CMP Journal 2025-10-02
Statistics
Nature Nanotechnology: 1
Nature Physics: 2
Science: 16
Physical Review Letters: 18
Physical Review X: 1
arXiv: 73
Nature Nanotechnology
Convergence of nanotechnology and CRISPR-based diagnostics
Review Paper | Biosensors | 2025-10-01 20:00 EDT
Midori Johnston, Schan Dissanayake-Perera, James J. Collins, Molly M. Stevens, Can Dincer
In addition to its broad application in genome engineering and therapeutics, clustered regularly interspaced short palindromic repeats (CRISPR) technology provides field-deployable methods for the highly sensitive and selective detection of nucleic acids. From a diagnostic perspective, CRISPR-based assays hold clear clinical potential for identifying a range of both infectious and non-communicable diseases. In this Perspective we evaluate recent nanotechnologies and nanomaterials that have been engineered to interface with CRISPR systems on a nanoscale level to realize the full potential of this versatile diagnostic tool. We assess biomolecules such as enzymes and oligonucleotides, some of the more commonly used synthetic nanoparticles and detection platforms that integrate nanotechnologies in new and innovative ways. We discuss current trends and look ahead to future challenges and opportunities, including non-nucleic acid target detection, pre-amplification-free detection of nucleic acids, the development of wearable devices and integration with artificial intelligence workflows.
Biosensors, Microfluidics, Nanoparticles, Nanopores
Nature Physics
Detection and characterization of targets in complex media using fingerprint matrices
Original Paper | Acoustics | 2025-10-01 20:00 EDT
Arthur Le Ber, Antton Goïcoechea, Lukas M. Rachbauer, William Lambert, Xiaoping Jia, Mathias Fink, Arnaud Tourin, Stefan Rotter, Alexandre Aubry
When waves propagate through a complex medium, they undergo several scattering events. This phenomenon is detrimental to imaging, as it causes full blurring of the image. Here we describe a method for detecting, localizing and characterizing any scattering target embedded in a complex medium. We introduce a fingerprint operator that contains the specific signature of the target with respect to its environment. When applied to the recorded reflection matrix, it provides a likelihood index of the target state. This state can be the position of the target for localization purposes, its shape for characterization or any other parameter that influences its response. We demonstrate the versatility of our method by performing proof-of-concept ultrasound experiments on elastic spheres buried inside a strongly scattering granular suspension and on lesion markers, which are commonly used to monitor breast tumours, embedded in a foam mimicking soft tissue. Furthermore, we show how the fingerprint operator can be leveraged to characterize the complex medium itself by mapping the fibre architecture within muscle tissue. Our method is broadly applicable to different types of waves beyond ultrasound for which multi-element technology allows a reflection matrix to be measured.
Acoustics, Imaging techniques
Isospin magnetic texture and intervalley exchange interaction in rhombohedral tetralayer graphene
Original Paper | Electronic properties and devices | 2025-10-01 20:00 EDT
Nadav Auerbach, Surajit Dutta, Matan Uzan, Yaar Vituri, Yaozhang Zhou, Alexander Y. Meltzer, Sameer Grover, Tobias Holder, Peleg Emanuel, Martin E. Huber, Yuri Myasoedov, Kenji Watanabe, Takashi Taniguchi, Yuval Oreg, Erez Berg, Eli Zeldov
The tunable band structure and non-trivial topology of multilayer rhombohedral graphene lead to a variety of correlated electronic states with isospin orders–meaning ordered states in the combined spin and valley degrees of freedom–dictated by the interplay of spin-orbit coupling and Hund’s exchange interactions. However, methods for mapping local isospin textures and determining the exchange energies are currently lacking. Here we image the magnetization textures in tetralayer rhombohedral graphene using a nanoscale superconducting quantum interference device. We observe sharp magnetic phase transitions that indicate spontaneous time-reversal symmetry breaking. In the quarter-metal phase, the spin and orbital moments align closely, providing a bound on the spin-orbit-coupling energy. We also show that the half-metal phase has a very small magnetic anisotropy, which provides an experimental lower bound on the intervalley Hund’s exchange interaction energy. This is found to be close to its theoretical upper bound. The ability to resolve the local isospin texture and the different interaction energies will allow a better understanding of the phase transition hierarchy and the numerous correlated electronic states arising from spontaneous and induced isospin symmetry breaking in graphene heterostructures.
Electronic properties and devices, Magnetic properties and materials
Science
Ancient alleles drive contemporary climate adaptation in an alpine plant
Research Article | Evolution | 2025-10-02 03:00 EDT
Simone Fior, Hirzi Luqman, Mathias Scharmann, Aksel Pålsson, Jennifer de Jonge, Stefan Zoller, Niklaus Zemp, Domenico Gargano, Daniel Wegmann, Alex Widmer
Adaptive evolution is key for species to persist in a warming climate. However, how adaptive genetic variants arise and shape both past and future evolutionary trajectories remains largely unknown. In this work, we integrate genomics with functional and ecological assays to unravel the evolutionary history and adaptive potential of alleles governing adaptation to climate through flowering time in an Alpine carnation. We reveal that “warm” and “cold” alleles of the flowering inhibitor CENTRORADIALIS (DsCEN/2) originated through recombination of highly divergent haplotypes during the carnation radiation, implicating ancestral variation in seeding climate-adaptive alleles. These alleles survived in glacial refugia before mediating the species’ range expansion in response to postglacial warming. We predict that, by recapitulating past evolution, warm alleles will continue to facilitate adaptation under future climate change.
Lithium-ion intercalation by coupled ion-electron transfer
Research Article | Batteries | 2025-10-02 03:00 EDT
Yirui Zhang, Dimitrios Fraggedakis, Tao Gao, Shakul Pathak, Debbie Zhuang, Cristina Grosu, Yash Samantaray, Armando R. C. Neto, Sravani R. Duggirala, Botao Huang, Yun Guang Zhu, Livia Giordano, Ryoichi Tatara, Harsh Agarwal, Ryan M. Stephens, Martin Z. Bazant, Yang Shao-Horn
The underlying reaction mechanism in lithium-ion batteries remains poorly understood. We provide experimental and theoretical evidence that lithium intercalation occurs by coupled ion-electron transfer, where ion transfer across the electrode-electrolyte interface is facilitated by electron transfer to a neighboring redox site. Electrochemical measurements for a variety of common electrode and electrolyte materials reveal a universal dependence of the (de-)intercalation rate on Li+ vacancy fraction, as well as temperature and electrolyte effects consistent with the theory, which could be used to guide the molecular design of lithium-ion battery interfaces.
ATP-dependent remodeling of chromatin condensates reveals distinct mesoscale outcomes
Research Article | Molecular biology | 2025-10-02 03:00 EDT
Camille Moore, Emily Wong, Upneet Kaur, Un Seng Chio, Ziling Zhou, Megan Ostrowski, Ke Wu, Iryna Irkliyenko, Sean Wang, Vijay Ramani, Geeta J. Narlikar
Adenosine triphosphate (ATP)-dependent chromatin remodeling enzymes mobilize nucleosomes, but how such mobilization affects chromatin condensation is unclear. We investigate effects of two major remodelers, ACF and RSC, using chromatin condensates and single-molecule footprinting. We find that both remodelers inhibit the formation of condensed chromatin. However, the remodelers have distinct effects on preformed chromatin condensates. ACF spaces nucleosomes without decondensing the chromatin, explaining how ACF maintains nucleosome organization in transcriptionally repressed genomic regions. By contrast, RSC catalyzes ATP-dependent decondensation of chromatin. RSC also drives micron-scale movements of entire chromatin condensates. These additional activities of RSC may contribute to its central role in transcription. The biological importance of remodelers may thus reflect both their effects on nucleosome mobilization and the corresponding consequences on chromatin dynamics at the mesoscale.
Marine origins and freshwater radiations of the otophysan fishes
Research Article | Fish evolution | 2025-10-02 03:00 EDT
Juan Liu, Donald B. Brinkman, Alison M. Murray, Michael G. Newbrey, Zehua Zhou, Lisa L. Van Loon, Neil R. Banerjee
Otophysans, known for their enhanced hearing enabled by the complex Weberian apparatus, comprise two-thirds of extant freshwater fish species. Previously, they were thought to have originated in fresh water before the breakup of Pangea, implying a nearly 80-million-year gap between the origin and oldest known fossil. However, the discovery of a Late Cretaceous freshwater otophysan challenges this view. Integrating fossil, morphological, and genomic data, we estimate a younger crown group origin of ~154 million years ago. Notably, ancestral range and habitat reconstructions indicate marine origins for the otophysan crown groups, with at least two transitions to fresh water. Functional simulations of the Weberian ossicles of this fossil suggest that the distinctive hearing capabilities of otophysans evolved in conjunction with fusion of hearing ossicle parts and freshwater adaptations.
A comprehensive genetic catalog of human double-strand break repair
Research Article | Molecular biology | 2025-10-02 03:00 EDT
Ernesto López de Alba, Israel Salguero, Daniel Giménez-Llorente, Javier Montes-Torres, Ángel Fernández-Sanromán, Ester Casajús-Pelegay, José Terrón-Bautista, Jonathan Barroso-González, Juan A. Bernal, Geoff Macintyre, Rafael Fernández-Leiro, Ana Losada, Felipe Cortés-Ledesma
The analysis of DNA sequence outcomes provides molecular insights into double-strand break (DSB) repair mechanisms. Using parallel in-pool profiling of Cas9-induced insertions and deletions (indels) within a genome-wide knockout library, we present a comprehensive catalog that assesses the influence of nearly every human gene on DSB repair outcomes. This REPAIRome resource uncovers uncharacterized mechanisms, pathways, and factors involved in DSB repair, including opposing roles for XLF and PAXX, a molecular explanation for Cas9-induced multinucleotide insertions, HLTF functions in Cas9-induced DSB repair, the involvement of the SAGA complex in microhomology-mediated end joining, and an indel mutational signature linked to VHL loss, renal carcinoma, and hypoxia. These results exemplify the potential of REPAIRome to drive future discoveries in DSB repair, CRISPR-Cas gene editing and the etiology of cancer mutational signatures.
Climate-linked escalation of societally disastrous wildfires
Research Article | Wildfires | 2025-10-02 03:00 EDT
Calum X. Cunningham, John T. Abatzoglou, Crystal A. Kolden, Grant J. Williamson, Markus Steuer, David M. J. S. Bowman
Climate change and land mismanagement are creating increasingly fire-prone built and natural environments. However, despite worsening fire seasons, evidence is lacking globally for trends in socially and economically disastrous wildfires, partly due to sparse systematic records. Using a 44-year dataset (1980 to 2023) we analyze the distribution, trends, and climatic conditions connected with the most lethal and costly wildfires. Disastrous wildfires occurred globally over this period but were concentrated in the Mediterranean and temperate conifer biomes. Disaster risk was highest where highly energetic daily fire events intersected affluent, populated areas. Economic disasters increased sharply from 2015 onward, with 43% of the 200 most damaging events occurring in the last decade. Disasters coincided with increasingly extreme climatic conditions, highlighting the urgent need to adapt to a more fire-prone world.
Intercellular communication in the brain through a dendritic nanotubular network
Research Article | Neuroscience | 2025-10-02 03:00 EDT
Minhyeok Chang, Sarah Krüssel, Laxmi Kumar Parajuli, Juhyun Kim, Daniel Lee, Alec Merodio, Jaeyoung Kwon, Shigeo Okabe, Hyung-Bae Kwon
Intercellular nanotubular networks mediate material exchange, but their existence in neurons remains to be explored in detail. We identified long, thin dendritic filopodia forming direct dendrite-dendrite nanotubes (DNTs) in mammalian cortex. Super-resolution microscopy in dissociated neurons revealed DNTs’ actin-rich composition and dynamics, enabling long-range calcium ion (Ca2+) propagation. Imaging and machine learning-based analysis validated in situ DNTs as anatomically distinct from synaptic spines. DNTs actively transported small molecules and human amyloid-β (Aβ); DNT density increased before plaque formation in the medial prefrontal cortex of APP/PS1 mice (APP, Aβ precursor protein; PS1, presenilin-1), suggesting that the dendrite-DNT network might play a role in Alzheimer’s disease pathology. Computational models of DNT-mediated Aβ propagation recapitulated early amyloidosis, predicting selective intracellular accumulation. These findings uncover a nanotubular connectivity layer in the brain, extending neuronal communication beyond classical synapses.
Persistent eastern equatorial Pacific Ocean upwelling since the warm Pliocene
Research Article | Paleoceanography | 2025-10-02 03:00 EDT
Patrick A. Rafter, Jesse R. Farmer, Alfredo Martínez-García, Ana Christina Ravelo, Kristopher B. Karnauskas, Fabian C. Batista, Stefano M. Bernasconi, Haojia Ren, Alexandra Auderset, Gerald H. Haug, Daniel M. Sigman
Upwelling generates a nutrient-rich “cold tongue” in the eastern equatorial Pacific Ocean (EEP), with impacts on global climate, oceanic biological productivity, and the carbon cycle. The cold tongue was reduced during the Pliocene Epoch, a feature attributed to weaker upwelling and an associated deepening of the surface mixed layer in the EEP. Here, we report nitrogen-isotope evidence that modern-like upwelling occurred in the EEP during the Pliocene and has persisted over the past 5 million years. We explain the reduced Pliocene cold tongue as an expression of the reduced temperature difference between surface and subsurface waters in the tropical Pacific. The attendant reduction in the vertical density gradient may have maintained EEP upwelling despite the expected slackening of the trade winds under Pliocene warmth.
GCN1 couples GCN2 to ribosomal state to initiate amino acid response pathway signaling
Research Article | Signal transduction | 2025-10-02 03:00 EDT
Changqian Zhou, Miao Zhang, Jason Murray, Joao Paulo, Steve Gygi, Sichen Shao, Malcolm Whitman, Tracy Keller
During nutrient deprivation, activation of the protein kinase GCN2 regulates cell survival and metabolic homeostasis. In addition to amino acid stress, GCN2 is activated by a variety of cellular stresses. GCN2 activation has been linked to its association with uncharged tRNAs, specific ribosomal proteins, and conditions of translational arrest, but their relative contribution to activation is unclear. Here, we used in vitro translation to reconstitute GCN2 activation by amino acid stress and compared collided ribosome populations induced by diverse translational stressors. Initiation of GCN2 signaling required the di-ribosome sensor GCN1, which recruits GCN2 to ribosomes in a collision-dependent manner, where GCN2 becomes activated by key ribosomal interactions and stably associated with collided ribosomes. Our findings define the molecular requirements and dynamics of GCN2 activation.
Observation of undepleted phosphine in the atmosphere of a low-temperature brown dwarf
Research Article | 2025-10-02 03:00 EDT
Adam J. Burgasser, Eileen C. Gonzales, Samuel A. Beiler, Channon Visscher, Ben Burningham, Gregory N. Mace, Jacqueline K. Faherty, Zenghua Zhang, Clara Sousa-Silva, Nicolas Lodieu, Stanimir A. Metchev, Aaron Meisner, Michael Cushing, Adam C. Schneider, Genaro Suarez, Chih-Chun Hsu, Roman Gerasimov, Christian Aganze, Christopher A. Theissen
The atmospheres of low-temperature brown dwarfs and gas giant planets are expected to contain the phosphine molecule, PH3. However, previous observations have shown much lower abundances of this molecule than predicted by atmospheric chemistry models. We report JWST spectroscopic observations of phosphine in the atmosphere of the brown dwarf Wolf 1130C. Multiple absorption lines due to phosphine are detected around 4.3 μm, from which we calculate a phosphine abundance of 0.100 ± 0.009 parts per million. This abundance is consistent with disequilibrium atmospheric chemistry models that reproduce the phosphine abundances in Jupiter and Saturn, and is much higher than abundances previously reported for other brown dwarfs or exoplanets. This difference may be related to the low abundance of elements heavier than helium in Wolf 1130C.
Localized glutamine leakage drives the spatial structure of root microbial colonization
Research Article | plant science | 2025-10-02 03:00 EDT
Huei-Hsuan Tsai, Yuanjie Tang, Lingmin Jiang, Xiaoyan Xu, Valérie Dénervaud Tendon, Jia Pang, Yanyan Jia, Kathrin Wippel, Jordan Vacheron, Christoph Keel, Tonni Grube Andersen, Niko Geldner, Feng Zhou
Plant roots release exudates to encourage microbiome assembly, which influences the function and stress resilience of plants. How specific exudates drive spatial colonization patterns remains largely unknown. In this study, we demonstrate that endodermal Casparian strips–forming the root’s extracellular diffusion barrier–restrict nutrient leakage into the rhizosphere, coinciding with and controlling spatial colonization patterns of rhizobacteria. We find that vasculature-derived glutamine leakage is a major bacterial chemoattractant and enhancer of proliferation, defining a previously unknown pathway for root exudate formation. Bacteria defective in amino acid chemoperception display reduced attraction toward leakage sites, and roots with Casparian strip defects display bacterial overproliferation, dependent on bacterial capacity for amino acid metabolization. Associated chronic immune stimulation suggests that endodermal nutrient restriction is crucial for regulating microbial colonization and assembly, limiting excessive proliferation that could compromise plant health.
Strengthening nucleic acid biosecurity screening against generative protein design tools
Research Article | Biosecurity | 2025-10-02 03:00 EDT
Bruce J. Wittmann, Tessa Alexanian, Craig Bartling, Jacob Beal, Adam Clore, James Diggans, Kevin Flyangolts, Bryan T. Gemler, Tom Mitchell, Steven T. Murphy, Nicole E. Wheeler, Eric Horvitz
Advances in artificial intelligence (AI)-assisted protein engineering are enabling breakthroughs in the life sciences but also introduce new biosecurity challenges. Synthesis of nucleic acids is a choke point in AI-assisted protein engineering pipelines. Thus, an important focus for efforts to enhance biosecurity given AI-enabled capabilities is bolstering methods used by nucleic acid synthesis providers to screen orders. We evaluated the ability of open-source AI-powered protein design software to create variants of proteins of concern that could evade detection by the biosecurity screening tools used by nucleic acid synthesis providers, identifying a vulnerability where AI-redesigned sequences could not be detected reliably by current tools. In response, we developed and deployed patches, greatly improving detection rates of synthetic homologs more likely to retain wild type-like function.
Two-dimensional diboron trioxide crystal composed by boroxol groups
Research Article | Nanomaterials | 2025-10-02 03:00 EDT
T. Zio, M Dirindin, C. Di Giorgio, M. Thaler, B. Achatz, C. Cepek, I Cojocariu, M. Jugovac, T. O. Menteş, A. Locatelli, L. L. Patera, A. Sala, G. Comelli, M. Peressi, C. Africh
Diboron trioxide (B2O3) represents an unusual case among polymorphic oxides, because its vitrified state features superstructural units–planar boroxol groups–that are never observed in its three-dimensional crystalline polymorphs. Crystalline polymorphs that incorporate boroxol groups have only been predicted theoretically, although their formation is crucial to rationalize the ability of B2O3 to vitrify. Here we present the synthesis of a two-dimensional crystalline B2O3 polymorph constituted by boroxol groups arranged in an atomically thin honeycomb lattice. By combining surface science experimental techniques with ab initio calculations, we characterize the structural and electronic properties of this B2O3 polymorph down to the atomic level. This discovery enlarges the family of two-dimensional materials and enables the atomic tracking of individual structural units in trioxides.
Asynchronous subunit transitions prime acetylcholine receptor activation
Research Article | 2025-10-02 03:00 EDT
Mackenzie J. Thompson, Christian J. G. Tessier, Anna Ananchenko, Camille Hénault, Johnathon R. Emlaw, François Dehez, Eleftherios Zarkadas, Corrie J. B. daCosta, Hugues Nury, John E. Baenziger
Communication at synapses is facilitated by postsynaptic receptors, which convert a chemical signal into an electrical response. For ligand-gated ion channels, agonist binding triggers rapid transitions through intermediate states leading to a transient open-pore conformation, with these transitions shaping the post-synaptic response. Here, we determine structures of the muscle-type nicotinic acetylcholine receptor in unliganded, mono-liganded, and di-liganded states. Agonist binding to a single site stabilizes a closed structure where an entire principal agonist-binding subunit transitions to an active-like conformation, while the other unoccupied principal subunit remains inactive, albeit poised for activation. Uniting this intermediate structure with single-channel recordings informs a sequential activation mechanism where asynchronous subunit transitions prime the receptor for activation, a finding with implications for an entire superfamily of pentameric ligand-gated ion channels.
Engineered geminivirus replicons enable rapid in planta directed evolution
Research Article | 2025-10-02 03:00 EDT
Haocheng Zhu, Xu Qin, Leyan Wei, Dandan Jiang, Qiao Zhang, Wenqian Wang, Ronghong Liang, Rui Zhang, Kang Zhang, Guanwen Liu, Kevin Tianmeng Zhao, Kunling Chen, Jin-Long Qiu, Caixia Gao
Directed evolution can rapidly generate genetic variants with new and enhanced properties, yet efficient platforms for performing such evolution directly in plant cells have been lacking. We developed Geminivirus Replicon-Assisted in Planta Directed Evolution (GRAPE), a system that links gene function to geminivirus rolling circle replication (RCR) to enable high-throughput selection for desired activities. GRAPE supports the screening of up to 105 variants on a single Nicotiana benthamiana leaf within four days. Using GRAPE, we evolved the immune receptor NRC3 to resist inhibition by the nematode effector SPRYSEC15 and broadened the recognition spectrum of the rice immune receptor Pikm-1 to recognize all six alleles of the fungal effector AVR-Pik. GRAPE provides a rapid, scalable, and generalizable platform for directed evolution of diverse genes in plant cellular context.
A high-resolution molecular spin-photon interface at telecommunication wavelengths
Research Article | Quantum optics | 2025-10-02 03:00 EDT
Leah R. Weiss, Grant T. Smith, Ryan A. Murphy, Bahman Golesorkhi, José A. Méndez Méndez, Priya Patel, Jens Niklas, Oleg G. Poluektov, Jeffrey R. Long, David D. Awschalom
Optically addressable electronic spins in polyatomic molecules are a promising platform for quantum information science, with the potential to enable scalable qubit design and integration through atomistic tunability and nanoscale localization. However, optical state- and site-selection are an open challenge. In this work, we introduce an organo-erbium spin qubit in which narrow (megahertz-scale) optical and spin transitions couple to provide high-resolution access to spin degrees of freedom with telecommunication-frequency light. This spin-photon interface enables demonstration of optical spin polarization and readout that distinguishes between spin states and magnetically inequivalent sites in a molecular crystal. Operation at frequencies compatible with mature photonic and microwave devices provides an opportunity for engineering scalable, integrated molecular spin-optical quantum technologies.
Physical Review Letters
Realization of a Fast Triple-Magic All-Optical Qutrit in $^{88}\mathrm{Sr}$
Article | Atomic, Molecular, and Optical Physics | 2025-10-02 06:00 EDT
Maximilian Ammenwerth, Hendrik Timme, Flavien Gyger, Renhao Tao, Immanuel Bloch, and Johannes Zeiher
The optical clock states of alkaline earth and alkaline earthlike atoms are the fundament of state-of-the-art optical atomic clocks. An important prerequisite for the operation of optical clocks is the magic trapping conditions where electronic and motional dynamics decouple. Here, we identify and e…
Phys. Rev. Lett. 135, 143401 (2025)
Atomic, Molecular, and Optical Physics
Heisenberg-Limited Quantum Metrology without Ancillae
Article | Quantum Information, Science, and Technology | 2025-10-01 06:00 EDT
Qiushi Liu and Yuxiang Yang
Extensive research has been dedicated to the asymptotic theory of quantum metrology, where the goal is to determine the ultimate precision limit of quantum channel estimation when many accesses to the channel are allowed. The ultimate limit has been well established, but in general, a noiseless and …
Phys. Rev. Lett. 135, 140801 (2025)
Quantum Information, Science, and Technology
Indefinite Causal Order and Quantum Coordinates
Article | Cosmology, Astrophysics, and Gravitation | 2025-10-01 06:00 EDT
Anne-Catherine de la Hamette, Viktoria Kabel, Marios Christodoulou, and Časlav Brukner
Classically, the causal order of two timelike separated events and is fixed--either before or before . This is no longer true in quantum theory, where it is possible to encounter superpositions of causal orders. The quantum switch is one of the most prominent processes with indefinite caus…
Phys. Rev. Lett. 135, 141402 (2025)
Cosmology, Astrophysics, and Gravitation
Tidal Resonance in Binary Neutron Star Inspirals: A High-Precision Study in Numerical Relativity
Article | Cosmology, Astrophysics, and Gravitation | 2025-10-01 06:00 EDT
Hao-Jui Kuan, Kenta Kiuchi, and Masaru Shibata
We investigate the tidal resonance of the fundamental () mode in spinning neutron stars, robustly tracing the onset of the excitation to its saturation, using numerical relativity for the first time. We performed long-term ( orbits) fully relativistic simulations of a merger of two highly and re…
Phys. Rev. Lett. 135, 141403 (2025)
Cosmology, Astrophysics, and Gravitation
Precision $CP$ Symmetry Test and Polarization Analysis in ${\mathrm{Σ}}^{+}$ Decays
Article | Particles and Fields | 2025-10-01 06:00 EDT
M. Ablikim et al. (BESIII Collaboration)
A stringent test of symmetry in hyperon decays is performed using events and events collected by the BESIII experiment. The asymmetry in the two-body nonleptonic weak decays and is determined to be , consistent…
Phys. Rev. Lett. 135, 141804 (2025)
Particles and Fields
Nanoscale Mirrorless Superradiant Lasing
Article | Atomic, Molecular, and Optical Physics | 2025-10-01 06:00 EDT
Anna Bychek, Raphael Holzinger, and Helmut Ritsch
We predict collective free-space lasing in a dense nanoscopic emitter arrangement where dipole-dipole coupled atomic emitters synchronize their emission and exhibit lasing behavior without the need for an optical resonator. At the example of a subwavelength-spaced linear emitter chain with varying f…
Phys. Rev. Lett. 135, 143601 (2025)
Atomic, Molecular, and Optical Physics
Surface Wave Electron Acceleration from Flat Foils at Parallel Laser Incidence
Article | Plasma and Solar Physics, Accelerators and Beams | 2025-10-01 06:00 EDT
A. McCay, A. McIlvenny, A. Macchi, L. Romagnani, P. Martin, O. Cavanagh, D. P. Molloy, L. Lancia, T. Dzelzainis, H. Ahmed, J. Sarma, S. Kar, D. Margarone, and M. Borghesi
Researchers have shown experimentally that ultraintense lasers can drive high-amplitude surface plasma waves without the need for intricate structures.
Phys. Rev. Lett. 135, 145001 (2025)
Plasma and Solar Physics, Accelerators and Beams
Identification of Gapless Phases by a Twisting Operator
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Hang Su, Tengzhou Zhang, Yuan Yao, and Akira Furusaki
We propose a general necessary condition for a spin chain with SO(3) spin-rotation symmetry to be gapped. Specifically, we prove that the ground state(s) of an SO(3)-symmetric gapped spin chain must be spin singlet(s), and the expectation value of a twisting operator asymptotically approaches unity …
Phys. Rev. Lett. 135, 146502 (2025)
Condensed Matter and Materials
Observation of Anisotropic Dispersive Dark-Exciton Dynamics in CrSBr
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
J. Sears, B. Zager, W. He, C. A. Occhialini, Y. Shen, M. Lajer, J. W. Villanova, T. Berlijn, F. Yakhou-Harris, N. B. Brookes, D. G. Chica, X. Roy, E. Baldini, J. Pelliciari, V. Bisogni, S. Johnston, M. Mitrano, and M. P. M. Dean
Many-body excitons in CrSBr are attracting intense interest in view of their highly anisotropic magneto-optical coupling and their potential for novel optical interfaces within spintronic and magnonic devices. Characterizing the orbital character and propagation of these electronic excitations is cr…
Phys. Rev. Lett. 135, 146503 (2025)
Condensed Matter and Materials
Emergent Inductance from Chiral Orbital Currents in a Bulk Ferrimagnet
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Gang Cao, Hengdi Zhao, Yu Zhang, Alex Fix, Tristan R. Cao, Dhruva Ananth, Yifei Ni, Gabriel Schebel, Rahul Nandkishore, Itamar Kimchi, Hua Chen, Feng Ye, and Lance E. DeLong
We report the discovery of a new form of inductance in the bulk ferrimagnet , which features strong spin-orbit coupling, large magnetic anisotropy, and pronounced magnetoelastic interactions. Below its Curie temperature (), hosts chiral orbital currents (COC) that circulat…
Phys. Rev. Lett. 135, 146504 (2025)
Condensed Matter and Materials
Quantum Anomalous Hall Effects and Emergent SU(2) Hall Ferromagnets at Fractional Filling of Helical Trilayer Graphene
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Sen Niu, Jason Alicea, D. N. Sheng, and Yang Peng
Helical trilayer graphene realizes a versatile moiré system for exploring correlated topological states emerging from high Chern bands. Motivated by recent experimental observations of anomalous Hall effects at fractional fillings of magic-angle helical trilayers, we focus on the higher Chern number…
Phys. Rev. Lett. 135, 146505 (2025)
Condensed Matter and Materials
Dichotomy in Low- and High-Energy Band Renormalizations in Trilayer Nickelate ${\mathrm{La}}{4}{\mathrm{Ni}}{3}{\mathrm{O}}_{10}$: A Comparison with Cuprates
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
X. Du, Y. L. Wang, Y. D. Li, Y. T. Cao, M. X. Zhang, C. Y. Pei, J. M. Yang, W. X. Zhao, K. Y. Zhai, Z. K. Liu, Z. W. Li, J. K. Zhao, Z. T. Liu, D. W. Shen, Z. Li, Y. He, Y. L. Chen, Y. P. Qi, H. J. Guo, and L. X. Yang
Band renormalizations comprise crucial insights for understanding the intricate roles of electron-boson coupling and electron correlation in emergent phenomena such as superconductivity. In this Letter, by combining high-resolution angle-resolved photoemission spectroscopy and theoretical calculatio…
Phys. Rev. Lett. 135, 146506 (2025)
Condensed Matter and Materials
Ultrafast Nonequilibrium Enhancement of Electron-Phonon Interaction in $2{\mathrm{H}\text{-}\mathrm{MoTe}}_{2}$
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Nina Girotto Erhardt, Sotirios Fragkos, Dominique Descamps, Stéphane Petit, Michael Schüler, Dino Novko, and Samuel Beaulieu
Understanding nonequilibrium electron-phonon interactions at the microscopic level and on ultrafast timescales is a central goal of modern condensed matter physics. Combining time- and angle-resolved extreme ultraviolet photoemission spectroscopy with constrained density functional perturbation theo…
Phys. Rev. Lett. 135, 146904 (2025)
Condensed Matter and Materials
Unidirectional Giant Exciton Emission into a Photonic Waveguide
Article | Condensed Matter and Materials | 2025-10-01 06:00 EDT
Qifa Wang, Huan Luo, Chaojie Ma, Bingchang Zhang, Cheng Ji, Qinghong Yu, Guoxiang Chai, Yuxin Li, Chenyang Li, Shaojun Wang, Xuetao Gan, Kaihui Liu, Jianlin Zhao, and Fajun Xiao
Efficient coupling of nanolight sources into photonic waveguides is crucial for integrated photonics, quantum technologies, and biosensing. Practical implementations require light sources with simultaneous high brightness and unidirectional emission. However, it is fundamentally incompatible between…
Phys. Rev. Lett. 135, 146905 (2025)
Condensed Matter and Materials
Walks in Rotation Spaces Return Home when Doubled and Scaled
Article | Statistical Physics; Classical, Nonlinear, and Complex Systems | 2025-10-01 06:00 EDT
Jean-Pierre Eckmann and Tsvi Tlusty
The dynamics of numerous physical systems, such as spins and qubits, can be described as a series of rotation operations, i.e., walks in the manifold of the rotation group. A basic question with practical applications is how likely and under what conditions such walks return to the origin (the ident…
Phys. Rev. Lett. 135, 147201 (2025)
Statistical Physics; Classical, Nonlinear, and Complex Systems
Stopping Cross Sections for Protons Across Different Phases of Water
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-10-01 06:00 EDT
F. Matias, N. E. Koval, P. de Vera, R. Garcia-Molina, I. Abril, J. M. B. Shorto, H. Yoriyaz, J. J. N. Pereira, T. F. Silva, M. H. Tabacniks, M. Vos, and P. L. Grande
A modified DFT method for computing stopping power data across different phases of water shows that liquid water and amorphous ice are indistinguishable in their ability to slow down protons across the relevant energy ranges of medical interest
Phys. Rev. Lett. 135, 148003 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Theory of Reversed Ripening in Active Phase Separating Systems
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-10-01 06:00 EDT
Jonathan Bauermann, Giacomo Bartolucci, Christoph A. Weber, and Frank Jülicher
The ripening dynamics in passive systems is governed by the theory of Lifshitz-Slyosov-Wagner (LSW). Here, we present an analog theory for reversed ripening in active systems. To derive the dynamic theory for the droplet size distribution, we consider a minimal ternary emulsion with one active react…
Phys. Rev. Lett. 135, 148201 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Light-Induced Phase Separation with Finite Wavelength Selection in Photophobic Microalgae
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-10-01 06:00 EDT
Isabelle Eisenmann, Alfredo L’Homme, Aliénor Lahlou, Sandrine Bujaldon, Thomas Le Saux, Benjamin Bailleul, Nicolas Desprat, and Raphaël Jeanneret
As with many motile microalgae, the freshwater species Chlamydomonas reinhardtii can detect light sources and adapt its motile behavior in response. Here, we show that suspensions of photophobic cells can be unstable to density fluctuations, as a consequence of shading interactions mediated by light…
Phys. Rev. Lett. 135, 148401 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Physical Review X
High-Performance and Reliable Probabilistic Ising Machine Based on Simulated Quantum Annealing
Article | | 2025-10-01 06:00 EDT
Eleonora Raimondo, Esteban Garzón, Yixin Shao, Andrea Grimaldi, Stefano Chiappini, Riccardo Tomasello, Noraica Davila-Melendez, Jordan A. Katine, Mario Carpentieri, Massimo Chiappini, Marco Lanuzza, Pedram Khalili Amiri, and Giovanni Finocchio
Simulated quantum annealing enhances probabilistic Ising Machines by enabling faster, more reliable solutions to complex optimization problems using interacting copies of the system guided by a time-dependent field.
Phys. Rev. X 15, 041001 (2025)
arXiv
The Cryogenic Lagrangian Exploration Module: a rotating cryostat for the study of quantum vortices in Helium II via particle seeding
New Submission | Other Condensed Matter (cond-mat.other) | 2025-10-02 20:00 EDT
Jeremy Vessaire, Charles Peretti, Florian Lorin, Emeric Durozoy, Gregory Garde, Panayotis Spathis, Benoit Chabaud, Mathieu Gibert
The study of quantum vortex dynamics in HeII offers great potential for advancing quantum-fluid models. Bose-Einstein condensates, neutron stars, and even superconductors exhibit quantum vortices, whose interactions are crucial for dissipation in these systems. These vortices have quantized velocity circulation around their cores, which, in HeII, are of atomic size. They have been observed indirectly, through methods such as second sound attenuation or electron bubble imprints on photosensitive materials. Over the past twenty years, decorating cryogenic flows with particles has become a powerful approach to studying these vortices. However, recent particle visualization experiments often face challenges with stability, initial conditions, stationarity, and reproducibility. Moreover, most dynamical analyses are performed in 2D, even though many flows are inherently 3D. We constructed a rotating cryostat with optical ports on an elongated square cupola to enable 2D2C, 2D3C, and 3D3C Lagrangian and Eulerian studies of rotating HeII flow. Using this setup, individual quantum vortices have been tracked with micron-sized particles, as demonstrated by Peretti et al., Sci. Adv. 9, eadh2899 (2023). The cryostat and associated equipment -laser, cameras, sensors, and electronics- float on a 50 {\mu}m air cushion, allowing for precise control of the experiment’s physical parameters. The performance during rotation is discussed, along with details on particle injection.
Other Condensed Matter (cond-mat.other), Fluid Dynamics (physics.flu-dyn)
12 pages, 11 figures
Defect mediated quantum melting of charge ordered insulators
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Abijith Krishnan, Ajesh Kumar, T. Senthil
Two-dimensional (2d) electronic systems on a lattice at fractional filling $ \nu = p/q$ exhibit a competition between charge ordered insulators, called Wigner-Mott insulators (WMIs), at large Coulomb repulsion and Fermi-liquid metals at large electronic kinetic energy. When those two energy scales are roughly equal, insulating states that restore the lattice translation symmetry, which we call quantum charge liquids (QCLs), may emerge. When gapped, these QCLs must exhibit topological order. In this work, we show that the allowed topological ordered phases that are proximate to the WMI strongly depend on the charge ordering in the WMI. In particular, we show that when $ q$ is even, no direct transition exists between a WMI with the smallest allowed unit cell size from filling constraints, i.e., the “minimal” WMI, and the topological order with the smallest ground state degeneracy on a torus allowed by filling constraints, i.e., the “minimal” TO. Furthermore, we describe the quantum melting transition of the WMIs to the proximate QCLs in terms of the proliferation of the topological defects of the WMIs. The field theory of this transition in terms of the topological defects reveals their role as precursors to the anyon excitations in the QCLs.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
21 pages, 5 figures
Continuum Fractons: Quantization and the Many Body Problem
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Ylias Sadki, Abhishodh Prakash, S. L. Sondhi
We formulate a continuum quantum mechanics for non-relativistic, dipole-conserving fractons. Imposing symmetries and locality results in novel phenomena absent in ordinary quantum mechanical systems. A single fracton has a vanishing Hamiltonian, and thus its spectrum is entirely composed of zero modes. For the two-body problem, the Hamiltonian is perfectly described by Sturm–Liouville (SL) theory. The effective two-body Hamiltonian is an SL operator on $ (-1,1)$ whose spectral type is set by the edge behavior of the pair inertia function $ K(x)\sim \lvert x -x_\mathrm{edge} \rvert^{\theta}$ . We identify a sharp transition at $ \theta=2$ : for $ \theta<2$ the spectrum is discrete and wavepackets reflect from the edges, whereas for $ \theta>2$ the spectrum is continuous and wavepackets slow down and, dominantly, squeeze into asymptotically narrow regions at the edges. For three particles, the differential operator corresponding to the Hamiltonian is piecewise defined, requiring several “matching conditions” which cannot be analyzed as easily. We proceed with a lattice regularization that preserves dipole conservation, and implicitly selects a particular continuum Hamiltonian that we analyze numerically. We find a spectral transition in the three-body spectrum, and find evidence for quantum analogs of fracton attractors in both eigenstates and in the time evolution of wavepackets. We provide intuition for these results which suggests that the lack of ergodicity of classical continuum fractons will survive their quantization for large systems.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
18 pages, 11 figures
Alloying to Tune the Bandgap of the AM2Pn2 Zintl Compounds
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Andrew Pike, Zhenkun Yuan, Muhammad Rubaiat Hasan, Smitakshi Goswami, Krishanu Samanta, Miguel I. Gonzalez, Jifeng Liu, Kirill Kovnir, Geoffroy Hautier
The AM2Pn2 Zintl compounds are a large class of semiconductor materials that have a wide range of bandgaps and are mostly stable in the same crystal structure. Representative compounds BaCd2P2 and CaZn2P2 have recently been found to exhibit high visible light absorption and long carrier lifetime. Here we use high throughput first-principles calculations to study AM2Pn2 alloys for applications as tandem top cell absorbers (i.e., bandgaps around 1.8 eV) and far infrared detector materials (i.e., bandgaps lower than 0.5 eV). Using a first-principles computational screening workflow for assessing stability and electronic structure of alloys, we identify several promising candidates. These include Ca(Cd0.8Mg0.2)2P2 with a suitable direct bandgap for use in tandem top cells on silicon bottom cells and SrCd2(Sb1-xBix)2 for far infrared detectors. We demonstrate that alloys of AM2Pn2 materials can be realized by experimentally synthesizing Ca(Zn0.8Mg0.2)2P2.
Materials Science (cond-mat.mtrl-sci)
43 pages, 13 figures
Interplay of competing bond-order and loop-current fluctuations as a possible mechanism for superconductivity in kagome metals
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-02 20:00 EDT
Asimpunya Mitra, Daniel J. Schultz, Yong Baek Kim
The pairing symmetry and underlying mechanism for superconducting state of AV$ {}3$ Sb$ {}5$ (A=K, Rb, Cs) kagome metal has been a topic of intense investigation. In this work, we consider an 8-band minimal model, which includes V, and the two types of Sb, both within and above/below the kagome plane. This model captures the Fermi surface pocket with significant in-plane Sb contribution near the zone center, and also has the two types of van Hove singularities (VHS), one of which has a strong out of plane Sb weight. By including V-V and V-planar Sb nearest-neighbor Coulomb interactions, we obtain the susceptibilities for fluctuating bond-order and loop-current in both charge and spin channels, and examine the resulting superconducting instabilities. In particular, we find that the time-reversal odd (even) charge-loop-current (charge bond-order) fluctuations favor unconventional (conventional) pairing symmetry such as $ s{+-}$ and $ d+id$ ($ s{++}$ ). Recent experimental works have highlighted the presence of $ s$ -wave pairing with two distinct gaps, one isotropic and one anisotropic. We discuss how this scenario may be compatible with either $ s_{++}$ or $ s_{+-}$ pairing, with an isotropic gap on the pocket dominated by in-plane Sb, but a highly anisotropic gap on V-dominated bands.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
10+18 pages
Anomalous diffusion in multichannel systems without a Lévy distribution of disorder
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Hazan Ozkan, Stephan Roche, Haldun Sevincli
We show that multichannel quantum systems with uncorrelated but asymmetric Anderson-type disorder can exhibit anomalous diffusion, even in the absence of heavy-tailed disorder. Using a minimal two-channel model with channel asymmetry, we demonstrate a crossover from normal to anomalous transport tuned by interchannel coupling. Applied to quasi-one-dimensional lattices with edge disorder, this leads to long-tailed transmission statistics characterized by ballistic segments interspersed with localized ones, reminiscent of Lévy flights. This channel-asymmetric anomalous diffusion (CAAD) emerges from quantum interference between channels with differing disorder strengths. While CAAD governs transport at intermediate lengths, conventional localization prevails asymptotically, violating the Thouless relation. These results highlight a distinct quantum mechanism for anomalous diffusion beyond classical paradigms.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Supplemental material attched
A Kokkos-Accelerated Moment Tensor Potential Implementation for LAMMPS
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Zijian Meng, Karim Zongo, Edmanuel Torres, Christopher Maxwell, Ryan Eric Grant, Laurent Karim Béland
We present a Kokkos-accelerated implementation of the Moment Tensor Potential (MTP) for LAMMPS, designed to improve both computational performance and portability across CPUs and GPUs. This package introduces an optimized CPU variant–achieving up to 2x speedups over existing implementations–and two new GPU variants: a thread-parallel version for large-scale simulations and a block-parallel version optimized for smaller systems. It supports three core functionalities: standard inference, configuration-mode active learning, and neighborhood-mode active learning. Benchmarks and case studies demonstrate efficient scaling to million-atom systems, substantially extending accessible length and time scales while preserving the MTP’s near-quantum accuracy and native support for uncertainty quantification.
Materials Science (cond-mat.mtrl-sci)
16 pages, 6 figures Software Repository: this https URL
Influence of edge Laser-Induced Periodic Surface Structures (LIPSS) on the electrical properties of fs laser-machined ITO microcircuits
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
A. Frechilla, E. Martínez, J. del Moral, C. López-Santos, J. Frechilla, F. Nuñez-Gálvez, V. López-Flores, G.F. de la Fuente, D. Hülagü, J. Bonse, A. R. González-Elipe, A. Borrás, L.A. Angurel
Scalable and cost-effective methods for processing transparent electrodes at the microscale are transversal for advancing in electrochemistry, optoelectronics, microfluidics, and energy harvesting. In these fields, the precise fabrication of micrometric circuits plays a critical role in determining device performance and integration with added-value substrates. In this context, Laser Subtractive Manufacturing stands out among microfabrication techniques for its adaptability to diverse materials and complex configurations, as well as its straightforward scalability and affordability nature. However, a challenge in micromachining metals and metal oxides is the inherent formation of LIPSS, which can significantly impair electrical conductivity, particularly when circuit dimensions fall within the micrometer range. Herein, we investigate the micromachining of TCOs using ultrashort pulse laser systems applied to ITO thin films. We analyze the formation of LIPSS at the edges of the micromachined regions associated with the Gaussian distribution of the energy within the laser spot and their impact on the electrical properties depending on the circuit characteristics. Thus, we evaluate the influence of LIPSS orientation and periodicity by fabricating various circuit patterns using femtosecond lasers at green (515 nm) and ultraviolet (343 nm) wavelengths. A correlation between electrical resistivity measurements and structural analysis reveals distinct effects of nanostructure formation depending on the laser source. For green wavelength, the regions where LIPSS are oriented perpendicular to the ITO track exhibit higher resistance, by a factor just above two, compared to those where LIPSS are parallel. Additionally, UV laser processing results in a pronounced reduction of ITO thickness at the boundary between the LIPSS region and the substrate.
Materials Science (cond-mat.mtrl-sci)
Bidirectional ultrafast control of charge density waves via phase competition
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Honglie Ning, Kyoung Hun Oh, Yifan Su, Zhengyan Darius Shi, Dong Wu, Qiaomei Liu, B. Q. Lv, Alfred Zong, Gyeongbo Kang, Hyeongi Choi, Hyun-Woo J. Kim, Seunghyeok Ha, Jaehwon Kim, Suchismita Sarker, Jacob P. C. Ruff, B. J. Kim, N. L. Wang, Todadri Senthil, Hoyoung Jang, Nuh Gedik
The intricate competition between coexisting charge density waves (CDWs) can lead to rich phenomena, offering unique opportunities for phase manipulation through electromagnetic stimuli. Leveraging time-resolved X-ray diffraction, we demonstrate ultrafast control of a CDW in EuTe$ _4$ upon optical excitation. At low excitation intensities, the amplitude of one of the coexisting CDW orders increases at the expense of the competing CDW, whereas at high intensities, it exhibits a nonmonotonic temporal evolution characterized by both enhancement and reduction. This transient bidirectional controllability, tunable by adjusting photo-excitation intensity, arises from the interplay between optical quenching and phase-competition-induced enhancement. Our findings, supported by phenomenological time-dependent Ginzburg-Landau theory simulations, not only clarify the relationship between the two CDWs in EuTe$ _4$ , but also highlight the versatility of optical control over order parameters enabled by phase competition.
Strongly Correlated Electrons (cond-mat.str-el)
8 pages, 4 figures
Nonvolatile Switching of Magnetism via Gate-Induced Sliding in Tetralayer Graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Daniel Brandon, Tixuan Tan, Yiwen Ai, Peter Golemis, Akshat Gandhi, Lujin Min, Kenji Watanabe, Takashi Taniguchi, Trithep Devakul, Kenji Yasuda
Interlayer sliding degrees of freedom often determine the physical properties of two-dimensional (2D) materials. In graphene, for instance, the metastable rhombohedral stacking arrangement hosts correlated and topological electronic phases, which are absent in conventional Bernal stacking. Here, we demonstrate a sliding-induced first-order structural phase transition between Bernal and rhombohedral tetralayer graphene driven by gate voltages. Through transport measurement, we observe bistable switching between a Bernal-dominant state and a rhombohedral-Bernal mixed state across a wide space of the gate-voltage phase diagram. The structural phase transition results in nonvolatile switching between a paramagnet and a ferromagnet accompanied by the anomalous Hall effect. The sign reversal of the anomalous Hall effect under opposite displacement fields suggests that it may originate from domain boundaries between the Bernal and rhombohedral regions. Our discovery paves the way for on-demand toggling of quantum phases based on the sliding phase transition of 2D materials and offers a playground to explore unconventional physics at the stacking domain boundaries.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Search for Active and Inactive Ion Insertion Sites in Organic Crystalline Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Harshan Reddy Gopidi, Alae Eddine Lakraychi, Abhishek A. Panchal, Yiming Chen, V. S. Chaitanya Kolluru, Jiaqi Wang, Ying Chen, Liu Jue, Kamila Wiaderek, Maria K.Y. Chan, Yan Yao, Pieremanuele Canepa
The position of mobile active and inactive ions, specifically ion insertion sites, within organic crystals, significantly affects the properties of organic materials used for energy storage and ionic transport. Identifying the positions of these atom (and ion) sites in an organic crystal is difficult, especially when the element has a low X-ray scattering power, such as lithium (Li) and hydrogen, which are difficult to detect with powder X-ray diffraction (XRD) methods. First-principles calculations, exemplified by density functional theory (DFT), are very effective for confirming the relative stability of ion positions in materials. However, the lack of effective strategies to identify ion sites in these organic crystalline frameworks renders this task extremely challenging. This work presents two algorithms: (i) Efficient Location of Ion Insertion Sites from Extrema in electrostatic local potential and charge density (ELIISE), and (ii) ElectRostatic InsertioN (ERIN), which leverage charge density and electrostatic potential fields accessed from first-principles calculations, combined with the Simultaneous Ion Insertion and Evaluation (SIIE) workflow –that inserts all ions simultaneously– to determine ion positions in organic crystals. We demonstrate that these methods accurately reproduce known ion positions in 16 organic materials and also identify previously overlooked low-energy sites in tetralithium 2,6-naphthalenedicarboxylate (Li$ _4$ NDC), an organic electrode material, highlighting the importance of inserting all ions simultaneously as done in the SIIE workflow.
Materials Science (cond-mat.mtrl-sci)
Dimerization in the SU(4) Heisenberg model on the cubic lattice: iPEPS study
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
We study SU(4)-symmetric Heisenberg model on the cubic lattice with spatially anisotropic magnetic couplings. We utilize several approaches based on the tensor-network representation of the many-body wave functions, which enable accurate analysis of ground-state properties of the model in different regimes of spatial anisotropy including fully isotropic three-dimensional case. Our results point to the persistence of the dimerized color-ordered phase throughout whole range of magnetic couplings excluding only the limit of completely decoupled one-dimensional chains.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas)
9 pages, 7 figures
Gate-tunable Josephson parametric amplifiers based on semiconductor nanowires
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Raphael Rousset-Zenou, Nicolas Aparicio, Simon Messelot, Rasmus D. Schlosser, Martin Bjergfelt, Julien Renard, Moïra Hocevar, Jesper Nygård
Superconductor-semiconductor hybrid materials have been extensively used for experiments on electrically tunable quantum devices. Notably, Josephson junctions utilizing nanowire weak links have enabled a number of new gate-tunable qubits, including gatemons, Andreev level qubits and spin qubits. Conversely, superconducting parametric amplifiers based on Josephson junctions have not yet been implemented using nanowires, even though such nearly quantum limited amplifiers are key elements in experiments on quantum circuits. Here we present Josephson parametric amplifiers based on arrays of parallel InAs nanowires that feature a large critical current as required for linear amplification. The resonance frequency of the devices is gate-tunable by almost 1 GHz, with a gain exceeding 20 dB in multiple frequencies and noise approaching the quantum-limit. This new platform enables on-chip integration of gate-tunable qubits with quantum limited amplifiers using the same hybrid materials and on any substrate.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
9+9 pages, 12 figures
Magneto-Tunable Thermal Diode Based on Bulk Superconductor
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-02 20:00 EDT
Poonam Rani, Masayuki Mashiko, Keisuke Hirata, Ken-ichi Uchida, Yoshikazu Mizuguchi
Thermal diode is a growing technology and important for active thermal flow control. Since the theoretical designing of thermal diode in 2004, various kinds of solid-state thermal diodes have been theoretically and experimentally investigated. Here, we report on the observation of thermal rectification in bulk-size superconductor-normal metal junctions. High-purity (5N) wires of Pb and Al are soldered, and thermal conductivity (\k{appa}) of the junctions is measured in two different directions of the heat flow, forward (\k{appa}F) and reverse (\k{appa}R) directions. Thermal rectification ratio (\k{appa}F / \k{appa}R) of 1.75 is obtained at T ~ 5.2 K with H = 400 Oe. The merit of the Pb-Al junction is a large difference of \k{appa} in an order of several hundred W m-1 K-1 and magneto-tunability of the working temperature.
Superconductivity (cond-mat.supr-con)
A poor man’s theory of circular dichroism in single-wall carbon nanotubes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
The theory of circular dichroism in single-wall carbon nanotubes derived within the tight-binding method by a complicated approach in previous work is rederived in a straightforward way using the multipolar expansion of the light-matter interaction.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Template-free precision synthesis of biphilic microdome arrays
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-02 20:00 EDT
Haobo Xu, Haonian Shu, Rong Yang
Biphilic microdome arrays are ubiquitous in nature, but their synthetic counterparts have been scarce. To bridge that gap, we leverage condensed droplet polymerization (CDP) to enable their template-free synthesis. During CDP, monomer droplets serve as microreactors for free-radical polymerization. The droplet diameter is monitored in real time. To enable the precise prediction of the convex geometric parameters, we develop a theoretical framework that integrates geometric arguments, scaling analysis, and kinetic theories. The model accurately predicts the dimensions of the as-synthesized microdome arrays, pointing to unprecedented precision in the synthesis of such topography. To illustrate its impact, the methodology is used to enable biphilic microdomes with targeted dimensions, for the reduction of surface colonization by a biofilm-forming pathogen, Pseudomonas aeruginosa. Importantly, the reduction is achieved with a moderately hydrophobic surface that has been considered prone to fouling, pointing to a fresh material design strategy and broadened palette of synthetic surfaces.
Soft Condensed Matter (cond-mat.soft), Chemical Physics (physics.chem-ph)
25 pages, 9 figures
Anomalous low-field magnetoresistance in Fe$_3$Ga$_4$ single crystals
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Michelle E. Jamer, Gregory M. Stephen, Brandon Wilfong, Radhika Barua, Frank M. Abel, Steven P. Bennett, Joseph C. Prestigiacomo, Don Heiman, Dave Graf
Fe$ _3$ Ga$ _4$ possesses a helical spin spiral with a complex competition between ferromagnetic and antiferromagnetic ground states. This competition generates multiple metamagnetic transitions that are governed by both applied magnetic field and temperature. At intermediate temperatures between T$ _1$ (68 K) and T$ _2$ (360 K), the ferromagnetically aligned spins transition to an antiferromagnetic spin spiral. In this study, magnetoresistance (MR) measurements are performed on an aligned single crystal and compared to magnetization properties in order to gain insight on the unique alignment of the spins. The high-field MR is positive at low temperatures indicating cyclotronic behavior and negative at high temperature from electron-magnon scattering. Of particular significance is a large anomalous positive MR at low fields, possibly due to emergent spin fluctuations thus prompting further exploration of this multifaceted material.
Materials Science (cond-mat.mtrl-sci)
Metallic Oxides and the Overlooked Role of Bandwidth
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Aurland K. Watkins, Anthony K. Cheetham, Ram Seshadri
Oxides exhibiting metallic conduction are crucial for various applications, including fuel cells, battery electrodes, resistive and magnetoresistive materials, electrocatalysts, transparent conductors, and high-temperature superconductors. Oxides that approach metallicity also play significant roles in switching applications, where the metal-insulator transition phenomenon is utilized across a range of technologies. This perspective, motivated by the question of when oxides are metallic, employs electronic structure calculations on metallic oxides to identify the typical feature in the electronic structures that promote metallic behavior. The critical factor of the bandwidth of the electronic energy bands near the Fermi energy is emphasized since it has been somewhat overlooked in the literature. For example, bandwidth considerations would suggest that the recently proposed phosphate “LK-99” would never be a suitable target for superconductivity. From the analysis performed here, we learn that if the width of the conduction band as obtained from density functional theory-based electronic structure calculations is less than 1 eV, then the likelihood of obtaining a metallic compound is vanishingly small. This survey of representative oxide metals highlights the essential elements of extended covalency that lead to wide bands. A key takeaway is that oxyanion compounds such as borates, carbonates, silicates, sulfates, nitrates, and phosphates are unlikely to exhibit metallic conduction at ambient pressure. While the focus here is on oxides, the general findings should apply across various material families, extending to organic crystals, polymers, and framework materials.
Materials Science (cond-mat.mtrl-sci)
41 pages, 11 figures
Microscopic origin of the magnetic easy-axis switching in Fe3GaTe2 under pressure
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Jiaqi Li, Shuyuan Liu, Chongze Wang, Fengzhu Ren, Bing Wang, Jun-Hyung Cho
The two-dimensional layered ferromagnet Fe3GaTe2, composed of a Te-FeI-FeII/Ga-FeI-Te stacking sequence, hosts two inequivalent Fe sites and exhibits a high Curie temperature and strong out-of-plane magneticanisotropy, making it a promising platform for spintronic applications. Recent experiments have observed a pressure-induced switching of the magnetic easy axis from out-of-plane to in-plane near 10 GPa, though its microscopic origin remains unclear. Here, we employ first-principles calculations to investigate the pressure dependence of the magnetocrystalline anisotropy energy in Fe3GaTe2. Our results reveal a clear easy-axis switching at a critical pressure of approximately 10 GPa, accompanied by a sharp decrease in the magnetic moments arising from FeI and FeII atoms. As pressure increases, spin-up and spin-down bands broaden and shift oppositely due to band dispersion effects, leading to a reduction in net magnetization. Simultaneously, the SOC contribution from FeI, which initially favors an out-of-plane easy axis, diminishes and ultimately changes sign, thereby promoting in-plane anisotropy. The SOC contribution from the outer-layer Te atoms also decreases steadily with pressure, although it retains its original sign; this additional reduction further reinforces the in-plane magnetic easy axis. In contrast, FeII atoms continue to favor an out-of-plane orientation, but their contribution is insufficient to counterbalance the dominant in-plane preference at high pressure. These findings elucidate the origin of magnetic easy-axis switching in Fe3GaTe2 and provide insights for tuning magnetic anisotropy in layered materials for spintronic applications.
Materials Science (cond-mat.mtrl-sci)
Possibility of ferro-octupolar order in Ba$_2$CaOsO$_6$ assessed by X-ray magnetic dichroism measurements
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Goro Shibata, Naomi Kawamura, Jun Okamoto, Arata Tanaka, Hiroaki Hayashi, Kazunari Yamaura, Hsiao-Yu Huang, Amol Singh, Chien-Te Chen, Di-Jing Huang, Sergey V. Streltsov, Atsushi Fujimori
Localized $ 5d^2$ electrons in a cubic crystal field possess multipoles such as electric quadrupoles and magnetic octupoles. We studied the cubic double perovskite Ba$ _2$ CaOsO$ _6$ containing the Os$ ^{6+}$ ($ 5d^2$ ) ions, which exhibits a phase transition to a hidden order' below $ T^\ast \sim$ 50 K, by X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) at the Os $ L_{2,3}$ edge. The cubic ligand-field splitting between the $ t_{2g}$ and $ e_g$ levels of Os $ 5d$ was deduced by XAS to be $ \sim$ 4 eV. The temperature dependence of the XMCD spectra was consistent with a $ \sim$ 18 meV residual cubic splitting of the lowest $ J_{\rm eff} =$ 2 multiplet state into the non-Kramers $ E_g$ doublet ground state and the $ T_{2g}$ triplet excited state. Ligand-field (LF) multiplet calculation under fictitious strong magnetic fields indicated that the exchange interaction between nearest-neighbor octupoles should be as strong as $ \sim$ 1.5 meV if a ferro-octupole order is stabilized in the hidden-ordered’ state, consistent with the exchange interaction of $ \sim$ 1 meV previously predicted theoretically using model and density functional theory calculations.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
6 pages, 4 figures
Electrotoroidicity: New Paradigm for Transverse Electromagnetic Responses
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Kai Du, Daegeun Jo, Xianghan Xu, Fei-Ting Huang, Ming-Hao Lee, Ming-Wen Chu, Kefeng Wang, David Vanderbilt, Hyun-Woo Lee, Sang-Wook Cheong
The exploration of transverse electromagnetic responses in solids with broken spatial-inversion (I) and/or time-reversal (T) symmetries has unveiled numerous captivating phenomena, including the (anomalous) Hall effect, Faraday rotations, non-reciprocal directional dichroism, and off-diagonal linear magnetoelectricity, all within the framework of magnetotoroidicity. Here, we introduce a novel class of transverse electromagnetic responses originating from electrotoroidicity in ferro-rotational (FR) systems with preserved I and T symmetries, distinct from magnetotoroidicity. We discover a high-order off-diagonal magnetic susceptibility of FR domains and a reduced linear diagonal magnetic susceptibility at FR domain walls in doped ilmenite FeTiO3. The non-trivial “Hall-like” effect of the former corresponds to an anomalous transverse susceptibility in the presence of spontaneous electrotoroidal moments in FR materials. Our findings unveil an emergent type of transverse electromagnetic responses even in I and T symmetry-conserved conditions and illustrate new functionalities of abundant FR materials.
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other)
Atomic networks as highways for holes in oxygen-deficient amorphous oxides
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Rafael Costa-Amaral, Yu Kumagai
Oxygen-deficient amorphous tellurium oxides ($ a$ -TeO$ _x$ ) have recently challenged the intrinsic hole mobility limits of amorphous oxides, with thin-film transistors reaching mobilities up to 15 cm$ ^{2}$ V$ ^{-1}$ s$ ^{-1}$ upon Se doping. However, the atomistic origins of this behavior, and its seeming contradiction with established semiconductor physics, have remained unresolved. Here, we combine machine-learning-accelerated ab initio molecular dynamics with hybrid-functional defect calculations to establish a new microscopic picture. We show that substantial oxygen loss drives spontaneous segregation into interpenetrating $ a$ -Te and $ a$ -TeO$ _2$ domains, rather than forming dispersed oxygen vacancies. The diffuse Te-$ 5p$ states from the $ a$ -Te network supply percolative pathways for holes, so mobility rises monotonically with oxygen deficiency, enabling mobilities that exceed current records. Doped Se incorporates into the $ a$ -Te domain, enhancing the connectivity of conductive pathways, thereby increasing hole mobility. Similar behavior in amorphous SeO$ _x$ suggests domain percolation as a general route to high-mobility p-type transport in amorphous oxides.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Orbital Altermagnetism
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Mingxiang Pan, Feng Liu, Huaqing Huang
We introduce the concept of \emph{orbital altermagnetism}, a symmetry-protected magnetic order of pure orbital degrees of freedom. It is characterized with ordered anti-parallel orbital magnetic moments in real space but momentum-dependent orbital band splittings, analogous to spin altermagnetism. Using a minimal tight-binding model with complex hoppings in a square-kagome lattice, we show that such order inherently arises from staggered loop currents, producing a $ d$ -wave-like orbital-momentum locking. First-principles calculations show that orbital altermagnetism emerges independent of spin ordering in in-plane ferromagnets of CuBr$ _2$ and VS$ _2$ , so that it can be unambiguously identified experimentally. On the other hand, it may also coexist with spin altermagnetism, such as in monolayer MoO and CrO. The orbital altermagnetism offers an alternative platform for symmetry-driven magnetotransport and orbital-based spintronics, as exemplified by large nonlinear current-induced orbital magnetization.
Materials Science (cond-mat.mtrl-sci)
16 Page, 9 Figures
Machine Learning Prediction of Charged Defect Formation Energies from Crystal Structures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Shin Kiyohara, Chisa Shibui, Soungmin Bae, Yu Kumagai
Recent advances in materials informatics have expanded the number of synthesizable materials. However, screening promising candidates, such as semiconductors, based on defect properties remains challenging. This is primarily due to the lack of a general framework for predicting defect formation energies in multiple charge states from structural data. In this Letter, we present a protocol, namely data normalization, Fermi level alignment, and treatment of perturbed host states, and validate it by accurately predicting oxygen vacancy formation energies in three charge states using a single model. We also introduce a joint machine-learning model that integrates defect formation energies and band-edge predictions for virtual screening. Using this framework, we identify 89 hole-dopable oxides, including BaGaSbO, a potential ambipolar photovoltaic material. Our protocol is expected to become a standard approach for machine-learning studies on point defect formation energies.
Materials Science (cond-mat.mtrl-sci)
submitted
FourPhonon_GPU: A GPU-accelerated framework for calculating phonon scattering rates and thermal conductivity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Ziqi Guo, Xiulin Ruan, Guang Lin
Accurately predicting phonon scattering is crucial for understanding thermal transport properties. However, the computational cost of such calculations, especially for four-phonon scattering, can often be more prohibitive when large number of phonon branches and scattering processes are involved. In this work, we present FourPhonon_GPU, a GPU-accelerated framework for three-phonon and four-phonon scattering rate calculations based on the FourPhonon package. By leveraging OpenACC and adopting a heterogeneous CPU-GPU computing strategy, we efficiently offload massive, parallelizable tasks to the GPU while using the CPU for process enumeration and control-heavy operations. Our approach achieves over 25x acceleration for the scattering rate computation step and over 10x total runtime speedup without sacrificing accuracy. Benchmarking on various GPU architectures confirms the method’s scalability and highlights the importance of aligning parallelization strategies with hardware capabilities. This work provides an efficient and accurate computational tool for phonon transport modeling and opens pathways for accelerated materials discovery.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Excitons and Optical Response in Excitonic Insulator Candidate TiSe$_2$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
The origin of the charge density wave (CDW) phase in TiSe$ _2$ is a highly debated topic, with lattice and excitonic correlations proposed as the main driving mechanisms. One of the proposed scenarios is the excitonic insulator (EI) mechanism, where soft electronic mode drives the phase transition. However, the existence of this purely electronic mode is controversial. Here, we perform fully ab-initio calculations of the electron excitation spectra in TiSe$ 2$ with electron-hole excitonic effects included via Bethe-Salpeter equations. In the normal high-temperature phase the excitation spectra is dominated by the exciton mode at 1.6 eV, while no well-defined soft electronic modes that could support the EI phase are present. In the CDW phase, the structural distortions induce a CDW band-gap opening between Ti-$ d$ and Se-$ p$ states, which supports the formation of the two low-energy excitonic modes in the optical spectrum at 0.4 eV and 80 meV. Close to the transition temperature $ T{\rm CDW}$ , these two excitonic modes are softened and approach zero energy. These results suggest that the EI mechanism is not a main driving force in the formation of the CDW phase in TiSe$ 2$ , but there is a region in the phase diagram near $ T{\rm CDW}$ where EI fluctuations could be relevant.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
6 pages, 2 figures; Comments are welcome
Thermoelectric Enhancement via Electronic and Phononic Channels in Staggered and Non-Staggered Dimerized Quantum Ring
New Submission | Other Condensed Matter (cond-mat.other) | 2025-10-02 20:00 EDT
Ranjini Bhattacharya, Souvik Roy
Harnessing the quantum coherence and tunability of molecular-scale structures, we theoretically explore thermoelectric transport in ring-shaped molecular junctions featuring dimerized hopping integrals. By engineering alternating strong and weak bonds in both staggered and non-staggered configurations, we reveal a marked transmission asymmetry that drives a substantial enhancement in the thermoelectric figure of merit, ZT. To further steer transport behavior, we introduce controlled aperiodicity via site-energy modulations in unit cell format governed by the Aubry-André-Harper (AAH) potential, a quasiperiodic landscape that enables tunable localization-delocalization transitions. This interplay between hopping dimerization and AAH-type disorder gives rise to energy filtering effects and a rich spectrum where extended and critical states coexist, amplifying the Seebeck coefficient while preserving finite electrical conductance. Through a comprehensive non-equilibrium Green’s function analysis, we uncover how key device parameters, including disorder strength, dimerization amplitude, and lead-ring connectivity, collectively shape transport characteristics. Notably, asymmetric lead couplings are shown to enhance performance by leveraging quantum interference pathways. Our findings highlight a robust design strategy for optimizing nanoscale thermoelectric functionality, providing actionable insights for experimental realization in molecular electronic platforms.
Other Condensed Matter (cond-mat.other)
16 pages, 15 figures
Field-free Superconducting Diode Effect in FeTe${0.55}$Se${0.45}$
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-02 20:00 EDT
Peng Dong, Jinghui Wang, Yanjiang Wang, Jianjun Xiao, Xiang Zhou, Hui Xing, Yueshen Wu, Yulin Chen, Jinsheng Wen, Jun Li
The superconducting diode effect (SDE) - the asymmetry of critical currents with respect to current direction - is a pivotal advancement in non-reciprocal superconductivity. While SDE has been realized in diverse systems, a fundamental challenge remains achieving field-free operation in iron-based superconductors with simple device geometries. Here, we report a non-volatile, field-free SDE in thin crystalline FeTe$ _{0.55}$ Se$ _{0.45}$ (FTS), showing asymmetric critical currents with a rectification coefficient of 1.9% and operating temperatures up to 9 K. Intriguingly, a pronounced non-zero second harmonic resistance emerges at the superconducting transition, exhibiting a sign reversal under varying current and temperature. The SDE persists at zero magnetic field and the rectification coefficient($ \eta$ ) exhibits an even symmetric dependence on the magnetic field, distinguishing it from magnetic chirality anisotropy mechanisms. In addition to this, we systematically ruled out influences from dynamic superconducting domains, thermal gradients, and sample geometry, while establishing that localized stress amplifies the rectification coefficient, likely constituting one of the principal contributing factors. These results establish FTS as a robust platform for realizing field-free superconducting diodes in a structurally simple platform.
Superconductivity (cond-mat.supr-con)
Transition between 2D Symmetry Protected Topological Phases on a Klein Bottle
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Vibhu Ravindran, Bowen Yang, Xie Chen
Manifolds with nontrivial topology play an essential role in the study of topological phases of matter. In this paper, we study the nontrivial symmetry response of the $ 2+1$ D $ Z_2$ symmetry-protected topological (SPT) phase when the system is put on a non-orientable manifold – the Klein bottle. In particular, we find that when a symmetry defect is inserted along the orientation-reserving cycle of the Klein bottle, the ground state of the system gets an extra charge. This response remains well defined at transition points into the trivial SPT phase, resulting in an exact two-fold degeneracy in the ground state independent of the system size. We demonstrate the symmetry response using exactly solvable lattice models of the SPT phase, as well as numerical work across the transition. We explore the connection of this result to the modular transformation of the $ 3+1$ D $ Z_2$ gauge theory and the emergent nature of the parity symmetry in the $ Z_2$ SPT phase.
Strongly Correlated Electrons (cond-mat.str-el)
21 pages, 17 figures
Large superconducting diode effect driven by edge states in twisted iron-chalcogenide Josephson junctions
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-02 20:00 EDT
Xiangyu Zeng, Renjie Zhang, Guoliang Guo, Zhuoqing Gao, Quanxin Hu, Haijiao Ji, Fazhi Yang, Xiaozhi Wang, Bo Gao, Noah F. Q. Yuan, Baiqing Lv, Xin Liu, Hong Ding
The superconducting diode effect (SDE)-the unidirectional, dissipationless flow of supercurrent-is a critical element for future superconducting electronics. Achieving high efficiency under zero magnetic field is a key requirement. The Josephson junction constitutes a versatile SDE platform for exploiting quantum materials that exhibit ferromagnetism, topology, or unconventional superconductivity. However, a single two-dimensional material system that inherently offers these properties and allows for precise interface engineering, such as twisting, remains elusive. Here we report a record-high, field-free diode efficiency of ~30% in twist van der Waals Josephson heterostructures of the sign-change iron-chalcogenide superconductor FeTe0.55Se0.45 and the conventional transition-metal dichalcogenide superconductor 2H-NbSe2. The diode response shows a striking twist-angle dependence: the efficiency peaks at crystallographic alignment and collapses with a small misorientation of ~7 deg. Importantly, the twist-angle evolution of superconducting interference measurements reveals that efficient nonreciprocity arises from asymmetric edge supercurrents, whereas bulk transport suppresses the effect. These findings establish edge states as the driving mechanism of the unconventional SDE, linking it to exotic pairing and topology in multiband iron-based superconductors. Our findings reveal intricate physics involving novel pairing symmetry, magnetism, and topology in the multiband iron-based superconductor, and offer a new route to high-performance superconducting diodes.
Superconductivity (cond-mat.supr-con)
16 pages, 4 figures
Beyond mean-field effects in Josephson oscillations and self-trapping of Bose-Einstein condensates in two-dimensional dual-core traps
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-02 20:00 EDT
Sherzod R. Otajonov, Fatkhulla Kh. Abdullaev, Akbar Shermaxmatov
We study a binary Bose gas in a symmetric dual-core, pancake-shaped trap, modelled by two linearly coupled two-dimensional Gross-Pitaevskii equations with Lee-Huang-Yang corrections. Two different cases are considered. First, we consider a spatially uniform condensate, where we identify the domains of parameters for macroscopic quantum tunnelling, self-trapping and localisation revivals. The analytical formulas for the Josephson frequencies in the zero- and $ \pi$ -phase modes are derived. As the total atom number varies, the system displays a rich bifurcation structure. In the zero-phase, two successive pitchfork bifurcations generate bistability and hysteresis, while the $ \pi$ -phase exhibits a single pitchfork bifurcation.
The second case is when the quantum droplets are in a dual-core trap. Analytical predictions for the oscillation frequencies are derived via a variational approach for the coupled dynamics of quantum droplets, and direct numerical simulations validate the results. We identify critical values of the linear coupling that separate Josephson and self-trapped regimes as the particle number changes. We also found the Andreev-Bashkin superfluid drag effect in numerical simulations of the droplet-droplet interactions in the two-core geometry.
Quantum Gases (cond-mat.quant-gas), Pattern Formation and Solitons (nlin.PS)
11 pages, 15 figures
Terahertz field-induced giant symmetry modulations in a van der Waals antiferromagnet
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Sheikh Rubaiat Ul Haque, Martin J. Cross, Sangeeta Rajpurohit, Jonah B. Haber, Christopher J. Ciccarino, Alexandra C. Zimmerman, Isabelle J. Sealey, Vadym Kulichenko, Monique Tie, Huaiyu Wang, Sharon S. Philip, Choongwon Seo, Jake D. Koralek, Luis Balicas, Mykhaylo Ozerov, Dmitry Smirnov, Liang Z. Tan, Felipe H. da Jornada, Tadashi Ogitsu, Matthias C. Hoffmann, Tony F. Heinz, Aaron M. Lindenberg
Strong-field terahertz (THz) excitations enable dynamic control over electronic, lattice and symmetry degrees of freedom in quantum materials. Here, we uncover pronounced terahertz-induced symmetry modulations and coherent phonon dynamics in the van der Waals antiferromagnet MnPS3, in which inversion symmetry is broken by its antiferromagnetic spin configuration. Time-resolved second harmonic generation measurements reveal long-lived giant oscillations in the antiferromagnetic phase, with amplitudes comparable to the equilibrium signal, driven by phonons involving percent-level atomic displacements relative to the equilibrium bond lengths. The temporal evolution of the rotational anisotropy patterns indicate a dynamic breaking of mirror symmetry, modulated by two vibrational modes at 1.7 THz and 4.5 THz, with the former corresponding to a hidden mode not observed in equilibrium spectroscopy. We show that these effects arise in part from a field-induced charge rearrangement mechanism that lowers the local crystal symmetry, and couples to the phonon modes. A long-lived field-driven response was uncovered with a complex THz polarization dependence which, in comparison to theory, indicates evidence for an antiferromagnetic-to-ferrimagnetic transition. Our results establish an effective field-tunable pathway for driving excitations otherwise weak in equilibrium, and for manipulating magnetism in low-dimensional materials via dynamical modulation of symmetry.
Strongly Correlated Electrons (cond-mat.str-el)
Classical and Multiscale Non-equilibrium Thermodynamics
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-02 20:00 EDT
Miroslav Grmela, Michal Pavelka
Classical and multiscale non-equilibrium thermodynamics have different histories and different objectives. In this Note we explain the differences and review some topics in which the multiscale viewpoint of mesoscopic time evolution of macroscopic systems helped to advance the classical non-equilibrium thermodynamics. Eventually, we illustrate the Braun-Le Chatelier principle in dissipative thermodynamics.
Statistical Mechanics (cond-mat.stat-mech), Chemical Physics (physics.chem-ph)
Breakdown of Stoner Ferromagnetism by Intrinsic Altermagnetism
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Chen Lu, Chao Cao, Huiqiu Yuan, Piers Coleman, Lun-Hui Hu
The Stoner criterion for ferromagnetism arises from interaction-driven asymmetric filling of spin bands, requiring that the spin susceptibility: (i) peaks dominantly at $ \mathbf{Q}=\bm{0}$ ; and (ii) diverges at a critical interaction strength. Here, we demonstrate that this Stoner mechanism breaks down due to competition with altermagnetic orders, even when both conditions are met. Altermagnetism in solids is characterized by collinear antiparallel spin alignment that preserves translational symmetry, and inherently fulfills these requirements. As a proof of concept, we study a two-orbital Hubbard model with electron filling near Van Hove singularities at high-symmetry momenta. Our results reveal that orbital-resolved spin fluctuations, amplified by strong inter-orbital hopping, stabilize intrinsic altermagnetic order. A quantum phase transition from altermagnetism to ferromagnetism occurs at critical Hund’s coupling $ J_H$ . We further propose directional spin conductivity anisotropy as a detectable signature of this transition via non-local spin transport. This work establishes the pivotal role of altermagnetism in correlated systems.
Strongly Correlated Electrons (cond-mat.str-el)
5 pages, 4 figures. Supplementary material is available upon request
Energy-density-driven ultrafast electronic excitations in a cuprate superconductor
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-02 20:00 EDT
Alessandra Milloch (1 and 2), Francesco Proietto (1, 2 and 3), Naman Agarwal (4), Laura Foglia (4), Riccardo Mincigrucci (4), Genda Gu (5), Claudio Giannetti (1, 2 and 6), Federico Cilento (4), Filippo Bencivenga (4), Fulvio Parmigiani (4 and 7) ((1) Department of Mathematics and Physics, Università Cattolica del Sacro Cuore, Brescia, Italy, (2) ILAMP (Interdisciplinary Laboratories for Advanced Materials Physics), Università Cattolica del Sacro Cuore, Brescia, Italy, (3) Department of Physics and Astronomy, KU Leuven, Leuven, Belgium, (4) Elettra - Sincrotrone Trieste S.C.p.A., Trieste, Italy, (5) Condensed Matter Physics and Materials Science Division, Brookhaven National Laboratory, Upton, New York, USA, (6) CNR-INO (National Institute of Optics), Brescia, Italy, (7) Dipartimento di Fisica, Università degli Studi di Trieste, Trieste, Italy)
Controlling nonequilibrium dynamics in quantum materials requires ultrafast probes with spectral selectivity. We report femtosecond reflectivity measurements on the cuprate superconductor Bi$ _2$ Sr$ _2$ CaCu$ _2$ O$ _{8+\delta}$ using free-electron laser extreme-ultraviolet (23.5–177eV) and near-infrared (1.5eV) pump pulses. EUV pulses access deep electronic states, while NIR light excites valence-band transitions. Despite these distinct channels, both schemes produce nearly identical dynamics: above $ T_c$ , excitations relax through fast (100–300fs) and slower (1–5ps) channels; below $ T_c$ , a delayed component signals quasiparticle recombination and condensate recovery. We find that when electronic excitations are involved, the ultrafast response is governed mainly by absorbed energy rather than by the microscopic nature of the excitation. In contrast, bosonic driving in the THz or mid-infrared produces qualitatively different dynamics. By demonstrating that EUV excitation of a correlated superconductor yields macroscopic dynamics converging with those from optical pumping, this work defines a new experimental paradigm: FEL pulses at core-level energies provide a powerful means to probe and control nonequilibrium electronic states in quantum materials on their intrinsic femtosecond timescales. This establishes FEL-based EUV pumping as a new capability for ultrafast materials science, opening routes toward soft X-ray and attosecond studies of correlated dynamics.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
Melting of colloidal crystal in a two-dimensional periodic substrate: Switch from a single crossover to two-stage melting
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-02 20:00 EDT
The melting transitions of a colloidal lattice confined to a two-dimensional ($ 2D$ ) periodic substrate of square symmetry are studied using Monte Carlo simulations. When the strengths of interparticle and particle-substrate interactions are comparable, the incommensurate nature of square and triangular ordering leads to the formation of a partially pinned solid with only one of the smallest {\bf G} vectors of the substrate present. This low-temperature phase has true long-range order. By varying the lattice parameter of the substrate while keeping the filling fraction constant, it is seen that the transition from this low-temperature solid to a high-temperature modulated liquid phase can happen via either a single crossover transition or by a two-stage melting process. The transitions are found to be second-order in nature when the lattice parameter is $ d \lesssim 9 \lambda$ , as confirmed by the finite-size scaling behavior of the specific heat. For the two-stage melting scenario, the intermediate phase is found to be hexatic. The transitions observed in this work are different from the predictions of the KTHNY theory. The study reveals how constraints from substrate periodicity can fundamentally alter melting dynamics, offering insights into the design of tunable colloidal systems and advancing the understanding of phase transitions in two-dimensional particle systems.
Statistical Mechanics (cond-mat.stat-mech)
Possible evidence for Harper broadening in the yellow exciton series of Cu2O at ultrahigh magnetic fields
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Zhuo Yang, Jinbo Wang, Yuto Ishii, Duncan K. Maude, Atsuhiko Miyata, Yasuhiro H. Matsuda
Hydrogen-like systems in ultra-high magnetic fields are of significant interest in interdisciplinary research. Previous studies have focused on the exciton wavefunction shrinkage under magnetic fields down to artificial crystal lattices (e.g., quantum wells, superlattices), where the effective mass approximation remains valid. However, further compression toward the natural crystal lattice scale remains experimentally challenging. In this study, we report magneto-absorption measurements on the yellow-exciton series in Cu2O using pulsed magnetic fields of up to 500 T. The strong low energy absorption features are assigned to the spin Zeeman split 2p0 and 3p0 exciton states. The high field data provides a value for the reduced effective mass of the exciton u\ast = 0.415 \pm 0.01me. Intriguingly, the broadening of the 2p0 ground state transition exhibits a sudden increase for ultrahigh magnetic fields above 300 T, providing possible evidence for Harper broadening - an indication of the breakdown of the effective mass approximation when the magnetic length becomes comparable to the lattice constant of the crystal.
Materials Science (cond-mat.mtrl-sci), Optics (physics.optics)
11 pages, 4 figures
Analytical Model of Resonant Quantum Excitation Transport in Molecular Chains at finite Temperatures: Application of Integral Transforms
New Submission | Other Condensed Matter (cond-mat.other) | 2025-10-02 20:00 EDT
Dalibor Chevizovich, Slobodanka Galovic, Vasilije Matic, Zoran Ivic, Zeljko Przulj
This study investigates the potential impact of intramolecular excitations on the active regions of biomolecular chains, which may play a role in physiological processes within living cells. We assumed that an excitation localized in a specific chain segment can modify its physical properties (e.g., local charge distribution or electric dipole moments), thereby altering its role in biochemical processes. As a consequence, the biochemical functionality of the molecular chain may be altered, or even disrupted. Moreover, quantum resonance effects may cause an excitation induced at one structural element to delocalize and appear at a distant site, potentially affecting the functionality of regions located far from the site where the excitation was initially induced.
To investigate this phenomenon, we developed and analyzed a theoretical model in which a single excitation is induced in a particular structural element of a finite molecular chain in thermal equilibrium with its environment. The interaction between the excitation and the thermal oscillations of the chain was taken into account. Differential equations for the correlation functions were derived and solved analytically using integral transformations, providing information on the probability of finding the excitation at each site of the chain. The results show that both the probability of finding the excitation at distant sites and its residence time depend on the chain’s physical characteristics, temperature, and initial excitation location.
Other Condensed Matter (cond-mat.other), Biological Physics (physics.bio-ph)
Active particles in tunable crowded environments
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-02 20:00 EDT
Venkata Manikantha Sai Ganesh Tanuku, Isha Malhotra, Lorenzo Caprini, Hartmut Lowen, Thomas Palberg, Ivo Buttinoni
Active particles affect their environment as much as the environment affects their active motion. Here, we present an experimental system where both can be simultaneously adjusted in situ using an external AC electric field. The environment consists in a two-dimensional bath of colloidal silica particles, whereas the active particles are gold-coated Janus spheres. As the electric field orthogonal to the planar layer increases, the former become stiffer and the latter become faster. The active motion evolves from a viscous like to a viscoelastic like behavior, with the reorientation frequency increasing with the particle speed. This effect culminates in the spontaneous chiralization of particle trajectories. We demonstrate that self-sustained reorientations arise from local compressions and in- teraction asymmetries, revealing a general particle-level mechanism where changes in the mechanical properties of the environment reshape active trajectories.
Soft Condensed Matter (cond-mat.soft)
16 pages, 8 figures
Temperature Dependence of the Response Functions of Graphene: Impact on Casimir and Casimi-Polder Forces in and out of Thermal Equilibrium
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
G. L. Klimchitskaya, V. M. Mostepanenko
We review and obtain some new results on the temperature dependence of spatially nonlocal response functions of graphene and their applications to calculation of both the equilibrium and nonequilibrium Casimir and Casimir-Polder forces. After a brief summary of the properties of the polarization tensor of graphene obtained within Dirac model in the framework of quantum field theory, we derive the expressions for the longitudinal and transverse dielectric functions. The behavior of these functions at different temperatures is investigated in the regions below and above the threshold. Special attention is paid to the double pole at zero frequency which is present in the transverse response function of graphene. An application of the response functions of graphene to calculation of the equilibrium Casimir force between two graphene sheets and Casimir-Polder forces between an atom (nanoparticle) and a graphene sheet is considered with due attention to the role of a nonzero energy gap, chemical potential and a material substrate underlying the graphene sheet. The same subject is discussed for out-of-thermal-equilibrium Casimir and Casimir-Polder forces. The role of the obtained and presented results for fundamental science and nanotechnology is outlined.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
21 pages, 7 figures
Physivs, v.7, N4, 44 (2025)
Polarization Domain Mapping From 4D-STEM Using Deep Learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Fintan G. Hardy, Sinead M. Griffin, Mariana Palos, Yaqi Li, Geri Topore, Aron Walsh, Michele Shelly Conroy
Polarization in ferroelectric domains arises from atomic-scale structural variations that govern macroscopic functionalities. The interfaces between these domains known as domain walls host distinct physical responses, making their identification and control critical. Four dimensional scanning transmission electron microscopy (4DSTEM) enables simultaneous acquisition of real and reciprocal-space information at the atomic scale, offering a powerful platform for domain mapping. However, conventional analyses rely on computationally intensive processing and manual interpretation, which are time consuming and prone to misalignment and diffraction artefacts. Here, we present a convolutional neural network that, with minimal training, classifies polarization directions from diffraction data and segments domains in real space. We further introduce an adaptive sampling strategy that prioritizes images from domain wall regions, reducing the number of training images required while improving accuracy and interpretability. We demonstrate this approach for domain mapping in ferroelectric boracite, Cu3B7O13Cl.
Materials Science (cond-mat.mtrl-sci)
An InAsSb surface quantum well with in-situ deposited Nb as a platform for semiconductor-superconductor hybrid devices
New Submission | Superconductivity (cond-mat.supr-con) | 2025-10-02 20:00 EDT
Sjoerd Telkamp, Zijin Lei, Tommaso Antonelli, Christian Reichl, Ilya Besedin, Georg Jakobs, Stefan Fält, Christian Marty, Rüdiger Schott, Werner Wegscheider
We present a novel semiconductor-superconductor hybrid material based on a molecular beam epitaxially grown InAsSb surface quantum well with an in-situ deposited Nb top layer. Relative to conventional Al-InAs based systems, the InAsSb surface quantum well offers a lower effective mass and stronger spin-orbit interaction, while the Nb layer has a higher critical temperature and a larger critical magnetic field. The in-situ deposition of the Nb results in a high-quality interface that enables strong coupling to the InAsSb quantum well. Transport measurements on Josephson junctions reveal an induced superconducting gap of 1.3 meV. Furthermore, a planar asymmetric SQUID is realized, exhibiting gate-tunable superimposed oscillations originating from both the individual Josephson junction and the full SQUID loop. The large induced superconducting gap combined with strong spin-orbit interaction position this material as an attractive platform for experiments exploring gate-tunable superconductivity and topological superconducting devices.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
Three-fold Superstructured Superlattice HfN/HfAlN Thin Films for Enhanced Toughness
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
M. Lorentzon, R. Hahn, J. Palisaitis, H. Riedl, L. Hultman, J. Birch, N. Ghafoor
To simultaneously achieve high hardness and high toughness in protective coatings remains a fundamental challenge. Here, we harness the superlattice architecture to combine Koehler hardening while the coherent interfaces reduce the crack driving force and improve toughness, enabling coatings that are both hard and damage tolerant. We design and fabricate epitaxial HfN$ _{1.33}$ /Hf$ _{0.76}$ Al$ _{0.24}$ N$ _{1.15}$ superlattices, deposited on MgO(001) substrates using low-energy, high-flux ion-assisted reactive magnetron sputtering. These superlattices with bilayer periods ranging from 6 to 20 nm, exhibit a unique three-fold superstructure, confirmed by X-ray diffraction and reciprocal space mapping (RSM). Each constituent forms distinct 3D checkerboard superstructures, with a period of 7.5 Å for HfN and 12.5 A for HfAlN. RSMs further reveal low mosaicity, high crystalline quality, and in-plane compressive strains, indicating well preserved coherence across interfaces. Mechanical testing shows that the superlattices maintain the high hardness of HfAlN (~36 GPa) independent of bilayer period, while surpassing the softer HfN (~27 GPa), consistent with interface-driven Koehler strengthening. Micropillar compression shows brittle fracture on the {110}<110> system, yet with distributed cracking and faster mechanical recovery compared to monolithic films, suggesting improved toughness. Cube-corner indentation further corroborate this behavior, with pile-up and suppressed fracture events. These results demonstrate that epitaxial HfN/HfAlN superlattices uniquely combine high hardness with improved toughness, enabled by their three-fold superstructured architecture. Leveraging the intrinsic high-temperature stability of HfN-based materials, this design offers a robust pathway toward next-generation protective coatings capable of maintaining performance under extreme conditions.
Materials Science (cond-mat.mtrl-sci)
24 pages, 6 figures, 1 table
Superdiffusion and antidiffusion in an aligned active suspension
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-02 20:00 EDT
Lokrshi Prawar Dadhichi, Suvendra K. Sahoo, K. Vijay Kumar, Sriram Ramaswamy
We show theoretically that an imposed uniaxial anisotropy leads to new universality classes for the dynamics of active particles suspended in a viscous fluid. In the homogeneous state, their concentration relaxes superdiffusively, stirred by the long-ranged flows generated by its own fluctuations, as confirmed by our numerical simulations. Increasing activity leads to an anisotropic diffusive instability, driven by an active contribution to the particle current proportional to the local curvature of the suspension velocity profile.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
Charge and Valley Hydrodynamics in the Quantum Hall Regime of Gapped Graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Danyu Shu, Hiroshi Funaki, Ai Yamakage, Ryotaro Sano, Mamoru Matsuo
We develop a unified viscous hydrodynamics for charge and valley transport in gapped graphene in the quantum Hall regime. We redefine Hall viscosity as a response to static electric-field gradients instead of strain, establishing a derivative hierarchy that fundamentally links it to nonlocal Hall conductivity. The theory predicts quantized Hall viscosity for charge and valley, including a ground-state contribution. Crucially, the valley current is unaffected by the Lorentz force and is directly accessible via the local pressure, namely the electrostatic potential that tracks fluid vorticity.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
15 pages, 9 figures
Fast and Sensitive Readout of a Semiconductor Quantum Dot Using an In-Situ Microwave Resonator with Enhanced Gate Lever Arm
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
We report an experimental study of a Si/SiGe double quantum dot (DQD) directly coupled to a niobium superconducting coplanar stripline (CPS) microwave resonator. This hybrid architecture enables high-bandwidth dispersive readout suitable for real-time feedback and error-correction protocols. Fast and sensitive readout is achieved primarily by optimizing the DQD gate lever arm, guided by MaSQE quantum dot simulations, which enhances the dispersive signal without requiring high-impedance resonators. We demonstrate a signal-to-noise ratio (SNR) of unity with an integration time of 34.54 nanoseconds, corresponding to a system bandwidth of 14.48 MHz and a charge sensitivity of 0.000186 e per square root hertz. Analysis of the voltage power spectral density (PSD) of the in-phase (I) and quadrature (Q) baseband signals characterizes the system’s readout noise, with the PSD’s dependence on integration time providing insight into distinct physical regimes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
18 pages, 11 figures
Material Synthesis 2025 (MatSyn25) Dataset for 2D Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Chengbo Li, Ying Wang, Qianying Wang, Zhizhi Tan, Haiqing Jia, Yi Liu, Li Qian, Nian Ran, Jianjun Liu, Zhixiong Zhang
Two-dimensional (2D) materials have shown broad application prospects in fields such as energy, environment, and aerospace owing to their unique electrical, mechanical, thermal and other properties. With the development of artificial intelligence (AI), the discovery and design of novel 2D materials have been significantly accelerated. However, due to the lack of basic theories of material synthesis, identifying reliable synthesis processes for theoretically designed materials is a challenge. The emergence of large language model offers new approaches for the reliability prediction of material synthesis processes. However, its development is limited by the lack of publicly available datasets of material synthesis processes. To address this, we present the Material Synthesis 2025 (MatSyn25), a large-scale open dataset of 2D material synthesis processes. MatSyn25 contains 163,240 pieces of synthesis process information extracted from 85,160 high-quality research articles, each including basic material information and detailed synthesis process steps. Based on MatSyn25, we developed MatSyn AI which specializes in material synthesis, and provided an interactive web platform that enables multifaceted exploration of the dataset (this https URL). MatSyn25 is publicly available, allowing the research community to build upon our work and further advance AI-assisted materials science.
Materials Science (cond-mat.mtrl-sci)
Enhancement of the WS$2$ A${1\text{g}}$ Raman Mode in MoS$_2$/WS$_2$ Heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Annika Bergmann-Iwe, Tomasz Woźniak, Mustafa Hemaid, Oisín Garrity, Patryk Kusch, Rico Schwartz, Ziyang Gan, Antony George, Ludger Wirtz, Stephanie Reich, Andrey Turchanin, Tobias Korn
When combined into van der Waals heterostructures, transition metal dichalcogenide monolayers enable the exploration of novel physics beyond their unique individual properties. However, for interesting phenomena such as interlayer charge transfer and interlayer excitons to occur, precise control of the interface and ensuring high-quality interlayer contact is crucial. Here, we investigate bilayer heterostructures fabricated by combining chemical-vapor-deposition-grown MoS$ _2$ and exfoliated WS$ _2$ monolayers, allowing us to form several heterostructures with various twist angles within one preparation step. In case of sufficiently good interfacial contact, evaluated by photoluminescence quenching, we observe a twist-angle-dependent enhancement of the WS$ _2$ A$ _{1g}$ Raman mode. In contrast, other WS$ _2$ and MoS$ _2$ Raman modes (in particular, the MoS$ _2$ A$ _{1g}$ mode) do not show a clear enhancement under the same experimental conditions. We present a systematic study of this mode-selective effect using nonresonant Raman measurements that are complemented with ab-initio calculations of Raman spectra. We find that the selective enhancement of the WS$ _2$ A$ _{1g}$ mode exhibits a strong dependence on interlayer distance. We show that this selectivity is related to the A$ _{1g}$ eigenvectors in the heterolayer: the eigenvectors are predominantly localized on one of the two layers; yet, the intensity of the MoS$ _2$ mode is attenuated because the WS$ _2$ layer is vibrating (albeit with much lower amplitude) out of phase, while the WS$ _2$ mode is amplified because the atoms on the MoS$ _2$ layer are vibrating in phase. To separate this eigenmode effect from resonant Raman enhancement, our study is extended with near-resonant Raman measurements.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Machine Learning Difference Charge Density
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Xiwen Li, LiangLiang Hong, Yingwei Chen, Hongjun Xiang
In density functional theory (DFT), the ground state charge density is the fundamental variable which determines all other ground state properties. Many machine learning charge density models are developed by prior efforts, which have been proven useful to accelerate DFT calculations. Yet they all use the total charge density (TCD) as the training target. In this work, we advocate predicting difference charge density (DCD) instead. We term this simple technique by $ \Delta$ -SAED, which leverages the prior physical information of superposition of atomic electron densities (SAED). The robustness of $ \Delta$ -SAED is demonstrated through evaluations over diverse benchmark datasets, showing an extra accuracy gain for more than 90% structures in the test sets. Using a Si allotropy dataset, $ \Delta$ -SAED is demonstrated to advance model’s transferability to chemical accuracy for non-self-consistent calculations. By incorporating physical priors to compensate for the limited expressive power of machine learning models, $ \Delta$ -SAED offers a cost-free yet robust approach to improving charge density prediction and enhancing non-self-consistent performance.
Materials Science (cond-mat.mtrl-sci)
Advection selects pattern in multi-stable emulsions of active droplets
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-02 20:00 EDT
Stefan Köstler, Yicheng Qiang, Guido Kusters, David Zwicker
Controlling the size of droplets, for example in biological cells, is challenging because large droplets typically outcompete smaller droplets due to surface tension. This coarsening is generally accelerated by hydrodynamic effects, but active chemical reactions can suppress it. We show that the interplay of these processes leads to three different dynamical regimes: (i) Advection dominates the coalescence of small droplets, (ii) diffusion leads to Ostwald ripening for intermediate sizes, and (iii) reactions finally suppress coarsening. Interestingly, a range of final droplet sizes is stable, of which one is selected depending on initial conditions. Our analysis demonstrates that hydrodynamic effects control initial droplet sizes, but they do not affect the later dynamics, in contrast to passive emulsions.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech), Biological Physics (physics.bio-ph), Fluid Dynamics (physics.flu-dyn)
4 pages, 4 figures, and Appendix
Orbital-Engineered Spin Asymmetry and Multifunctionality in Eu-Activated CaAlSiN$_3$: A First-Principles Roadmap to Optical-Thermoelectric Fusion
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Muhammad Tayyab, Faiq Umar, Sikander Azam, Qaiser Rafiq, Rajwali Khan, Muhammad Tahir Khan, Vineet Tirth, Ali Algahtani
Rare-earth-doped nitride phosphors are promising materials for solid-state lighting and photonic applications due to their thermal stability, sharp emission lines, and strong UV-blue absorption. In this work, we present a first-principles density functional theory (DFT) study, using the GGA+U approach, of pristine and Eu3+-doped CaAlSiN3 at doping levels of 8.5% and 17%. Electronic structure calculations show that Eu incorporation introduces localized 4f states within the band gap, leading to band-gap narrowing and enabling red photoluminescence through the 5D0 -> 7F2 transition. Spin-polarized density of states and spin density mapping confirm the magnetic nature of Eu3+, while charge density, Bader analysis, and electron localization function (ELF) indicate mixed ionic-covalent bonding and charge transfer from Eu to neighboring N and Al atoms, stabilizing the doped lattice. Optical spectra, including dielectric function, absorption, refractive index, and reflectivity, reveal red-shifted absorption edges and enhanced visible-range light-matter interactions, consistent with experimental red to near-infrared emission. Formation energy analysis confirms the thermodynamic feasibility of Eu substitution, while elastic constants and Pugh’s ratio indicate mechanical robustness and ductility. Thermoelectric transport properties, obtained using WIEN2k and BoltzTraP, suggest that moderate Eu3+ doping improves the power factor and reduces lattice thermal conductivity through disorder scattering. These results establish Eu-doped CaAlSiN3 as a stable and efficient red-emitting phosphor for white light-emitting diodes (WLEDs) and provide theoretical insights for crystal site engineering in advanced optoelectronic materials.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Determining the Density of In-gap States in Organic Semiconductors: A Pitfall of Photoelectron Yield Spectroscopy
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Ryotaro Nakazawa, Masaya Kitaoka, Ryota Kaimori, Manato Tateno, Runa Hoshikawa, Yuya Tanaka, Hisao Ishii
Accurate determination of electronic states with low density in the bandgap (in-gap states) is crucial for understanding and optimizing the performance of organic optoelectronic devices. In the device research field, photoelectron yield spectroscopy (PYS) has been widely used to evaluate such states, and its derivative is commonly employed to estimate the density of states (DOS). However, low-energy photons in PYS can generate excitons and anions in organic semiconductors, raising questions about whether derivative PYS spectra truly represent the DOS. Here, we applied hv-dependent high-sensitivity ultraviolet photoelectron spectroscopy with low-energy photons to probe the origin of photoelectrons in organic semiconductors. We show that PYS signals arise from the single-quantum external photoelectron effect (SQEPE) of in-gap states, from SQEPE of the singly occupied molecular orbital (SOMO) in anions, and biphotonic electron emission (BEE) effect via exciton fusions. Because the BEE signal masks the DOS, derivative PYS can misestimate the DOS of in-gap states. In contrast, constant final state yield spectroscopy (CFS-YS) can reliably determine the DOS. For example, in Tris(8-hydroxyquinoline) aluminum (Alq3), we observed BEE, and CFS-YS revealed the DOS of in-gap states and SOMO over six orders of magnitude. The direct determination of the SOMO DOS allowed us to clarify the role of Alq3 in the electron injection layer in organic light-emitting diodes. Moreover, the BEE process can act as both a carrier-generation and degradation pathway in organic optoelectronic devices. These findings demonstrate that CFS-YS provides a reliable method to determine the DOS of in-gap states and to probe exciton and/or anion interactions. We establish practical guidelines for determining the DOS of in-gap states for low-energy photon measurements, such as examining photon-flux dependence.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
To be submitted to ACS Applied Materials & Interfaces
The role of stacking and strain in mean-field magnetic moments of multilayer graphene
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
András Balogh, Zoltán Tajkov, Péter Nemes-Incze, János Koltai
Rhombohedral or ABC stacked multilayer graphene hosts a correlated magnetic ground state at charge neutrality, making it one of the simplest systems to investigate strong electronic correlations. We investigate this ground state in multilayer graphene structures using the Hubbard model in a distance dependent Slater-Koster tight binding framework. We show that by using a universal Hubbard-$ U$ term, we can accurately capture the spin polarization predicted by hybrid density functional theory calculations for both hexagonal (ABA) and rhombohedral (ABC) stackings. Using this $ U$ value, we calculate the magnetic moments of 3-8 layers of ABC and ABA graphene multilayers. We demonstrate that the structure and magnitude of these magnetic moments are robust when heterostructures are built from varying numbers of ABC and ABA multilayers. By applying different types of mechanical distortions, we study the behaviour of the magnetism in graphene systems under uniaxial strain and pressure. Our results establish a computationally efficient framework to investigate correlation-driven magnetism across arbitrary stacking configurations of graphite polytypes.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 9 figures
On the mechanism of ferromagnetic resonance in ferromagnet-superconductor trilayers
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Dariia Popadiuk, Julia Kharlan, Anatolii Kravets, Vladislav Korenivski, Jaroslaw W. Klos, Vladimir Golub
Temperature dependent magnetic properties of superconductor-ferromagnet-superconductor (SC/FM/SC) trilayers are studied both experimentally and theoretically, with a focus on ferromagnetic resonance (FMR). The influence of the SC and FM layer thicknesses on the FMR field is examined. To differentiate the mechanisms involved, we additionally investigate structures containing nonmagnetic metallic (M) or insulating (I) spacers (SC/FM/M/SC or SC/FM/I/SC). All the studied multilayers show large reductions in the FMR field below the critical temperature of the SC, except the system containing an insulating spacer (SC/FM/I/SC). This SC-induced FMR-shift (resonance field/frequency) is larger for thicker SC as well as FM layers, reaching a saturation value for very large thicknesses. To explain the measured results, an analytical model is developed, in which the FM-magnetization precession modulates the magnetic flux in the system, thereby inducing an alternating supercurrent in the SC, which in turn produces a dynamic back-action magnetic field on the FM that shifts its resonance frequency. The model considers closed current loops, where the FM layer conductively links the supercurrents flowing in the opposite directions in the two outer SC layers. Our results provide a practical route for increasing the operating frequency of magnonic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 4 figures
Non-Hermitian Skin Effect and Electronic Nonlocal Transport
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Carlos Payá, Oliver Solow, Elsa Prada, Ramón Aguado, Karsten Flensberg
Open quantum systems governed by non-Hermitian effective Hamiltonians exhibit unique phenomena, such as the non-Hermitian skin effect, where eigenstates localize at system boundaries. We investigate this effect in a Rashba nanowire coupled to a ferromagnetic lead and demonstrate that it can be detected via non-local transport spectroscopy: while local conductance remains symmetric, the non-local conductance becomes non-reciprocal. We account for this behavior using both conventional transport arguments and the framework of non-Hermitian physics. Furthermore, we explain that exceptional points shift in parameter space when transitioning from periodic to open boundary conditions, a phenomenon observed in other non-Hermitian systems but so far not explained. Our results establish transport spectroscopy as a tool to probe non-Hermitian effects in open electronic systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 4 figures
Anisotropic linear magnetoresistance in Dirac semimetal NiTe2 nanoflakes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Ding Bang Zhou, Kuang Hong Gao, Tie Lin, Yang Yang, Meng Fan Zhao, Zhi Yan Jia, Xiao Xia Hu, Qian Jin Guo, Zhi Qing Li
This work investigates the magneto-transport properties of exfoliated NiTe2 nano-flakes with varying thicknesses and disorder levels, unveiling two distinct physical mechanisms governing the observed anisotropic linear magnetoresistance (MR). For the perpendicular magnetic field configuration, the well-defined linear MR in high fields is unambiguously attributed to a classical origin. This conclusion is supported by the proportionality between the MR slope and the carrier mobility, and between the crossover field and the inverse of mobility. In stark contrast, the linear MR under parallel magnetic fields exhibits a non-classical character. It shows a pronounced enhancement with decreasing flake thickness, which correlates with an increasing hole-to-electron concentration ratio. This distinctive thickness dependence suggests an origin in the nonlinear band effects near the Dirac point, likely driven by the shift of the Fermi level. Furthermore, the strengthening of MR anisotropic with enhanced inter-layer transport contradicts the prediction of the guiding-center diffusion model for three-dimensional systems. Our findings highlight the critical roles of band topology and structural dimensional in the anomalous magneto-transport of Dirac semi-metals.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Exploring Chalcogen Influence on Sc2BeX4 (X = S, Se) for Green Energy Applications Using DFT
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Ahmad Ali, Haris Haider, Sikander Azam, Muhammad Talha, Muhammad Jawad, Imran Shakir
We present a first-principles density functional theory study of the structural, electronic, optical, and thermoelectric properties of Sc2BeX4 (X = S, Se) chalcogenides for energy applications. Both compounds are dynamically and thermodynamically stable, exhibiting negative formation energies of -2.6 eV (Sc2BeS4) and -2.2 eV (Sc2BeSe4). They feature direct band gaps of 1.8 eV and 1.2 eV, respectively, within the TB-mBJ approximation, indicating strong visible-light absorption. Optical analysis reveals high static dielectric constants (9.0 for S and 16.5 for Se), absorption peaks near 13.5 eV, and reflectivity below 30 percent. Thermoelectric calculations predict p-type conduction with Seebeck coefficients reaching 2.5e-4 V/K and electrical conductivities of 2.45e18 and 1.91e18 (Ohm m s)^-1 at 300 K. Power factors approach 1.25e11 W/K^2 m s, with a maximum dimensionless figure of merit (ZT) of 0.80 at 800 K. Calculated Debye temperatures (420 K for Sc2BeS4 and 360 K for Sc2BeSe4) imply low lattice thermal conductivity. These findings establish Sc2BeX4 chalcogenides as promising materials for photovoltaic and thermoelectric applications.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Dynamics of a bricklayer model: multi-walker realizations of true self-avoiding motion
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-02 20:00 EDT
We consider a multi-walker generalization of the true self-avoiding walk, the bricklayer model. We perform stochastic simulations and solve the continuum partial differential equations that describe the collective evolution of $ N$ bricklayers/walkers. These equations were previously derived from hydrodynamic considerations. In the large-$ N$ limit, the results from simulation agree with
the solutions of the partial differential equations.
Statistical Mechanics (cond-mat.stat-mech), Mathematical Physics (math-ph)
8 pages, 6 figures
Altermagnetism of ultrathin CrSb slabs
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Brahim Marfoua, Mohammad Amirabbasi, Marcus Ekholm
Altermagnets exhibit momentum-dependent spin splitting without net magnetization, combining characteristics of both ferromagnets and antiferromagnets, making them highly interesting for spintronics applications. CrSb is a prime candidate with a high Néel temperature ($ \sim700$ K) and a large exchange-driven splitting of $ \sim0.6$ –1eV. Using ab-initio calculations, we consider slabs of various orientations in the ultrathin limit. We find that (100) oriented slabs have spin-degenerate bands. In (0001) oriented slabs, the exchange-driven altermagnetic spin splitting collapses, but including spin-orbit coupling restores a residual anisotropic splitting of $ \sim70$ ~meV. In contrast, the (110) oriented slabs show an altermagnetic spin splitting of $ \sim400$ ~meV, and emerges as a robust candidate for realizing large, exchange-driven altermagnetism
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Deterministic Detection of Single Ion Implantation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Mason Adshead, Lok Kan Wan, Maddison Coke, Richard J Curry
Single ion implantation using focused ion beam systems enables high spatial resolution and maskless doping for rapid and scalable engineering of materials for quantum technologies, particularly qubits and colour centres in solid-state hosts. In such applications, the confidence with which a single ion can be deterministically implanted is crucial, and so the efficiency of the detection mechanism is a vital parameter. Here, we present a study of the single-ion detection efficiency for a variety of ion species (Si, P, Mn, Co, Ge, Sb, Au and Bi) into various hosts (Si, SiO2, Al2O3, GaAs, diamond and SiC). The effect of varying ion mass, charge and kinetic energy are studied, in addition to the cluster implantation of Sb, Au and Bi. We demonstrate that it is possible to achieve detection efficiencies >90% for a wide range of ion species and substrate combination through selection of the implantation parameters. Furthermore, detection efficiencies of 100% are found for the doping of Sb clusters which is of direct relevance for the future fabrication of quantum devices.
Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
15 pages, 8 figures
Unified theory of attractive and repulsive polarons in one-dimensional Bose gas
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-02 20:00 EDT
Nikolay Yegovtsev, T. Alper Yoğurt, Matthew T. Eiles, Victor Gurarie
We present a unified description of attractive and repulsive polarons, formed in a one-dimensional Bose gas hosting an impurity particle, by obtaining all ground and excited state solutions to the Gross-Pitaevskii equation. Modeling the impurity with an attractive square-well potential, we characterize the excited-state energy branches as a function of interaction strength. As the impurity-bath coupling increases, the excited states change from distinct soliton configurations to hybridized soliton-polaron states, eventually crossing over from repulsive to attractive polarons at unitarity. We identify a universal regime near this crossover where the polaron properties are accurately characterized by the zero-energy scattering length.
Quantum Gases (cond-mat.quant-gas)
Interacting spin and charge density waves in kagome metal FeGe
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
Mason L. Klemm, Tingjun Zhang, Barry L. Winn, Fankang Li, Feng Ye, Sijie Xu, Xiaokun Teng, Bin Gao, Ming Yi, Pengcheng Dai
Unveiling the interplay between spin density wave (SDW) and charge density wave (CDW) orders in correlated electron materials is important to obtain a comprehensive understanding of their electronic, structural, and magnetic properties. Kagome lattice materials are interesting because their flat electronic bands, Dirac points, and van Hove singularities can enable a variety of exotic electronic and magnetic phenomena. The kagome metal FeGe, which exhibits a CDW order deep within an A-type antiferromagnetic (AFM) phase, was found to respond dramatically to post-growth annealing - with the ability to tune the CDW repeatedly from long-range order to no (or extremely weak) order. Additionally, neutron scattering studies suggest that incommensurate magnetic peaks that onsets at $ T_{Canting}$ = $ T_{SDW} \approx$ 60 K in the system arise from a SDW order instead of the AFM double cone structure. Here we use inelastic neutron scattering to show two distinct spin excitations exist below $ T_{Canting}$ corresponding to two coexisting magnetic orders in the system in both sets of annealed samples with and without CDW. While CDW order or no order can dramatically affect the onset temperature of $ T_{Canting}$ and elastic incommensurate magnetic scattering, its impact on low-energy spin fluctuations is more limited. In both samples, a pair of gapless incommensurate spin excitations arising from the SDW order wavevector coexist with gapped commensurate spin waves from the A-type AFM order across $ T_{Canting}$ . Low-energy spin excitations for both samples couple dynamically to the lattice through enhanced magnetic scattering intensity on cooling below $ T_{CDW}$ , regardless the status of the static long-range CDW order. The incommensurate SDW order in the long-range CDW ordered sample also induces a tiny in-plane lattice distortion of the kagome lattice that is absent in the no CDW ordered sample.
Strongly Correlated Electrons (cond-mat.str-el)
High-Pressure DFT Study of BeX (X = S, Se, Te): Phonon Spectra, Optical Properties, and Thermodynamic Stability for Advanced Optoelectronic Applications
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Muhammad Shahzad, Sikander Azam, Syed Awais Ahmad, Ming Li
We present a comprehensive first-principles investigation of the structural, electronic, optical, and thermodynamic properties of BeX compounds (X = S, Se, Te) under hydrostatic pressures ranging from 0 to 10 GPa. Calculations were performed using density functional theory (DFT) within the Generalized Gradient Approximation (GGA) using the Perdew-Burke-Ernzerhof (PBE) functional, as implemented in the CASTEP code. Phonon dispersion analyses confirm the dynamical stability of all compounds across the studied pressure range, as indicated by the absence of imaginary frequencies throughout the Brillouin zone. The electronic band structure reveals pressure-induced band modifications, with BeS retaining the widest bandgap. Optical properties, including the dielectric function, absorption coefficient, reflectivity, and energy loss spectra, were computed for photon energies up to 30 eV. The materials exhibit strong optical absorption in the ultraviolet region, suggesting potential for UV optoelectronic applications. Thermodynamic parameters such as Debye temperature, heat capacity, and entropy were evaluated, showing pressure-dependent trends. Notably, increasing pressure leads to reduced atomic vibrations and heat capacity, while the Gibbs free energy exhibits a consistent slope with temperature, reflecting entropy variation. These results highlight the suitability of BeX compounds for pressure-sensitive optoelectronic and thermoelectric devices, as well as thermal barrier applications.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Temperature anomaly of the V$_Si$ and V$_C$ vacancy spin coherence time in 4H-SiC
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
P. Chrostoski, Ifeanyi I. Onwosi, D. H. Santamore
Increasing the spin coherence time (T2) is a major area of interest for spin defect systems such as the silicon (V$ _Si$ ) and carbon (V$ ^\pm _C$ ) vacancies in 4H-SiC. Usually as temperature increases, T2 decreases due to the thermal bath. Observations of electron-paramagnetic resonance and direct systematic measurements of T2 has seen an anomaly where T2 increases with increasing temperature. In this work, we investigate the mechanisms that cause the T2 temperature anomaly. We find that due to a spontaneous symmetry lowering from a motional Jahn-Teller distortion, a polaron quasi-particle is generated from the vibronic coupling. Initially, for temperatures from 8 to 20 - 40K, the coherence temperature dependence is dominated by phonon-assisted spin relaxation. At temperatures around 20 - 40K, depending on the vacancy, a thermally activated polaron hopping turns on and motional narrowing dominates and increases T2 with increasing temperature. As temperatures reach 120 - 160K, the energy barrier gets high enough to slow the polaron hopping. At this point the Larmor precession dominates, leading to decoherence. Our calculated temperature-dependent coherence agrees with what has been seen experimentally, giving a full theoretical framework for the mechanisms that cause the T2 temperature anomaly of increasing T2 with increasing temperature. The theoretical framework presented here also gives insight into these mechanisms being a probable universal phenomenon that could occur in many other defect center spin systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Spontaneous lattice distortion and crystal field effects in HoB4
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-10-02 20:00 EDT
S. Goswami, D. I. Gorbunov, D. Kriegner, I. Ishii, C. A. Correa, T. Suzuki, D. Brunt, G. Balakrishnan, S. Zherlitsyn, J. Wosnitza, O. A. Petrenko, M. S. Henriques
The tetraboride HoB4 crystallizes in a tetragonal structure (space group P4/mbm), with the Ho atoms realizing a Shastry-Sutherland lattice. It orders antiferromagnetically at TN1 = 7.1 K and undergoes further magnetic transition at TN2 = 5.7 K. The complex magnetic structures are attributed to competing order parameters of magnetic and quadrupolar origin with significant magnetoelastic coupling. Here, we investigate the response of the lattice of HoB4 across the antiferromagnetic phase transitions by using low-temperature powder x-ray diffraction and ultrasound-velocity measurements, supported by crystal electric field (CEF) calculations. Below TN2, the crystal structure of HoB4 changes to monoclinic (space group P21/b) as a macroscopic manifestation of the quadrupolar ordering. Between 300 and 3.5 K, the total distortion amplitude is 0.46~Å and the relative volume change is $ 3.5 \times 10^{-3}$ . This structural phase transition is compatible with the huge softening of the modulus $ C_{44}$ observed around TN2 due to ferroquadrupolar order. A lattice instability developing immediately below TN1 is seen consistently in x-ray and ultrasound data. CEF analysis suggests a quasi-degenerated ground state for the Ho$ ^{3+}$ ions in this system.
Strongly Correlated Electrons (cond-mat.str-el)
Optimal area exploration by resetting active particles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-10-02 20:00 EDT
Kristian Stølevik Olsen, Hartmut Löwen, Lorenzo Caprini
Identifying optimal strategies for efficient spatial exploration is crucial, both for animals seeking food and for robotic search processes, where maximizing the covered area is a fundamental requirement. Here, we propose position resetting as an optimal protocol to enhance spatial exploration in active matter systems. Specifically, we show that the area covered by an active Brownian particle exhibits a non-monotonic dependence on the resetting rate, demonstrating that resetting can optimize spatial exploration. Our results are based on experiments with active granular particles undergoing Poissonian resetting and are supported by active Brownian dynamics simulations. The covered area is analytically predicted at both large and small resetting rates, resulting in a scaling relation between the optimal resetting rate and the self-propulsion speed.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech)
Wave Packet Propagation through Graphene with Square and Triangular Patterned Circular Potential Scatterers
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
G. M. Milibaeva, H. T. Yusupov, D. G. Berdiyorova, Y. Rakhimova, M. Yusupov, A. Chaves, Kh. Rakhimov
In this study, using the Dirac continuum model combined with the split-operator technique, we investigate the propagation dynamics of wave packets in graphene in the presence of circular potential barriers arranged in square and triangular geometries. Our results reveal a non-monotonic dependence of the wave packet transmission on the number of barrier rows along the propagation direction: the transmission initially decreases as rows of barriers are removed, but then increases again when additional rows are eliminated. To explain the observed nonlinear behavior, the time evolution of the transmission probability is analyzed, providing insight into the interplay between wave packet dynamics and the spatial arrangement of potential barriers. These findings offer a pathway for designing graphene-based devices with tunable transport properties through engineered potential landscapes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Depinning of KPZ Interfaces in Fractional Brownian Landscapes
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-10-02 20:00 EDT
Neda Valizadeh, Morteza Nattagh Najafi
We explore the critical dynamics of driven interfaces propagating through a two dimensional disordered medium with long range spatial correlations, modeled using fractional Brownian motion. Departing from conventional models with uncorrelated disorder, we introduce quenched noise fields characterized by a tunable Hurst exponent H, allowing systematic control over the spatial structure of the background medium. The interface evolution is governed by a quenched Kardar Parisi Zhang equation modified to account for correlated disorder, namely QKPZ. Through analytical scaling analysis, we uncover how the presence of long-range correlations reshapes the depinning transition, alters the critical force Fc, and gives rise to a family of critical exponents that depend continuously on H. Our findings reveal a rich interplay between disorder correlations and the non-linearity term in QKPZ, leading to a breakdown of conventional universality and the emergence of nontrivial scaling behaviors. The exponents are found to change by H in the anticorrelation regime, while they are nearly constant in the correlation regime, suggesting a super-universal behavior for the latter. By a comparison with the quenched Edwards Wilkinson model, we study the effect of the non linearity term in the QKPZ model. This work provides new insights into the physics of driven systems in complex environments and paves the way for understanding transport in correlated disordered media.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn)
Non-Hermitian Dynamics in Quantum Anomalous Hall Insulators
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Le Yi, Emma Steinebronn, Asmaul Smitha Rashid, Nitin Samarth, Ramy El-Ganainy, Sahin L. Ozdemir, Morteza Kayyalha
Magnetically doped topological insulators (TIs) exhibit two distinct phases: the quantum anomalous Hall (QAH) phase when the Fermi level resides within the surface gap, and a metallic phase outside the gap. The QAH phase hosts unidirectional transport channels known as chiral edge states, while the metallic phase exhibits non-reciprocal transport due to unbalanced bidirectional edge states. Utilizing the chiral edge states in Cr-doped (Bi, Sb)2Te3 sandwich structures, we realize non-Hermitian conductance matrices in a one-dimensional Corbino chain with well-defined chirality. By tuning the boundary conditions from open to periodic, we reveal the non-Hermitian skin effect, where eigenstates localize exponentially at one end of the chain. In the metallic phase, we further observe asymmetric, bidirectional coupling between the neighboring sites in the conductance matrix, a direct consequence of the system’s intrinsic non-reciprocity. These results establish magnetic TIs as a powerful platform for investigating emergent non-Hermitian phenomena in topological systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Understanding the Coulomb explosion through neutralization dynamics in the problem of Auger-destruction
New Submission | Other Condensed Matter (cond-mat.other) | 2025-10-02 20:00 EDT
Nigora Turaeva, Boris Oksengendler, Farida Iskandarova
The Coulomb explosion is a process that occurs following the formation of multiple charges during Auger cascades, leading to the destruction of solid-state and molecular structures. For unstable multi-charged ions produced at Auger cascades, the destruction cross-section is directly related to the probability of Coulomb explosion, which depends on characteristic times of ion dissociation and electron neutralization. This study demonstrates that the atomic dissociation time decreases with charge. An expression for the neutralization time was obtained within the model, in which the probability of Coulomb explosion is considered as a competition of two processes, ion dissociation and electron neutralization. By using approximation of the effective mass, it was shown that the neutralization time is a function of the effective mass and the width of the valence band of solid states.
Other Condensed Matter (cond-mat.other)
Lattice-enabled detection of spin-dependent three-body interactions
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-10-02 20:00 EDT
C. Binegar, J. O. Austin-Harris, S. E. Begg, P. Sigdel, T. Bilitewski, Y. Liu
We present the experimental detection of coherent three-body interactions, often masked by stronger two-body effects, through nonequilibrium spin dynamics induced by controllably quenching lattice-confined spinor gases. Three-body interactions are characterized through both real-time and frequency domain analyses of the observed dynamics. Our results, well-described by an extended Bose-Hubbard model, further demonstrate the importance of three-body interactions for correctly determining atom distributions in lattice systems, which has applications in quantum sensing via spin singlets. The techniques demonstrated in this work can be directly applied to other atomic species, offering a promising avenue for future studies of higher-body interactions with broad relevance to strongly-interacting quantum systems.
Quantum Gases (cond-mat.quant-gas)
Charge dynamics of individual conductance channels within a percolation network of a nano-patterned nanocrystal quantum dot solid
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-10-02 20:00 EDT
Xiangxi Yin, Bence Papp, Shane Revel, Sk Tahmid Shahriar, Tamar S. Mentzel
Colloidal nanocrystal quantum dots (QD) enable the bottom-up assembly of designer solids. Among the multitudinous applications of QD solids, there has been great success in exploiting the tunable optical properties for LED displays, lighting, bioimaging and diagnostics. Applications dependent on electrical properties such as solar cells, photodetectors, and transistors have fallen short of their full potential because of poor control over electrical properties, and some of applications with the most promise for novelty, such as a solid-state quantum simulator for quantum computation and spintronics, are stagnant. Lack of clarity on the charge transport mechanism has been a significant barrier to progress, particularly as numerous sources of disorder are present. In this work, we make advancements in a nano-patterning technique to fabricate a 70-nm wide QD solid that is also free of several sources of structural defects. Owing to the small size and structural integrity, we isolate the charge dynamics of a single conductance channel within a percolation network. We tune parameters to measure ~10 channels, and with a time-resolved measurement, we find conductance noise that exceeds 100% of the average current. From observation of the long-time dynamics of the charge transport, including random telegraph noise, colored noise and attractor states, we model the transport with stochastic quasi-one-dimensional percolation paths. With this insight into the charge transport of QD solids unimpeded by structural defects, we provide a path for the rational design of a QD solid with electrical properties that reflect the underlying tunable, periodic potential.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 figures
exa-AMD: An Exascale-Ready Framework for Accelerating the Discovery and Design of Functional Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-10-02 20:00 EDT
Weiyi Xiaa, Maxim Moraru, Ying Wai Li, Cai-Zhuang Wang
Exascale computing is transforming the field of materials science by enabling simulations of unprecedented scale and complexity. We present exa-AMD, an open-source, high-performance simulation code specifically designed for accelerated materials discovery on modern supercomputers. exa-AMD addresses the computational challenges inherent in large-scale materials discovery by employing task-based parallelization strategies and optimized data management tailored for high performance computers. The code features a modular design, supports both distributed and on-node parallelism, and is designed for flexibility and extensibility to accommodate a wide range of materials science applications. We detail the underlying algorithms and implementation, and provide comprehensive benchmark results demonstrating strong scaling across multiple high performance computing platforms. We provide two example applications, the design of Fe-Co-Zr and Na-B-C compounds, to illustrate the code’s effectiveness in accelerating the discovery and characterization of novel materials. With only a set of elements as input, exa-AMD automates the workflow on CPU or GPU-enabled clusters, outputs the structures and energies of promising candidates, and updates the phase diagram. exa-AMD is publicly available on GitHub, with detailed documentation and reproducible test cases to support community engagement and collaborative research. This work aims to advance materials science by providing a robust, efficient, and extensible tool ready for exascale this http URL for exascale platforms.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)