michele Casula, Benjamin Lenz
As a consequence of their spin-orbit entangled ground state, many $ 5d^{5}$ iridate materials display a peculiar double peak structure in optical transport quantities, such as absorption and conductivity. Their common interpretation is based on the presence of Hubbard subbands in the half-filled $ j_{\mathrm{eff}}=1/2$ manifold. Herein, we challenge this picture, proposing a scenario based on the presence of spin-polaron (SP) quasiparticles, and assigning a dominant SP character to the first peak. We illustrate it by taking the materials Ba$ _2$ IrO$ _4$ and Sr$ _2$ IrO$ _4$ as paradigmatic examples, which we investigate within the dynamical mean-field theory and the self-consistent Born approximation. Both theories reproduce nontrivial features revealed by angle-resolved photoemission spectroscopy and optical transport measurements, supporting our interpretation. In the case of Sr$ _2$ IrO$ _4$ , we show how the SP scenario survives in the low-doped regime. Similar optical transport fingerprints are expected to be found in the wider class of $ 5d^5$ iridates and more generally in strongly correlated antiferromagnetic regimes, such as those found in cuprates.
Strongly Correlated Electrons (cond-mat.str-el)
15 pages, 10 figures
Superfluid-Mott transition in a frustrated triangular optical lattice
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-09-25 20:00 EDT
Mehedi Hasan, Luca Donini, Sompob Shanokprasith, Daniel Braund, Tobias Marozsak, Moritz Epping, Daniel Reed, Max Melchner, Tiffany Harte, Ulrich Schneider
Geometric frustration can significantly increase the complexity and richness of many-body physics and, for instance, suppress antiferromagnetic order in quantum magnets. Here, we employ ultracold bosonic $ ^{39}$ K atoms in a triangular optical lattice to study geometric frustration by stabilizing the gas at the frustrated upper band edge using negative absolute temperatures. We find that geometric frustration suppresses the critical interaction strength for the (chiral-)superfluid to Mott insulator ($ \chi$ -SF-MI) quantum phase transition by a factor of 2.7(3) and furthermore changes the critical dynamics of the transition. Although the emergence of coherence during fast ramps from MI to the ($ \chi$ -)SF regime is continuous in both cases, for ramps longer than a few tunnelling times, significant differences emerge. In the \frs case, no long-range order emerges on the studied timescales, highlighting a significantly reduced rate or even saturation of the emerging coherence. This work opens the door to quantum simulations of frustrated systems that are often intractable by classical simulations.
Quantum Gases (cond-mat.quant-gas), Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
7 pages, 4 figures, plus Methods