CMP Journal 2025-09-18
Statistics
Nature: 2
Nature Physics: 2
Science: 15
Physical Review Letters: 13
arXiv: 60
Nature
Global warming amplifies wildfire health burden and reshapes inequality
Original Paper | Atmospheric science | 2025-09-17 20:00 EDT
Junri Zhao, Bo Zheng, Philippe Ciais, Yang Chen, Thomas Gasser, Josep G. Canadell, Longyi Zhang, Qiang Zhang
Global warming intensifies wildfires and exacerbates greenhouse gas and pollutant emissions1. However, global projections remain incomplete, hindering effective policy interventions amid uncertain warming futures2. Here, we developed an interpretable machine learning framework to project global burned areas and wildfire emissions. This framework accounts for the impacts of future climate change on fire activity and quantifies associated premature deaths and radiative forcing from fire-induced particulate matter (PM2.5). Here we show that from 2010-2014 to 2095-2099, fire carbon emissions are projected to increase by 23% under the Shared Socioeconomic Pathway (SSP) 2-4.5. Increased fire-related aerosols reduce the 0.06 W m⁻² cooling effect north of 60°N. Projections show a surge in premature deaths from wildfire smoke, reaching 1.40 (95% Confidence Interval: 0.66-2.25) million annually during 2095-2099, roughly 6 times higher than current levels. Africa is projected to experience the greatest rise in fire-related deaths (11-fold), driven by emission changes and an aging population. Europe and the U.S. would experience a 1-2-fold increase under SSP2-4.5, linked to rising fire occurrences in the mid-latitude Northern Hemisphere. Overall, the health burden would become more evenly distributed across nations of differing development levels than present patterns, underscoring the need for coordinated efforts.
Atmospheric science, Environmental sciences
Wildfire smoke exposure and mortality burden in the US under climate change
Original Paper | Climate-change impacts | 2025-09-17 20:00 EDT
Minghao Qiu, Jessica Li, Carlos F. Gould, Renzhi Jing, Makoto Kelp, Marissa L. Childs, Jeff Wen, Yuanyu Xie, Meiyun Lin, Mathew V. Kiang, Sam Heft-Neal, Noah S. Diffenbaugh, Marshall Burke
Wildfire activity has increased in the US and is projected to accelerate under future climate change 1-3. However, our understanding of the impacts of climate change on wildfire activity, smoke, and health outcomes remains highly uncertain, due to the difficulty of modeling the causal chain from climate to wildfire to air pollution and health. Here we quantify the mortality burden in the US due to wildfire smoke fine particulate matter (PM2.5) under climate change. We construct an ensemble of statistical and machine learning models that link climate to wildfire smoke PM2.5, and empirically estimate smoke PM2.5-mortality relationships using data on all recorded deaths in the US. We project that smoke PM2.5 could result in 71,420 excess deaths (95% CI: 34,930 - 98,430) per year by 2050 under a high warming scenario (SSP3-7.0) - a 73% increase relative to estimated 2011-2020 average annual excess deaths from smoke. Cumulative excess deaths from smoke PM2.5 could reach 1.9 million between 2026-2055. We find evidence for mortality impacts of smoke PM2.5 that last up to three years after exposure. When monetized, climate-driven smoke deaths result in economic damages that exceed existing estimates of climate-driven damages from all other causes combined in the US 4,5. Our research suggests that the health impacts of climate-driven wildfire smoke could be among the most important and costly consequences of a warming climate in the US.
Climate-change impacts, Environmental sciences
Nature Physics
Odd-parity quasiparticle interference in the superconductive surface state of UTe2
Original Paper | Superconducting properties and materials | 2025-09-17 20:00 EDT
Shuqiu Wang, Kuanysh Zhussupbekov, Joseph P. Carroll, Bin Hu, Xiaolong Liu, Emile Pangburn, Adeline Crepieux, Catherine Pepin, Christopher Broyles, Sheng Ran, Nicholas P. Butch, Shanta Saha, Johnpierre Paglione, Cristina Bena, J. C. Séamus Davis, Qiangqiang Gu
Although no known material exhibits intrinsic topological superconductivity, where a spin-triplet electron pairing potential has odd parity, UTe2 is now the leading candidate. Generally, the parity of a superconducting order parameter can be established using Bogoliubov quasiparticle interference imaging. However, odd-parity superconductors should support a topological quasiparticle surface band at energies within the maximum superconducting energy gap. Quasiparticle interference should then be dominated by the electronic structure of the quasiparticle surface band and only reveal the characteristics of the bulk order parameter indirectly. Here we demonstrate that at the (0-11) cleave surface of UTe2, a band of Bogoliubov quasiparticles appears only in the superconducting state. Performing high-resolution quasiparticle interference measurements then allows us to explore the dispersion of states in this superconductive surface band, showing that they exist only within the range of Fermi momenta projected onto the (0-11) surface. Finally, we develop a theoretical framework to predict the quasiparticle interference signatures of this surface band at the (0-11) surface. Its predictions are consistent with the experimental results if the bulk superconducting order parameter exhibits time-reversal conserving, odd-parity, a-axis nodal, B3u symmetry.
Superconducting properties and materials, Topological matter
Acoustic phonon phase gates with number-resolving phonon detection
Original Paper | Qubits | 2025-09-17 20:00 EDT
Hong Qiao, Zhaoyou Wang, Gustav Andersson, Alexander Anferov, Christopher R. Conner, Yash J. Joshi, Shiheng Li, Jacob M. Miller, Xuntao Wu, Haoxiong Yan, Liang Jiang, Andrew N. Cleland
Approaches to quantum computing that use itinerant photons are appealing because they have relatively few physical requirements. However, at present, many elements of photonic quantum computers are nondeterministic, presenting a challenge for large-scale devices. One alternative is to use similar schemes with itinerant phonons in solid-state devices, rather than photons, combined with superconducting transmon devices. Here we present an advancement in the ability to deterministically manipulate and measure acoustic phonon quantum states. First, we demonstrate the deterministic phase control of itinerant one- and two-phonon qubit states, which we measure using an acoustic Mach-Zehnder interferometer. We implement phonon phase control using the frequency-dependent scattering of phonon states from a superconducting transmon qubit. Additionally, we propose and implement a multiphonon detection scheme that enables coherent conversion between itinerant one- and two-phonon Fock states and transmon qutrit states, for example, transforming an entangled two-phonon output state into the entangled state of two transmons. The integration of quantum acoustics with superconducting circuits in our implementation promises further advances, including deterministic phonon quantum gates with direct applications to quantum computing.
Qubits, Single photons and quantum effects
Science
More extreme Indian monsoon rainfall in El Niño summers
Research Article | Monsoons | 2025-09-18 03:00 EDT
Spencer A. Hill, Destiny Zamir Meyers, Adam H. Sobel, Michela Biasutti, Mark A. Cane, Michael K. Tippett, Fiaz Ahmed
Extreme rainfall during the Indian summer monsoon can be destructive and deadly to the world’s third-largest economy and most populous country. Although El Niño events in the equatorial Pacific are known to suppress total summer rainfall throughout India, we show using observational data spanning 1901 to 2020 that, counterintuitively, they simultaneously intensify extreme daily rainfall. This is partly driven by increases in extreme daily values of convective buoyancy, provided that both the undilute instability of near-surface air and the dilution by mixing with drier air above are considered. El Niño could plausibly drive similar changes in other tropical regions, and our framework could be further applied to changes in hourly extremes, to other internal variability modes, and to forced trends under climate change.
Climate rather than overgrazing explains most rangeland primary productivity change in Mongolia
Research Article | Rangelands | 2025-09-18 03:00 EDT
Avralt-Od Purevjav, Tumenkhusel Avirmed, Steven W. Wilcox, Christopher B. Barrett
Rangelands are Earth’s dominant land type, supporting the livelihoods of more than 2 billion people. Concerns about rangeland degradation typically focus on overgrazing. But climate change may be a greater culprit. Using spatially disaggregated, nationwide data from Mongolia, from 1984 to 2024, we exploited seasonal variation in grazing locations to quasi-experimentally estimate the causal effects of livestock herd size, weather, and climate change on rangeland primary productivity. At interannual frequency, herd size modestly but significantly negatively affects primary productivity, with notable variation across ecological zones. The effects of weather fluctuations are, however, an order of magnitude larger. At the decadal scale, over which herders can adapt to climate change, herd size effects disappear, and temperature effects dominate. In Mongolia, climate change seems to drive most long-term change in rangeland primary productivity.
1206 genomes reveal origin and movement of Aedes aegypti driving increased dengue risk
Research Article | Mosquito genetics | 2025-09-18 03:00 EDT
Jacob E. Crawford, Dario Balcazar, Seth Redmond, Noah H. Rose, Henry A. Youd, Eric R. Lucas, Rusdiyah Sudirman Made Ali, Ashwaq Alnazawi, Athanase Badolo, Chun-Hong Chen, Luciano V. Cosme, Jennifer A. Henke, Kim Y. Hung, Susanne Kluh, Wei-Liang Liu, Kevin Maringer, Ademir Martins, María Victoria Micieli, Evlyn Pless, Aboubacar Sombié, Sinnathamby N. Surendran, Isra Wahid, Peter A. Armbruster, David Weetman, Carolyn S. McBride, Andrea Gloria-Soria, Jeffrey R. Powell, Bradley J. White
The emergence and global expansion of Aedes aegypti puts more than half of all humans at risk of arbovirus infection, but the origin of this mosquito and the impact of contemporary gene flow on arbovirus control are unclear. We sequenced 1206 genomes from 73 globally distributed locations. After evolving a preference for humans in Sahelian West Africa, the invasive subspecies Ae. aegypti aegypti (Aaa) emerged in the Americas after the Atlantic slave trade era and expanded globally. Recent back-to-Africa Aaa migration introduced insecticide resistance and anthropophily into regions with recent dengue outbreaks, raising concern that Aaa movement could increase arbovirus risk in urban Africa. These data underscore developing complexity in the fight against dengue, Zika, and chikungunya and provide a platform to further study this important mosquito vector.
Functional maps of a genomic locus reveal confinement of an enhancer by its target gene
Research Article | Molecular biology | 2025-09-18 03:00 EDT
Mathias Eder, Christina J. I. Moene, Lise Dauban, Mikhail Magnitov, Jamie Drayton, Marcel de Haas, Christ Leemans, Martijn Verkuilen, Elzo de Wit, Anders S. Hansen, Bas van Steensel
Genes are often activated by enhancers located at large genomic distances, and the importance of this positioning is poorly understood. By relocating promoter-reporter constructs into thousands of alternative positions within a single locus, we dissected the positional relationship between the mouse Sox2 gene and its distal enhancer. This revealed an intricate, sharply confined activation landscape in which the native Sox2 gene occupies an optimal position for its activation. Deletion of the gene relaxes this confinement and broadly increases reporter activity. The confining effect of the Sox2 gene is partially conferred by its ~1-kilobase coding region. Our local relocation approach provides high-resolution functional maps of a genomic locus and reveals that a gene can strongly constrain the realm of influence of its enhancer.
Categorical and semantic perception of the meaning of call types in zebra finches
Research Article | Animal communication | 2025-09-18 03:00 EDT
Julie E. Elie, Aude de Witasse-Thézy, Logan Thomas, Ben Malit, Frédéric E. Theunissen
Vocal communication in social animals involves the production and perception of various calls that ethologists categorize into call types based on their acoustical structure and behavioral context. Whether these categories indicate distinct meanings for the animals remains unknown. The zebra finch, a gregarious songbird, uses ~11 call types that are known to communicate hunger, danger, or social conflict and to establish social contact and bonding. Using auditory discrimination tasks, we show that the birds both discriminate and categorize all the call types in their vocal repertoire. In addition, systematic errors were more frequent between call types used in similar behavioral contexts than could be expected from their acoustic similarity. Thus, zebra finches organize their calls into categories and create a mental representation of the meaning of these sounds.
Genomic diversity of the African malaria vector Anopheles funestus
Research Article | Mosquito genetics | 2025-09-18 03:00 EDT
Marilou Boddé, Joachim Nwezeobi, Petra Korlević, Alex Makunin, Ousman Akone-Ella, Sonia Barasa, Mahamat Gadji, Lee Hart, Emmanuel W. Kaindoa, Katie Love, Eric R. Lucas, Ibra Lujumba, Mara Máquina, Sanjay C. Nagi, Joel O. Odero, Brian Polo, Claire Sangbakembi, Samuel Dadzie, Lizette L. Koekemoer, Dominic Kwiatkowski, Erica McAlister, Eric Ochomo, Fredros Okumu, Krijn Paaijmans, David P. Tchouassi, Charles S. Wondji, Diego Ayala, Richard Durbin, Alistair Miles, Mara K. N. Lawniczak
Anopheles funestus s.s. is a major human malaria vector across Africa. To study its evolution, especially under vector control pressure, we sequenced 656 modern specimens (collected 2014 to 2018) and 45 historic specimens (collected 1927 to 1967) from 16 African countries. Despite high genetic diversity, the species shows stable but considerable continental population structure. Although one population showed little differentiation over a century and 4000 kilometers, nearby, we found two genetically distinct ecotypes. Vector control has resulted in strong signals of selection, with some resistance alleles shared across populations through gene flow and others arising independently. Fortunately, we found that a promising gene drive target in Anopheles gambiae is highly conserved in An. funestus. These insights will enable more strategic insecticide usage and gene drive deployment, supporting malaria elimination.
Genomic demography predicts community dynamics in a temperate montane forest
Research Article | Population dynamics | 2025-09-18 03:00 EDT
James P. O’Dwyer, James A. Lutz, Tyler Schappe, Dana Alegre, Andrew N. Black, Niklaus J. Grünwald, F. Andrew Jones
Species population sizes fluctuate over time, and these temporal dynamics play a key role in governing the maintenance of biodiversity. Although modeling approaches have been developed to characterize fluctuations in species abundances, the data required to parameterize these models from scratch are substantial. Here we introduce a new approach to modeling population fluctuations on decadal timescales by relating community-level dynamics to population-level patterns encoded in plant genomes. Using genomic samples taken at a single time point to generate contemporary effective population size estimates in a temperate montane forest, we accurately predict fluctuations across three censuses. Our approach facilitates the use of genomic demography to parameterize multispecies community models in ecology and shows that population genomic data can provide accurate predictions for ecological dynamics.
Crustal stresses and damage evolve throughout the seismic cycle of the Ridgecrest fault zone
Research Article | Seismology | 2025-09-18 03:00 EDT
Jared Bryan, William B. Frank, Pascal Audet
Earthquakes abruptly release tectonic stress that builds slowly over time through the coupled evolution of faults and the surrounding crust. Seismic wavespeeds track crustal deformation and stress changes, but typical monitoring methods are most sensitive to shallow depths. Using receiver functions, we tracked rupture-zone wavespeed and anisotropy changes throughout the crust during the 2019 Ridgecrest earthquake sequence. Shallow coseismic wavespeed reductions recovered within months, whereas a deeper postseismic wavespeed drop persisted without measurable recovery over several years. The deep, persistent wavespeed drop likely reflects accumulating damage driven by postseismic deformation, suggesting two possible scenarios: (i) a slow interseismic recovery where wavespeed and anisotropy track long-term stress evolution; or (ii) permanent deformation of an immature fault zone. Both scenarios affect the dynamics and energy budget of the seismic cycle.
Adaptations to water stress and pastoralism in the Turkana of northwest Kenya
Research Article | Human genetics | 2025-09-18 03:00 EDT
A. J. Lea, I. V. Caldas, K. M. Garske, E. R. Gerlinger, J. P. Arroyo, J. Echwa, M. Gurven, C. Handley, J. C. Kahumbu, J. Kamau, P. Kinyua, F. Lotukoi, A. Lopurudoi, S. Lowasa, S. N. Njeru, R. Mallarino, D. J. Martins, P. W. Messer, C. Miano, B. Muhoya, J. Peng, T. Phung, J. D. Rabinowitz, A. Roichman, R. Siford, A. C. Stone, A. M. Taravella Oill, S. Mathew, M. A. Wilson, J. F. Ayroles
The Turkana pastoralists of Kenya inhabit arid, water-limited environments and rely largely on livestock for subsistence. Working with Turkana communities, we sequenced 367 whole genomes and identified eight regions with evidence for recent positive selection. One of these regions includes a putative regulatory element for STC1–a kidney-expressed gene involved in metabolism and the response to dehydration. We show that STC1 is induced by antidiuretic hormone in human cells, is associated with urea levels in the Turkana themselves, and is under strong and recent selection in this population as well as a second East African population, the Daasanach. This work highlights how integrating anthropological and genomic approaches can lead to a new understanding of human physiology with biomedical relevance.
Stereo-reversed E2 unlocks Z-selective C-H functionalization
Research Article | Organic chemistry | 2025-09-18 03:00 EDT
Peter J. Verardi, Elizabeth A. Ryutov, Poulami Mukherjee, Remy Lalisse, Karina Targos, Tetsuya Inagaki, Megan Kelly, Ilia A. Guzei, Marcel Schreier, Osvaldo Gutierrez, Zachary K. Wickens
The stereoselective functionalization of C-H bonds represents a central challenge in modern organic synthesis. Despite decades of innovation in C-H activation chemistry, methods for Z-selective functionalization of alkenes have eluded synthetic practitioners. Terminal alkenes present the biggest challenge for Z-selectivity as they require selective cleavage of the more hindered of two otherwise virtually identical C-H bonds. Herein, we describe the transformation of alkenes into transient 1,2-bis-sulfonium intermediates found to undergo Z-selective elimination, overturning a textbook E2 stereoselectivity rule through stabilizing interactions. We identify paired electrolysis as an enabling strategy to both selectively generate the requisite bis-sulfonium intermediate and drive its rapid elimination in situ. The resultant Z-alkenyl sulfonium linchpins provide access to a wide array of Z-alkene targets from inexpensive feedstocks through robust cross-coupling reactions.
High-capacity, reversible hydrogen storage using H–conducting solid electrolytes
Research Article | Electrochemistry | 2025-09-18 03:00 EDT
Takashi Hirose, Naoki Matsui, Takashi Itoh, Yoyo Hinuma, Kazutaka Ikeda, Kazuma Gotoh, Guangzhong Jiang, Kota Suzuki, Masaaki Hirayama, Ryoji Kanno
Hydrogen absorption and desorption in solids are pivotal reactions involved in batteries and hydrogen storage devices. However, conventional thermodynamic and electrochemical hydrogen storage using high-capacity materials suffers from high hydrogen-desorption temperatures and instability of electrolytes. In this work, we explored electrochemical hydride ion (H-)-driven hydrogen storage and developed a solid electrolyte, anti-α-AgI-type Ba0.5Ca0.35Na0.15H1.85, which exhibits excellent H- conductivity and electrochemical stability. This electrolyte is compatible with several metal-hydrogen electrodes, such as titanim hydride and magnesium hydride (MgH2), allowing for high-capacity, reversible hydrogen storage at low temperatures. Specifically, Mg-H2 cells operating as hydrogen storage devices (Mg + H2
Kinetic organization of the genome revealed by ultraresolution multiscale live imaging
Research Article | Molecular biology | 2025-09-18 03:00 EDT
Joo Lee, Liang-Fu Chen, Simon Gaudin, Kavvya Gupta, Ana Novacic, Andrew Spakowitz, Alistair Nicol Boettiger
Genome function requires regulated genome motion. However, tools to directly observe this motion in vivo have been limited in coverage and resolution. Here we introduce an approach to tile mammalian chromosomes with self-mapping fluorescent labels and track them at ultraresolution. We find that sequences separated by submegabase distances transition to proximity in tens of seconds. This rapid search is dependent on cohesin and is exhibited only within domains. Domain borders act as kinetic impediments to this search process, rather than structural boundaries. The genomic separation-dependent scaling of the search time for cis interactions violated predictions of diffusion, suggesting motor-driven folding. We also uncover cohesin-dependent processive motion at 2.7 kilobases per second. Together, these multiscale dynamics reveal the organization of the genome into kinetically associated domains.
Transposable elements are vectors of recurrent transgenerational epigenetic inheritance
Research Article | 2025-09-18 03:00 EDT
Pierre Baduel, Louna De Oliveira, Erwann Caillieux, Grégoire Bohl-Viallefond, Ciana Xu, Mounia El Messaoudi, Aurélien Petit, Maëva Draï, Matteo Barois, Vipin Singh, Alexis Sarazin, Felipe K. Teixeira, Martine Boccara, Elodie Gilbault, Antoine de France, Leandro Quadrana, Olivier Loudet, Vincent Colot
DNA methylation loss at transposable elements (TEs) can affect neighboring genes and be epigenetically inherited in plants, yet the determinants and significance of this additional system of inheritance are unknown. Here, we demonstrate in Arabidopsis thaliana that transgenerational stability of experimentally-induced hypomethylation at TE loci is constrained by small RNAs derived from related copies. Using data from >700 strains collected worldwide, we uncover similar and recurrent hypomethylation at hundreds of these TE loci, often near genes. Most natural epivariants we tested can be inherited without DNA sequence changes and are therefore bona fide epialleles, although genetic factors modulate their recurrence or persistence. Epiallelic variants often cause gene expression changes and may be targets of selection, thus revealing their contribution to heritable phenotypic variation in nature.
Scalable entanglement of nuclear spins mediated by electron exchange
Research Article | Quantum processing | 2025-09-18 03:00 EDT
Holly G. Stemp, Mark R. van Blankenstein, Serwan Asaad, Mateusz T. Mądzik, Benjamin Joecker, Hannes R. Firgau, Arne Laucht, Fay E. Hudson, Andrew S. Dzurak, Kohei M. Itoh, Alexander M. Jakob, Brett C. Johnson, David N. Jamieson, Andrea Morello
The use of nuclear spins for quantum computation is limited by the difficulty in creating genuine quantum entanglement between distant nuclei. Current demonstrations of nuclear entanglement in semiconductors rely on coupling the nuclei to a common electron, which is not a scalable strategy. In this work, we demonstrated a two-qubit controlled-Z logic operation between the nuclei of two phosphorus atoms in a silicon device, separated by up to 20 nanometers. Each atom binds separate electrons, whose exchange interaction mediates the nuclear two-qubit gate. We prepared and measured a nuclear Bell state with a fidelity of
Quantum squeezing of a levitated nanomechanical oscillator
Research Article | Quantum mechanics | 2025-09-18 03:00 EDT
Mitsuyoshi Kamba, Naoki Hara, Kiyotaka Aikawa
Manipulating the motion of macroscopic objects near their quantum mechanical uncertainties has been desired in diverse fields, including fundamental physics, sensing, and transducers. Despite progress in ground-state cooling of a levitated solid particle, realizing its nonclassical states has been elusive. Here, we demonstrate quantum squeezing of the motion of a single nanoparticle by rapidly varying its oscillation frequency. We reveal appreciable narrowing of the velocity variance to -4.9 ± 0.1 decibels of that of the ground state using free-expansion measurements. Our work shows that a levitated nanoparticle offers an ideal platform for studying nonclassical states of its motion and provides a route to developing applications in quantum sensing and exploring quantum mechanics at a macroscopic scale.
Physical Review Letters
Ultrahigh-Energy Neutrinos from Primordial Black Holes
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-18 06:00 EDT
Alexandra P. Klipfel and David I. Kaiser
Black holes born in the early Universe could account for the recently observed ultrahigh-energy astrophysical neutrinos.
Phys. Rev. Lett. 135, 121003 (2025)
Cosmology, Astrophysics, and Gravitation
Accurate Ab Initio Method for Charged Defect Scattering
Article | Condensed Matter and Materials | 2025-09-18 06:00 EDT
Rongjing Guo, Kwangrae Kim, Zhongcan Xiao, and Yuanyue Liu
Charged defect scattering of electrons plays a critical role in determining a wide range of material properties. However, there is a lack of an accurate method to calculate the scattering, as all the existing methods require assuming a specific distribution for unscreened (i.e., bare) excess charge …
Phys. Rev. Lett. 135, 126302 (2025)
Condensed Matter and Materials
Strings, Branes and Twistons: Topological Analysis of Phase Defects in Excitable Media Such as the Heart
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2025-09-18 06:00 EDT
Louise Arno, Desmond Kabus, and Hans Dierckx
Several excitable systems, such as the heart, self-organize into complex spatiotemporal patterns that involve wave collisions and rotating vortices. The dynamics between these structures are incompletely understood. Here we establish a comprehensive topological framework in three spatial dimensions.…
Phys. Rev. Lett. 135, 128402 (2025)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Cavity-Enhanced Spin-Wave Solid-State Quantum Memory
Article | Quantum Information, Science, and Technology | 2025-09-17 06:00 EDT
Leo Feldmann, Sören Wengerowsky, Antariksha Das, Stefano Duranti, Jonathan Hänni, Samuele Grandi, and Hugues de Riedmatten
We report on the realization of an efficient solid-state spin-wave quantum memory, with on-demand readout, using the full atomic frequency comb (AFC) scheme in a crystal embedded in an impedance-matched cavity. We demonstrate operation at the single-photon level by storing weak coherent …
Phys. Rev. Lett. 135, 120801 (2025)
Quantum Information, Science, and Technology
Quantum Stochastic Communication via High-Dimensional Entanglement
Article | Quantum Information, Science, and Technology | 2025-09-17 06:00 EDT
Chao Zhang, Jia-Le Miao, Xiao-Min Hu, Jef Pauwels, Yu Guo, Chuan-Feng Li, Guang-Can Guo, Armin Tavakoli, and Bi-Heng Liu
Entanglement has the ability to enhance the transmission of classical information over a quantum channel. However, fully harvesting this advantage typically requires complex entangling measurements, which are challenging to implement and scale with the system's size. In this Letter, we consider a na…
Phys. Rev. Lett. 135, 120802 (2025)
Quantum Information, Science, and Technology
Combined Annual Modulation Dark Matter Search with COSINE-100 and ANAIS-112
Article | Cosmology, Astrophysics, and Gravitation | 2025-09-17 06:00 EDT
N. Carlin et al. (COSINE-100 Collaboration, ANAIS-112 Collaboration)
Two direct-detection experiments see no evidence of a signal reported by their predecessor.
Phys. Rev. Lett. 135, 121002 (2025)
Cosmology, Astrophysics, and Gravitation
Study of ${χ}_{bJ}(2P)→ω\mathrm{ϒ}(1S)$ at Belle
Article | Particles and Fields | 2025-09-17 06:00 EDT
Z. S. Stottler et al. (The Belle Collaboration)
We report a study of the hadronic transitions , with , using mesons recorded by the Belle detector. We present the first evidence for the near-threshold transition , the analog of the near-threshold charm sector decay , with a branchi…
Phys. Rev. Lett. 135, 121902 (2025)
Particles and Fields
Efficiently Measuring $d$-Wave Pairing and Beyond in Quantum Gas Microscopes
Article | Atomic, Molecular, and Optical Physics | 2025-09-17 06:00 EDT
Daniel K. Mark, Hong-Ye Hu, Joyce Kwan, Christian Kokail, Soonwon Choi, and Susanne F. Yelin
Understanding the mechanism of high-temperature superconductivity is among the most important problems in physics, one for which quantum simulation can provide new insights. However, it remains challenging to characterize superconductivity in existing cold-atom quantum simulation platforms. Here, we…
Phys. Rev. Lett. 135, 123402 (2025)
Atomic, Molecular, and Optical Physics
Internal Stresses as Origin of the Anomalous Low-Temperature Specific Heat in Glasses
Article | Condensed Matter and Materials | 2025-09-17 06:00 EDT
Walter Schirmacher and Giancarlo Ruocco
We apply a recently developed theory of the nonphononic vibrational density of states (DOS) in glasses to investigate the impact of local frozen-in stresses on the low-temperature specific heat. Using a completely harmonic description we show that the hybridization of the local nonphononic vibration…
Phys. Rev. Lett. 135, 126102 (2025)
Condensed Matter and Materials
Phase Transitions and Remnants of Fractionalization at Finite Temperature in the Triangular Lattice Quantum Loop Model
Article | Condensed Matter and Materials | 2025-09-17 06:00 EDT
Xiaoxue Ran, Sylvain Capponi, Junchen Rong, Fabien Alet, and Zi Yang Meng
The quantum loop and dimer models are archetypal correlated systems with local constraints. With natural foundations in statistical mechanics, they are of direct relevance to various important physical concepts and systems, such as topological order, lattice gauge theories, geometric frustrations, o…
Phys. Rev. Lett. 135, 126503 (2025)
Condensed Matter and Materials
Coexistence of Topological Surface States and Superconductivity in Dirac Semimetal ${\mathrm{NiTe}}_{2}$
Article | Condensed Matter and Materials | 2025-09-17 06:00 EDT
Chen He, Jian-Zhou Zhao, Mei Du, Luo-Zhao Zhang, Jia-Ying Zhang, Kuo Yang, Noah F. Q. Yuan, Aleksandr Seliverstov, Ewald Janssens, Jun-Yi Ge, and Zhe Li
The coexistence of topological bands around the Fermi level () and superconductivity provides a fundamental platform for exploring their interplay. However, few materials inherently display both properties. In this Letter, we demonstrate the coexistence of topological surface states at the and …
Phys. Rev. Lett. 135, 126607 (2025)
Condensed Matter and Materials
Emergence of Chiral Phonons in Two-Dimensional Kagome Lattices Harboring Electronic Chirality
Article | Condensed Matter and Materials | 2025-09-17 06:00 EDT
Yanru Chen, Wei Qin, Shunhong Zhang, Ping Cui, Qian Niu, and Zhenyu Zhang
Chiral phonons have recently been established to emerge in systems containing intrinsically chiral atomic structures or magnetic systems. Here we show that such intriguing chiral phonons can also be induced in nonmagnetic Kagome lattices that lack atomic structural chirality but harbor electronic ch…
Phys. Rev. Lett. 135, 126608 (2025)
Condensed Matter and Materials
Light-Matter Correlation Energy Functional of the Cavity-Coupled Two-Dimensional Electron Gas via Quantum Monte Carlo Simulations
Article | Condensed Matter and Materials | 2025-09-17 06:00 EDT
Lukas Weber, Miguel A. Morales, Johannes Flick, Shiwei Zhang, and Angel Rubio
We perform extensive simulations of the two-dimensional cavity-coupled electron gas in a modulating potential as a minimal model for cavity quantum materials. These simulations are enabled by a newly developed quantum-electrodynamical (QED) auxiliary-field quantum Monte Carlo method. We present a pr…
Phys. Rev. Lett. 135, 126901 (2025)
Condensed Matter and Materials
arXiv
From Quantum Tsallis Entropy to Strange Metals
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
We develop a unified framework connecting quantum Tsallis statistics to electronic transport in strongly interacting systems. Starting from Rényi and Tsallis entropies, we construct a quantum Tsallis distribution that reduces to the conventional Fermi–Dirac distribution when $ q=1$ . For $ q$ slightly deviating from unity, the correction term in the occupation function can be mapped to a $ q$ -deformed Schwarzian action, corresponding to soft reparametrization modes. Coupling these soft modes to electrons via the Fermi Golden Rule yields a modified scattering rate, which reproduces conventional Fermi-liquid behavior at low temperatures and linear-in-temperature resistivity at high temperatures. Using the memory matrix formalism, we analyze magnetotransport, finding a linear-in-field magnetoresistance and a Hall angle consistent with Anderson’s two-lifetime scenario. At sufficiently low temperatures, both magnetoresistance and Hall response smoothly recover Fermi-liquid quadratic behaviors. This approach provides a controlled interpolation between Fermi-liquid and non-Fermi-liquid regimes, quantitatively linking $ q$ -deformation, soft-mode dynamics, and experimentally measurable transport coefficients in strange metals.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
18 pages
Nematic Enhancement of Superconductivity in Multilayer Graphene via Quantum Geometry
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Multilayer graphene materials have recently emerged as a fascinating versatile platform for correlated electron phenomena, hosting superconductivity, fractional quantum Hall states, and correlated insulating phases. A particularly striking experimental observation is the recurring correlation between nematicity in the normal state – manifested by spontaneous breaking of the underlying $ C_3$ symmetry – and the stabilization of robust superconducting phases. Despite its ubiquity across different materials, devices and experiments, this trend has thus far lacked a clear microscopic explanation. In this work, we identify a concrete mechanism linking nematic order to enhanced superconductivity. We demonstrate that $ C_3$ -symmetry breaking strongly reshapes the Bloch wavefunctions near the Fermi level, producing a pronounced enhancement and redistribution of the so-called quantum metric. This effect drastically amplifies superconducting pairing mediated by the quantum geometric Kohn-Luttinger mechanism [G. Shavit \it{et al.}, \href{this https URL}{Phys. Rev. Lett. 134, 176001 (2025)}]. Our analysis reveals that nematicity naturally boosts the superconducting coupling constant in experimentally relevant density regimes, providing a compelling explanation for observed correlations. These results establish the central role of geometric effects in graphene superconductivity and highlight nematicity as a promising avenue for engineering stronger unconventional superconducting states.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 4 figures
Thermal states emerging from low-entanglement background in disordered spin models
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
Yule Ma, Qianqian Chen, Mingyang Li, Zlatko Papić, Zheng Zhu
Thermalization in isolated quantum systems is governed by the eigenstate thermalization hypothesis, while strong disorder can induce its breakdown via many-body localization. Here we show that disorder can also generate a narrow band of thermal eigenstates embedded in an otherwise non-thermal spectrum. We illustrate this generic mechanism using paradigmatic spin-1 models, including Heisenberg, XY, and Affleck-Kennedy-Lieb-Tasaki (AKLT) models with several types of disorder. By analyzing their level statistics, entanglement properties and quench dynamics, we show that the disorder-induced states are genuinely thermal and we trace their origin to the null space of the disorder term in the Hamiltonian. Our results demonstrate that disorder can give rise to an unexpected coexistence of thermal and non-thermal dynamics within the same many-body spectrum.
Strongly Correlated Electrons (cond-mat.str-el), Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech)
7+10 pages; 4+13 figures
Proximity Ferroelectricity in Compositionally Graded Structures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Eugene A. Eliseev, Anna N. Morozovska, Sergei V. Kalinin, Long-Qing Chen, Venkatraman Gopalan
Proximity ferroelectricity is a novel paradigm for inducing ferroelectricity in a non-ferroelectric polar material such as AlN or ZnO that are typically unswitchable with an external field below their dielectric breakdown field. When placed in direct contact with a thin switchable ferroelectric layer (such as Al1-xScxN or Zn1-xMgxO), they become a practically switchable ferroelectric. Using the thermodynamic Landau-Ginzburg-Devonshire theory, in this work we performed the finite element modeling of the polarization switching in the compositionally graded AlN-Al1-xScxN, ZnO-Zn1-xMgxO and MgO-Zn1-xMgxO structures sandwiched in both a parallel-plate capacitor geometry as well as in a sharp probe-planar electrode geometry. We reveal that the compositionally graded structure allows the simultaneous switching of spontaneous polarization in the whole system by a coercive field significantly lower than the electric breakdown field of unswitchable polar materials. The physical mechanism is the depolarization electric field determined by the gradient of chemical composition “x”. The field lowers the steepness of the switching barrier in the otherwise unswitchable parts of the compositionally graded AlN-Al1-xScxN and ZnO-Zn1-xMgxO structures, while it induces a shallow double-well free energy potential in the MgO-like regions of compositionally graded MgO-Zn1-xMgxO structure. Proximity ferroelectric switching of the compositionally graded structures placed in the probe-electrode geometry occurs due to nanodomain formation under the tip. We predict that a gradient of chemical composition “x” significantly lowers effective coercive fields of the compositionally graded AlN-Al1-xScxN and ZnO-Zn1-xMgxO structures compared to the coercive fields of the corresponding multilayers with a uniform chemical composition in each layer.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
30 pages, including 6 figures and Supplementary Materials
Persistent Interfacial Topological Hall Effect Demonstrating Electrical Readout of Topological Spin Structures in Insulators
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Jing Li, Huilin Lai, Andrew H. Comstock, Aeron McConnell, Bharat Giri, Yu Yun, Tianhao Zhao, Xiao Wang, Yongseong Choi, Xuemei Cheng, Jian Shen, Zhigang Jiang, Dali Sun, Wenbin Wang, Xiaoshan Xu
Conventional topological Hall effects (THE) require conducting magnets, leaving insulating systems largely inaccessible. Here we introduce the interfacial topological Hall effect (ITHE), where the noncoplanar spin textures of insulating magnets are imprinted onto an adjacent heavy metal via the magnetic proximity effect (MPE) and detected electrically. In Pt/h-LuFeO3 bilayers, h-LuFeO3 hosts a topological spin structure robust against high magnetic fields, arising from a 120° triangular spin lattice with small spin canting that yields nontrivial topology but minimal magnetization. This generates a giant Hall response in Pt up to 0.5% of the longitudinal resistivity and a Hall-conductivity/magnetization ratio above 2 V^{-1}, clearly distinguishable from the spin Hall Hanle effect background. Field- and temperature-dependent analysis further reveals that Pt nanoclusters inherit topological textures from h-LuFeO3 via MPE. Unlike the conventional THE narrow peak-and-dip features, ITHE in Pt/h-LuFeO3 persists across a broad magnetic field range up to 14 T, demonstrating the exceptional stability of the underlying topological spin structure. This establishes ITHE as a powerful and sensitive probe for topological magnetism in ultrathin insulating films and paves the way for new spintronic applications.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Field-Angle Dependence of Phonon Thermal Hall Effect in Na2X2TeO6 (X = Co, Zn)
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Jian Yan, Hikaru Takeda, Haruka Iwahata, Jun-ichi Yamaura, Rajesh Kumar Ulaganathan, Kalaivanan Raju, Raman Sankar, Minoru Yamashita
The mechanism behind thermal Hall effects by phonons, which are observed in various materials, is not clarified despite the dominant contribution as heat carriers. Theoretically, mechanisms based on the intrinsic Berry phase and those on extrinsic impurity-induced scatterings have been proposed, which can be distinguished by comparing the field-angle dependence of the thermal Hall effect and that of the magnetic anisotropy. Here, we investigate the field-angle dependence of the thermal Hall effects in the antiferromagnet Na2Co2TeO6 and its non-magnetic isostructural analogue Na2Zn2TeO6 in the ac plane. We find that the field-angle dependence of the thermal Hall conductivity in both materials well follows that of the out-of-plane magnetization, showing a common mechanism by extrinsic impurity-induced scatterings in both the phonon thermal Hall effect and that enhanced by a coupling with the magnetism.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 5 figures, and Supplementary Materials. To appear in Scientific Reports
Tunable Random Telegraph Noise in Stable Perpendicular Magnetic Tunnel Junctions for Unconventional Computing
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Ahmed Sidi El Valli, Michael Tsao, Dairong Chen, Andrew D. Kent
We demonstrate that thermally stable perpendicular magnetic tunnel junctions (pMTJs), widely used in spin-transfer torque magnetic random-access memory, can be actuated with nanosecond pulses to exhibit tunable stochastic behavior. This actuated-stochastic tunnel junction (A-sMTJ) concept produces random telegraph noise, with control over fluctuation rate and probability bias. The device response is shown to be consistent with a Poisson process, with fluctuation rates tunable over more than two orders of magnitude, with average state dwell times varying from 29 ns to greater than 2.3 microseconds. These results establish A-sMTJs as a versatile platform for integrating deterministic, stochastic, and in-memory functionality on a single chip, advancing the development of probabilistic, neuromorphic, and unconventional computing systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
7 pages, 5 figures
Superparamagnetic and Stochastic-Write Magnetic Tunnel Junctions for High-Speed True Random Number Generation in Advanced Computing
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Jonathan Z. Sun, Christopher Safranski, Siyuranga Koswata, Pouya Hashemi, Andrew D. Kent
We review two magnetic tunnel junction (MTJ) approaches for compact, low-power, CMOS-integrated true random number generation (TRNG). The first employs passive-read, easy-plane superparamagnetic MTJs (sMTJs) that generate thermal-fluctuation-driven bit streams at $ 0.5$ –$ 1$ Gb/s per device. The second uses MTJs with magnetically stable free layers, operated with stochastic write pulses to achieve switching probabilities of about $ 0.5$ (\emph{i.e.}, write error rates of $ \simeq 0.5$ ), achieving $ \gtrsim 0.1$ ~Gb/s per device; we refer to these as stochastic-write MTJs (SW-MTJs). Randomness from both approaches has been validated using the NISTSP800 test suites. The sMTJ approach uses a read-only cell with low power and can be compatible with most advanced CMOS nodes, while SW-MTJs leverage standard CMOS MTJ process flows, enabling co-integration with embedded spin-transfer torque magnetic random access memory (STT-MRAM). Both approaches can achieve deep sub-0.01~$ \mu$ m$ ^2$ MTJ footprints and offer orders-of-magnitude better energy efficiency than CPU/GPU-based generators, enabling placement near logic for high-throughput random bit-streams for probabilistic computing, statistical modeling, and cryptography. In terms of performance, sMTJs generally suit applications requiring very high data-rate random bits near logic processors, such as probabilistic computing or large-scale statistical modeling. By contrast, SW-MTJs are an attractive option for edge-oriented microcontrollers, providing entropy sources for computing or cryptographic enhancement. We highlight the strengths, limitations, and integration challenges of each approach, emphasizing the need to reduce device-to-device variability in sMTJs – particularly by mitigating magnetostriction-induced in-plane anisotropy – and to improve temporal stability in SW-MTJs for robust, large-scale deployment.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
11 pages, 5 figures
Li+/H+ exchange in solid-state oxide Li-ion conductors
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Zhuohan Li, Benjamin X. Lam, Gerbrand Ceder
Understanding the moisture stability of oxide Li-ion conductors is important for their practical applications in solid-state batteries. Unlike sulfide or halide conductors, oxide conductors generally better resist degradation when in contact with water, but can still undergo topotactic ion exchange between Li ions within the structure and protons in the environment. In this work, we combine density functional theory (DFT) calculations with a machine-learning interatomic potential model to investigate the thermodynamic driving force of the Li+/H+ exchange reaction for two representative oxide Li-ion conductor families: garnets and NASICONs. Our results indicate that the high Li chemical potential in Li-stuffed garnets is responsible for the stronger driving force for exchanging Li with protons as compared to the Li-unstuffed structures. In contrast, NASICONs demonstrate a higher resistance against proton exchange, which is attributed to the lower Li chemical potential and the lower O-H bond covalency for polyanion-bonded oxygens. Our findings highlight the trade-off when using Li stuffing as a mechanism to enhance Li-ion conductivity, as it also promotes degradation by moisture. This study underscores the importance of designing Li-ion conductors that not only possess high conductivity, but also exhibit high stability in practical environments.
Materials Science (cond-mat.mtrl-sci)
From Data to Alloys Predicting and Screening High Entropy Alloys for High Hardness Using Machine Learning
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Rahul Bouri, Manikantan R. Nair, Tribeni Roy
The growing need for structural materials with strength, mechanical stability, and durability in extreme environments is driving the development of high entropy alloys. These are materials with near equiatomic mixing of five or more principal elements, and such compositional complexity often leads to improvements in mechanical properties and high thermal stability, etc. Thus, high-entropy alloys have found their applications in domains like aerospace, biomedical, energy storage, catalysis, electronics, etc. However, the vast compositional design and experimental exploration of high-entropy alloys are both time consuming and expensive and require a large number of resources. Machine learning techniques have thus become essential for accelerating high entropy alloys discovery using data driven predictions of promising alloy combinations and their properties. Hence, this work employs a machine learning framework that predicts high entropy alloy hardness from elemental descriptors such as atomic radius, valence electron count, bond strength, etc. Machine learning regression models, like LightGBM, Gradient Boosting Regressor, and Transformer encoder, were trained on experimental data. Additionally, a language model was also fine tuned to predict hardness from elemental descriptor strings. The results indicate that LightGBM has better accuracy in predicting the hardness of high entropy alloys compared to other models used in this study. Further, a combinatorial technique was used to generate over 9 million virtual high entropy alloy candidates, and the trained machine learning models were used to predict their hardness. This study shows how machine learning-driven high throughput screening and language modelling approaches can accelerate the development of next generation high entropy alloys.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
23 pages
Bilayer graphene quantum dots as a quantum simulator of Haldane topological quantum matter
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Daniel Miravet, Hassan Allami, Marek Korkusinski, Pawel Hawrylak
We demonstrate here that a chain of Bilayer Graphene Quantum Dots (BLGQD) can realize topological quantum matter by effectively simulating a spin-1 chain that hosts the Haldane phase within a specific range of parameters. We describe a chain of BLGQD with two electrons each using an atomistic tight-binding model combined with the exact diagonalization technique to solve the interacting few-electron problem. Coulomb interactions and valley mixing effects are treated within the same microscopic framework, allowing us to systematically investigate spin and valley polarization transitions as functions of interaction strength and external tuning parameters. We calculate the low energy states for single and double QDs as a function of the number of electrons, identifying regimes of highly correlated multi-electron states. We confirm the presence of a spin-one ground state for two electrons. Then, we explore two coupled QDs with 4 electrons and extend the analysis to QD arrays. Using a mapping of the BLGQD chain to an effective bilinear-biquadratic (BLBQ) spin model, we demonstrate that BLGQD arrays can work as a quantum simulator for one-dimensional spin chains with emergent many-body topological phases.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
Sandpiles with finite-range interactions
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-18 20:00 EDT
Abbas Shoja-Daliklidash, Morteza Nattagh Najafi
We investigate the sandpile model with Yukawa-type interactions, whose effective range is tuned by an external parameter $ R$ . Our results reveal that at specific values of $ R$ , the system exhibits giant avalanches that span the system, leading to percolation. The probability of such giant avalanches demonstrates two distinct regimes as a function of $ R$ : for sufficiently small $ R$ , it increases monotonically, whereas for large $ R$ it undergoes threshold dynamics, so that at certain values of $ R$ , the percolation probability exhibits abrupt jumps. We refer it to as \textit{pseudo-percolation transitions}, based on which we propose a hierarchical percolation model at the mean-field level: each percolation transition corresponds to percolation within a disc of radius $ R$ . We further examine both local and global geometrical observables. The local quantities include avalanche size, mass, and duration and sub-avalanche mass, while for the global characterization we analyze the loop length and gyration radius of the external perimeter, as well as the mass of sub-avalanches. Remarkably, all these observables exhibit power-law scaling for all values of $ R$ , with exponents that vary systematically with $ R$ . Notably, in the vicinity of the pseudo-percolation transition points, the exponents approach characteristic values, signaling a distinct critical behavior.
Statistical Mechanics (cond-mat.stat-mech)
Effective delocalization in the one-dimensional Anderson model with stealthy disorder
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2025-09-18 20:00 EDT
Carlo Vanoni, Boris L. Altshuler, Paul J. Steinhardt, Salvatore Torquato
We study analytically and numerically the Anderson model in one dimension with “stealthy” disorder, defined as having a power spectrum that vanishes in a continuous band of wave numbers. Motivated by recent studies on the optical transparency properties of stealthy hyperuniform layered media, we compute the localization length via the perturbation theory expansion of the self-energy. We find that, for fixed energy and small but finite disorder strength, there exists for any finite length system a range of stealthiness $ \chi$ for which the localization length exceeds the system size. This kind of “effective delocalization” is the result of the novel kind of correlated disorder that spans a continuous range of length scales, a defining characteristic of stealthy systems. Moreover, we support our analytical results with numerical simulations. Our results may serve as a first step in investigating the role of stealthy disorder in quantum systems, which is of both theoretical and experimental relevance.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
6 pages, 5 figures
Tuning Coupled Toroidic and Polar Orders in a Bilayer Antiferromagnet
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Chuangtang Wang, Xiaoyu Guo, Zixin Zhai, Meixin Cheng, Sang-Wook Cheong, Adam W. Tsen, Bing Lv, Liuyan Zhao
Magnetic toroidal order features a loop-like arrangement of magnetic dipole moments, thus breaking both spatial inversion (P) and time-reversal (T) symmetries while preserving their combined PT sym-metry. This PT symmetry enables a linear magnetoelectric effect, allowing the coupling between magnetic toroidicity and electric polarity. However, the detection and control of two-dimensional (2D) magnetic toroidal order and the investigation of its linear magnetoelectric response remain largely unexplored. Here, using bilayer CrSBr as a platform, which hosts an in-plane layer-antiferromagnetic (AFM) order and simultaneously exhibits a magnetic toroidal order, we show compelling evidence for tuning this 2D magnetic toroidicity and its induced electric polarity through magnetic-field-depend-ent second harmonic generation (SHG). Under an out-of-plane magnetic field, we decompose the SHG signal into a time-reversal-odd component that scales with the magnetic toroidal moment and a time-reversal-even component that is proportional to the electric polarization. When sweeping the magnetic field from positive to negative values, we observe that the magnetic toroidicity retains its sign but diminishes in magnitude at higher fields while the electric polarity flips its sign and increases in strength at increasing fields below a critical threshold. When applying an in-plane electric field along the Néel vector direction, together with an out-of-plane field, we find that the magnetic toroidal and electric polar domains are moved in a locked fashion. These findings underscore the promise of 2D magnetic toroidal order in realizing giant linear magnetoelectric effects, opening exciting possi-bilities for next-generation electronic, magnetic, optical, and photonic devices enabled by 2D mag-netoelectrics.
Materials Science (cond-mat.mtrl-sci)
12 pages, 4 figures
A model for intertwined orders in cuprates
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
R.S. Markiewicz, M. Matzelle, A. Bansil
We model the intertwined orders in the cuprate pseudogap as a textured antiferromagnet (AFM), where the texture arises from confining competing phases on topological defects, i.e., arrays of AFM domain walls. Three branches of texture are found, which can be interpreted as a strongly frustrated remnant of an underlying eutectoid phase diagram. This model can describe many key features of intertwined orders in cuprates, including the trisected superconducting dome, and provides clear evidence for a doping/hopping-parameter-dependent Mott-Slater transition in cuprates.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
24 pages + 8 figs + SM (11 pages + 5 figs). Incorporates part of arXiv:2303.11254, which is being retired
Valley-Selective Linear Dichroism and Excitonic Effects in Lieb-Lattice Altermagnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Haonan Wang, Xilong Xu, Du Li, Li Yang
Altermagnets have recently been recognized as a distinct class of magnetic materials characterized by alternative spin-split electronic structures without net magnetization. Despite intensive studies on their single-particle spintronic and valleytronic properties, many-electron interactions and optical responses of altermagnets remain less explored. In this work, we employ many-body perturbation theory to investigate excited states and their strain tunability. Using monolayer Mn2WS4 as a representative candidate, we uncover a novel spin valley-dependent excitonic selection rule in two-dimensional altermagnetic Lieb lattices. In addition to strongly bound excitons, we find that linearly polarized light selectively excites valley spin-polarized excitons. Moreover, due to the interplay between altermagnetic spin symmetry and electronic orbital character, we predict that applying uniaxial strain can lift valley degeneracy and enable the selective excitation of spin-polarized excitons, an effect not achievable in previously studied transition-metal dichalcogenides. These spin-valley-locked excitonic states and their strain tunability offer a robust mechanism for four-fold symmetric altermagnets to encode, store, and read valley/spin information.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Computational Physics (physics.comp-ph)
20 pages with 4 figures
Axial Hall Effect in Altermagnetic Lieb Lattices
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Xilong Xu, Haonan Wang, Li Yang
We predict a so-called axial Hall effect, a Berry-curvature-driven anomalous Hall response, in Lieb-lattice altermagnets. By constructing a tight-binding model, we identify the axial direction as a hidden topological degree of freedom. Breaking the double degeneracy of axial symmetry generates substantial Berry curvature and induces a pronounced anomalous Hall conductivity. First-principles calculations further confirm the emergence of this effect in strained altermagnets, particularly in ternary transition-metal dichalcogenides. We take Mn2WS4 as an example to reveal that the axial Hall effect originates from the interplay between Dresselhaus spin-orbit coupling and the intrinsic piezomagnetic response of Lieb-lattice altermagnets, leading to highly localized and enhanced Berry curvature. Remarkably, the magnitude of the axial Hall effect is significant and remains unchanged when varying the strain, highlighting the topological nature of the axial degree of freedom. Finally, in multilayer systems, the effect manifests as a distinctive thickness-dependent modulation of both anomalous and spin Hall responses. These findings emphasize the critical role of spin-orbit coupling and noncollinear spin textures in altermagnets, an area that has received limited attention, and open new pathways for exploring intrinsic Hall phenomena in topological magnetic systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
19 pages with 4 figures and 2 tables
A Computational Picture of Hydride Formation and Dissipation In Nb SRF Cavities
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Aiden Harbick, Mark Transtrum, Nathan Sitaraman, Tomás Arias, Matthias Liepe
Research linking surface hydrides to Q-disease, and the subsequent development of methods to eliminate surface hydrides, is one of the great successes of SRF cavity R&D. We use time-dependent Ginzburg-Landau to extend the theory of hydride dissipation to sub-surface hydrides. Just as surface hydrides cause Q-disease behavior, we show that sub-surface hydrides cause high-field Q-slope (HFQS) behavior. We find that the abrupt onset of HFQS is due to a transition from a vortex-free state to a vortex-penetration state. We show that controlling hydride size and depth through impurity doping can eliminate HFQS.
Superconductivity (cond-mat.supr-con), Accelerator Physics (physics.acc-ph)
11 pages, 9 figures
Magnetic phase transitions driven by quantum geometry
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
Chang-geun Oh, Taisei Kitamura, Akito Daido, Jun-Won Rhim, Youichi Yanase
We explore how the quantum geometric properties of the Bloch wave function, characterized by the Hilbert-Schmidt quantum distance, impact magnetic phases in solid-state systems. To this end, we investigate the spin susceptibility within the random phase approximation, considering the onsite Coulomb interaction. We demonstrate that spin susceptibility can be decomposed into a trivial part, dependent solely on the band dispersion, and a geometric part, where the quantum distance plays a crucial role. Focusing on a model of a quadratic band-touching semimetal, we show that a magnetic phase transition between ferromagnetic and antiferromagnetic order can be induced solely by tuning the wavefunction geometry, even while the energy spectrum is held constant. This highlights the versatility of quantum geometry as a mechanism for tuning magnetic properties independent of the energy spectrum. Applying our framework to the Fe-pnictide and kagome lattice models, we further show that the geometric contribution is decisive in stabilizing their known antiferromagnetic and ferromagnetic states, respectively. Our work sheds light on the hidden quantum geometric aspects necessary for understanding and engineering magnetic order in quantum materials.
Strongly Correlated Electrons (cond-mat.str-el)
10 pages, 4 figures
Electric-Field Control of Terahertz Response via Spin-Corner-Layer Coupling in Altermagnetic Bilayers
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Jianhua Wang, Yilin Han, Shifeng Qian, Zhenxiang Cheng, Wenhong Wang, Zhi-Ming Yu, Xiaotian Wang
Electric field control of electron charge and spin degrees of freedom is fundamental to modern semiconductor and spintronic devices. Yet controlling electromagnetic waves with an electric field, particularly in the terahertz (THz) band, remains a challenge. Here, we propose a spin-corner-layer coupling (SCLC) mechanism in second-order topological altermagnetic bilayers. By using an electric field to influence electrons between different layers, the SCLC mechanism enables simultaneous control over corner and spin degrees of freedom, thereby allowing electric-field tuning of the absorption, emission intensity, and even polarization of THz waves. Taking bilayer NiZrI$ _6$ nanodisks as a prototype, we demonstrate that an ultralow electrostatic field can switch both the spin and the layer polarizations of corner states. This dual switching modulates transition dipole moments and oscillator strengths between different corner states, thereby enabling the manipulation of THz waves. This study establishes a mechanism for the electric-field control of spin and THz waves through SCLC, yielding important implications for the advancement of THz spintronics.
Materials Science (cond-mat.mtrl-sci)
7 pages, 5 figures
Synthesis of Ultra-thin Potassium Tungsten Bronze Single Crystals with Optically Contrasting Domains and Resistive Switching
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Abdulsalam Aji Suleiman, Amir Parsi, Hafiz Muhammad Shakir, Hamid Reza Rasouli, Doruk Pehlivanoğlu, Talip Serkan Kasırga
Potassium tungsten bronzes (K$ _x$ WO$ _3$ ) are nonstoichiometric oxides in which alkali ions, i.e., K+, occupy one-dimensional tunnels of the hexagonal WO6 framework, enabling coupled ionic-lectronic transport. While their bulk and nanostructured forms have been studied extensively, controlled synthesis of single-crystalline mesoscale samples suitable for device fabrication has remained limited. Here, we report a solid-liquid-solid (SLS) growth strategy that yields high-quality K$ _x$ WO$ _3$ nanobelts with thicknesses down to ~36 nm and lateral sizes exceeding 100 um. The crystals display sharp optical domains arising from local variations in potassium occupancy, as confirmed by spatially resolved Raman spectroscopy and electron diffraction. Under applied bias, these domains vanish irreversibly, consistent with lateral redistribution of K+ ions along the tunnels. Two-terminal devices fabricated from individual nanobelts exhibit reproducible bipolar switching with resistance ratios of 10-30, characteristic short-term and long-term plasticity under pulsed excitation, and switching energies of ~25 nJ. These results establish K$ _x$ WO$ _3$ as a model tunnel-structured oxide for studying electric-field-driven alkali-ion migration, while also highlighting its potential for stable, analog resistive switching and iontronic memory applications.
Materials Science (cond-mat.mtrl-sci)
Thermal Degradation Mechanisms and Stability Enhancement Strategies in Perovskite Solar Cells: A Review
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Arghya Paul, Kanak Raj, Prince Raj Lawrence Raj, Pratim Kumar
Perovskite Solar Cells (PSCs) have garnered global research interest owing to their superior photovoltaic (PV) performance. The future of photovoltaic technology lies in PSCs since they can produce power with performance on par with the best silicon solar cells while being less expensive. PSCs have enormous potential; in just ten years, their efficiency increased from 3.8% to 25.2%, and research into new developments is still ongoing. Thermal instability is PSCs’ main disadvantage, despite their high efficiency, flexibility, and lightweight nature. This paper looks at how temperature affects the ways that hole transport layers (HTLs) like spiro-OMeTAD and perovskite layers, especially MAPbI3, degrade. Elevated temperatures cause MAPbI3 to degrade into PbI2, CH3I, and NH3, with decomposition rates affected by moisture, oxygen, and environmental factors. Mixed cation compositions, such as Cs-MA-FA, have higher thermal stability, whereas MA+ cations break-down faster under heat stress. HTLs deteriorate due to morphological changes and the hydrophilicity of dopant additions like Li-TFSI and t-BP. Alternative dopant-free HTMs, such as P3HT and inorganic materials including CuSCN, NiOx, and Cu2O, have shown improved thermal stability and efficiency. Hybrid HTLs, dopant-free designs, and interface tweaks are all viable solutions for increasing the stability of PSC. Addressing thermal stability issues remains crucial for the development of more reliable and efficient PSC technology.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
Phase stability and structural properties of the K${x}$Ca${1-x}$N novel ferromagnetic alloy from first-principles
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
K. Larbaoui, A. Lakdja, G. Bassou
We study the structural properties and phase stability of the K$ _{x}$ Ca$ _{1-x}$ N alloy using the regular-solution model based on the total energy of the mixing. The pseudopotential approach was used along with PBE functional of Perdew, Burke, and Ernzerhof (PBE). We investigated the bond-lengths distribution as a function of composition $ x$ . We also predicted the phase separation of the two partially miscible components and calculated the enthalpy $ \Delta H$ using the interaction parameter $ \Omega$ . We observe an asymmetry about $ x=0.46$ in the phase diagram due to the $ x$ -dependant interaction parameter $ \Omega=12.69-1.32x$ kcal/mole. The equilibrium solubility limit, known as the miscibility gap is found to be around 3033 K.
Materials Science (cond-mat.mtrl-sci)
7 pages, 5 figures
Pathways to Elastic Turbulence in Giant Micelles Through Curvature Ratios in Taylor-Couette Flow
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-18 20:00 EDT
Xiaoxiao Yang, Darius Marin, Charlotte Py, Olivier Cardoso, Anke Lindner, Sandra Lerouge
In the past fifteen years, flow instabilities reminiscent of the Taylor-like instabilities driven by hoop stresses, have been observed in wormlike micelles based on surfactant molecules. In particular, purely elastic instabilities and turbulence have been shown to develop on top of shear banding, a type of flow specific to the semi-dilute and concentrated regimes. These instabilities have been identified as the origin of the large body of data showing complex spatio-temporal fluctuations, collected in shear-banded systems using multiple experimental techniques. Different categories of banding have been suggested depending on their stability, which involve intrinsic properties of the system and streamline curvature. It has been shown qualitatively that instabilities are promoted by an increase of the surfactant concentration or of the curvature of the flow geometry, while an increase in temperature stabilizes the flow. Here, using benchmark shear banding micellar systems, we quantify, for the first time, the effect of the streamline curvature on these flow instabilities, focusing more specifically on the transition towards purely elastic turbulence. Using various optical visualizations, we identify two transitional pathways to elastic turbulence. We construct a generic state diagram in a parameter space based on the curvature ratio and the Weissenberg number. The nature – supercritical \textit{vs} subcritical – of the transition to elastic turbulence is discussed. The stress evolution is in favor of a change of nature from subcritical to supercritical transition as the curvature ratio increases. However we show that finite size effects cannot be neglected and may smooth artificially the stress response. Furthermore, each domain of this diagram is characterized using velocimetry measurements. Finally a scaling for the onset of elastic turbulence is determined.
Soft Condensed Matter (cond-mat.soft), Fluid Dynamics (physics.flu-dyn)
Stochastic ion emission perturbation mechanisms in atom probe tomography: Linking simulations to experiment
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Aslam Shaikh, Tero Mäkinen, François Vurpillot, Mikko Alava, Ivan Lomakin
Field evaporation in atom probe tomography (APT) includes known processes related to surface migration of atoms, such as the so-called roll-up mechanism. They lead to trajectory aberrations and artefacts on the detector. These processes are usually neglected in simulations. The inclusion of such processes is crucial for providing reliable models for the development and verification of APT reconstruction algorithms, a key part of the whole methodology. Here we include stochastic lateral velocity perturbations and a roll-up mechanism to simulations performed using the Robin–Rolland model. By comparing with experimental data from Al and Ni systems, we find the stochastic perturbation energy distributions that allow us to very accurately reproduce the detector patterns seen experimentally and thus greatly improve the accuracy of the simulations. We also explore the possible causes of remaining discrepancies between the experimental and simulated detector patterns.
Materials Science (cond-mat.mtrl-sci)
Hierarchical structures in the ground state of the spin-$\frac{1}{2}$ antiferromagnetic Heisenberg model on the pyrochlore lattice: a large scale unrestricted variational study
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
The spin-$ \frac{1}{2}$ antiferromagnetic Heisenberg model on the pyrochlore lattice(PAFH) is arguably the most well known strongly frustrated quantum magnet in three spatial dimension. As a close analogy of its two dimensional cousin, namely the spin-$ \frac{1}{2}$ antiferromagnetic Heisenberg model on the kagome lattice(KAFH), it has long been anticipated that the ground state of the spin-$ \frac{1}{2}$ PAFH may host a novel quantum spin liquid. However, due to the rapid scaling of Hilbert space with the linear size of such a three dimensional system, study of the spin-$ \frac{1}{2}$ PAFH is limited to rather small clusters and the nature of the ground state in the thermodynamic limit remains elusive. Here we apply a recently developed powerful algorithm to perform large scale unrestricted variational optimization of the ground state of the spin-$ \frac{1}{2}$ PAFH. We find that the ground state of the spin-$ \frac{1}{2}$ PAFH features a maximally resonating valence bond crystal(VBC) pattern with $ 2\times2\times2$ periodicity. There are at least four levels of hierarchical structure in such a VBC state, with the first and the second level of hierarchy related to the breaking of the inversion and the translational symmetry. We also find that an nearest-neighboring(NN)-RVB ansatz with $ 2\times 2\times 2$ periodicity can capture very well the qualitative feature of the maximally resonating VBC state. The ground state energy obtained from the NN-RVB ansatz and the generalized RVB ansatz extrapolate to $ -0.4827J/site$ and $ -0.4835J/site$ respectively in the thermodynamic limit. These results, which are obtained on clusters containing as many as $ N=8^{3}\times4=2048$ sites and wave function containing as many as $ N_{v}=16777216$ variational parameters, constitute new benchmarks for the spin-$ \frac{1}{2}$ PAFH.
Strongly Correlated Electrons (cond-mat.str-el)
15 pages,8 figures
Magnetically Assisted Trapping of Passive Colloids by Active Dipolar Chains
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-18 20:00 EDT
Arnaud Compagnie, Nicolas Vandewalle, Eric Opsomer
We investigate a trapping mechanism for passive Brownian particles based on mixtures with self-propelled dipolar colloids. Active dipoles, whose magnetic moment is oriented perpendicularly to their propulsion direction, spontaneously form dynamic chains that collapse into clusters through dipole-dipole interactions. These transient structures efficiently capture nearby passive particles, forming dense phases at relatively low global densities. Using Brownian dynamics simulations, we analyze how the capture efficiency depends on the Péclet number (Pe) and dipolar interaction strength ($ \lambda$ ). We demonstrate that an external magnetic field, applied briefly to align the active dipoles, significantly enhances trapping efficiency, with capture rates exceeding 50% under optimal conditions. Our results reveal a nontrivial competition between activity and dipolar forces, governed by the ratio $ \lambda$ /Pe, and offer insights into designing self-organized trapping strategies for passive colloids.
Soft Condensed Matter (cond-mat.soft)
Purified pseudofermion approach for the exact description of fermionic reservoirs
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
Pengfei Liang, Neill Lambert, Mauro Cirio
We present a novel method for the modeling of fermionic reservoirs using a new class of ancillary damped fermions, dubbed purified pseudofermions, which exhibit unusual free correlations. We show that this key feature, when combined with existing efficient decomposition algorithms for the reservoir correlation functions, enables the development of an easily implementable and accurate scheme for constructing effective models of fermionic reservoirs. We numerically demonstrate the validity, accuracy, efficiency and potential use of our method by studying the particle transport of spinless fermions in a one-dimensional chain. Beyond its utility as a quantum impurity solver, our method holds promise for addressing a wide range of problems involving extended systems in fields like quantum transport, quantum thermodynamics, thermal engines and nonequilibrium phase transitions.
Strongly Correlated Electrons (cond-mat.str-el)
14 pages, 6 figures, 1 table
Thermal Conductivity Limits of MoS$_2$ and MoSe$_2$: Revisiting High-Order Anharmonic Lattice Dynamics with Machine Learning Potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Tugbey Kocabas, Murat Keceli, Tanju Gurel, Milorad Milosevic, Cem Sevik
Group-VI transition metal dichalcogenides (TMDs), MoS$ _2$ and MoSe$ _2$ , have emerged as prototypical low-dimensional systems with distinctive phononic and electronic properties, making them attractive for applications in nanoelectronics, optoelectronics, and thermoelectrics. Yet, their reported lattice thermal conductivities ($ \kappa$ ) remain highly inconsistent, with experimental values and theoretical predictions differing by more than an order of magnitude. These discrepancies stem from uncertainties in measurement techniques, variations in computational protocols, and ambiguities in the treatment of higher-order anharmonic processes. In this study, we critically review these inconsistencies, first by mapping the spread of experimental and modeling results, and then by identifying the methodological origins of divergence. To this end, we bridge first-principles calculations, molecular dynamics simulations, and state-of-the-art machine learning force fields (MLFFs) including recently developed foundation models. %MACE-OMAT-0, UMA, and NEP89. We train and benchmark GAP, MACE, NEP, and \textsc{HIPHIVE} against density functional theory (DFT) and rigorously evaluate the impact of third- and fourth-order phonon scattering processes on $ \kappa$ . The computational efficiency of MLFFs enables us to extend convergence tests beyond conventional limits and to validate predictions through homogeneous nonequilibrium molecular dynamics as well. Our analysis demonstrates that, contrary to some recent claims, fully converged four-phonon processes contribute negligibly to the intrinsic thermal conductivity of both MoS$ _2$ and MoSe$ _2$ . These findings not only refine the intrinsic transport limits of 2D TMDs but also establish MLFF-based approaches as a robust and scalable framework for predictive modeling of phonon-mediated thermal transport in low-dimensional materials.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Chemical Physics (physics.chem-ph), Computational Physics (physics.comp-ph)
The influence of dimensional crossover on phase transitions and critical phenomena in condensed systems
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-18 20:00 EDT
This article is aimed at studying the effects of the dimensional crossover (DC) on physical properties of condensed systems near phase transition and critical points. Here we consider the following problems: (1) the theoretical provisions that allow to study the effect of spatial confinement on DC near phase transition and critical points; (2) the study of DC in condensed systems with the Ginzburg number $ \mathrm{Gi} <1$ , where fluctuation effects are described in different ways at the fluctuation, regular and intermediate (crossover) regions; (3) two types of DC were investigated: (a) a decrease in the linear dimensions $ L$ to the values of the correlation length of the order parameter fluctuations leads to the conversion of the dependence on thermodynamic variable into a dependence on linear sizes of 3D systems, as well as (b) a further decrease in linear sizes $ L$ the 3D-2D or 3D-1D DC happens depending on slitlike or cylindrical geometry, which is determined by the value of the lower crossover dimensionality $ d_{\rm LCD}$ ; (4) it is proposed to extend the known equalities for critical exponents by using the Mandelbrot formula for fractal dimension $ D_f$ as a critical exponent; (5) the influence of 3D-2D DC on the characteristics of the fine structure of the molecular light scattering (MLS) spectrum is studied.
Soft Condensed Matter (cond-mat.soft)
14 pages, 2 figures
Anomalous Trajectory Drift and Geometric Phases of Cyclic Spinor Solitons Induced by Virtual Magnetic Monopoles
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-09-18 20:00 EDT
Ruo-Yun Wu, Ning Mao, Xiao-Lin Li, Jie Liu, Li-Chen Zhao
We investigate the dynamics of a two-component Bose-Einstein condensate with spin-orbit coupling numerically and analytically. Under the drive of a weak segmented rotational external field, we observe that the system exhibits cyclic soliton motion; however, in contrast to the predictions of quasi-particle theory, the trajectory of the soliton center shows a distinct drift. The underlying mechanism of this anomalous drift is revealed: the moving soliton experiences a Lorentz force induced by a virtual magnetic monopole field in momentum space. We further calculate the phase evolution of the soliton during this cyclic motion and find that its geometric component comprises both an adiabatic Berry phase and a nonadiabatic Aharonov-Anandan phase. Notably, the Berry phase can be expressed in terms of the magnetic flux of the aforementioned virtual monopole field. Our findings hold implications for geometric phase theory and experiments on two-component Bose-Einstein condensates, and may establish a novel link between quantum geometry and soliton dynamics.
Quantum Gases (cond-mat.quant-gas), Pattern Formation and Solitons (nlin.PS), Quantum Physics (quant-ph)
Ruo-Yun Wu, Ning Mao, Xiao-Lin Li, Jie Liu, Li-Chen Zhao
Optimally Tensile Strained La3Ni2O7 Films as Candidate High-Temperature Superconductors on Designer Ba1-xSrxO (001) and SrO-SrTiO3 Substrates
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Liangliang Liu, Junhao Peng, Zhuangzhuang Qiao, Shuo Cai, Huafeng Dong, Yu Jia, Zhenyu Zhang
Recent experiments have observed superconductivity up to 48 K in La3Ni2O7-derived films under compressive strain imposed by the SrLaAlO4 substrate, while such films on the SrTiO3 substrate with tensile strain have failed to reach the superconducting state. Here we propose to broadly expand the choices of materials platforms to achieve high-Tc superconducting La3Ni2O7 films by proposing designer substrates of Ba1-xSrxO (x = 0 - 1) that allow to continuously tune the strain in the films from being tensile to compressive. Our systematic study of the structural and electronic reconstructions of the strained La3Ni2O7 bilayer film leads to the central finding that at the optimal tensile strain of ~2% (x ~0.25), the spectral weight of the Ni dz2 orbital is peaked right at the Fermi level, and its hybridization with the Ni dx2-y2 orbital is substantially enhanced. Consequently, the expected Tc should be unprecedentedly high, at least substantially higher than those achieved in the compressive regime. Furthermore, our detailed thickness-dependent energetic analyses show that such films can be stably grown for thicknesses equal to or beyond the bilayer regime, and predict that the SrO-terminated SrTiO3 should also be able to stabilize the films with optimal tensile strain and higher Tc’s.
Superconductivity (cond-mat.supr-con)
Contrasting magnetic anisotropy in CrCl3 and CrBr3: A first-principles study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Jiazhuang Si, Shuyuan Liu, Bing Wang, Chongze Wang, Fengzhu Ren, Yu Jia, Jun-Hyung Cho
We present a first-principles study of the contrasting easy magnetization axes(EMAs) in the layered chromium trihalides CrCl3 and CrBr3, which exhibit in-plane and out-of-plane EMAs, respectively. Using density-functional theory calculations, we show that the EMA is determined by the interplay between spin-orbit coupling-induced magnetocrystalline anisotropy energy (SOC-MAE) and shape magnetic anisotropy energy(shape-MAE) arising from dipole-dipole interactions. While the Cr d orbitals contribute similarly to the SOC-MAE in both compounds, the key difference stems from the halogen p orbitals. In CrCl3, the localized Cl 3p orbitals favor spin-flip SOC interactions, particularly between the (px, py) and (py, pz) channels. These channels contribute with opposite signs-negative and positive, respectively-leading to partial cancellation and a small net SOC-MAE. As a result, the shape-MAE exceeds the SOC-MAE in magnitude, favoring an in-plane EMA. In contrast, CrBr3 features more delocalized Br 4p orbitals, enhanced p-d hybridization, and stronger SOC. This leads to stronger spin-conserving SOC interactions, with dominant contributions from both the (px, py) and (py, pz) channels. In this case, the positive contribution from the (px, py) channel outweighs the smaller negative contribution from the (py, pz) channel, resulting in a sizable net SOC-MAE. The SOC-MAE thus surpasses the shape-MAE and stabilizes an out-of-plane EMA. These findings demonstrate that the contrasting magnetic anisotropies in CrCl3 and CrBr3 originate from differences in the spatial distribution, SOC strength, and hybridization of the halogen p orbitals, highlighting the critical role of orbital anisotropy and spin selection rules in governing magnetic behavior in layered semiconductors.
Materials Science (cond-mat.mtrl-sci)
8 pages, 6 figures
Quantum Simulations of Battery Electrolytes with VQE-qEOM and SQD: Active-Space Design, Dissociation, and Excited States of LiPF$_6$, NaPF$_6$, and FSI Salts
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Sk Mujaffar Hossain, Seung-Cheol Lee, Satadeep Bhattacharjee
Accurate prediction of excited states in battery electrolytes is central to understanding photostability, oxidative stability, and degradation. We employ hybrid quantum-classical algorithms – the Variational Quantum Eigensolver (VQE) for ground states combined with the quantum equation of motion (qEOM) for vertical singlet excitations – to study LiPF$ _6$ , NaPF$ _6$ , LiFSI, and NaFSI. Compact active spaces were constructed from frontier orbitals, mapped to qubits, and reduced via symmetry tapering and commuting-group measurements to lower sampling cost. Within $ \sim$ 10-qubit models, VQE-qEOM agrees closely with exact diagonalization of the same Hamiltonians, while sample-based quantum diagonalization (SQD) in larger active spaces recovers near-exact (subspace-FCI) energies. The spectra display clear anion and cation trends: PF$ _6$ salts exhibit higher first-excitation energies (e.g., LiPF$ _6$ $ \approx$ 13.2 eV) and a compact three-state cluster at 12-13 eV, whereas FSI salts show substantially lower onsets ($ \approx$ 8-9 eV) with a near-degenerate (S$ _1$ ,S$ _2$ ) followed by S$ _3$ $ \sim$ 1.3 eV higher. Substituting Li$ ^+$ with Na$ ^+$ narrows the gap by $ \sim$ 0.4-0.8 eV within each anion family. Converting S$ _1$ to wavelengths places the onsets in the deep-UV (LiPF$ _6$ $ \sim$ 94 nm; NaPF$ _6$ $ \sim$ 100 nm; LiFSI $ \sim$ 141 nm; NaFSI $ \sim$ 148 nm). All results pertain to isolated species or embedded clusters appropriate to the NISQ regime; solvent shifts can be incorporated a posteriori via classical $ \Delta$ -solvation or static embedding. These results demonstrate that current quantum algorithms can deliver chemically meaningful excitation and binding trends for realistic electrolyte motifs and provide quantitative baselines to guide electrolyte screening and design.
Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
Crystal Orientation Dependence of Extreme Near-Field Heat Transfer between Polar Materials Governed by Surface Phonon Modes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Wei-Zhe Yuan, Yangyu Guo, Hong-Liang Yi
Due to the rapid development of micro- and nano-manufacturing and electronic devices, heat transfer at the transition regime between radiation and conduction becomes increasingly important. Recent work has demonstrated the importance of nonlocal optical response and phonon tunneling. However, it remains unclear how the crystal orientation impacts them. In this work, we study this effect on heat transport across vacuum gaps between magnesium oxide (MgO) by nonequilibrium molecular dynamics (NEMD) simulation. At 5Ågaps, the overall thermal conductance exhibits 30% enhancement for [100] orientation versus [110] and [210], while becoming orientation-insensitive beyond 6~Å. When the gap size is extremely small, the crystal orientation significantly impacts the resonance frequencies of spectral thermal conductance which are quite close to those of unique surface phonon modes distinct from bulk counterparts. As the gap size gradually increases, the spectral thermal conductance gradually converges to the predicted results of fluctuation-electrodynamics (FE) theory in the long-wavelength approximation. Our findings reveal how surface phonon modes govern extreme near-field heat transfer across nanogap, providing insights for thermal management in electronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 6 figures
Spin-Polarized Josephson Supercurrent in Nodeless Altermagnets
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Chuang Li, Jin-Xing Hou, Fu-Chun Zhang, Song-Bo Zhang, Lun-Hui Hu
Long-range propagation of equal-spin triplet Cooper pairs typically occurs in ferromagnet/$ s$ -wave superconductor junctions, where net magnetization plays a crucial role. Here, we propose a fundamentally different scenario in which Josephson supercurrents mediated exclusively by spin-triplet pairings emerge in systems with \textit{zero} net magnetization. We identify collinear altermagnets, particularly a subclass termed nodeless altermagnets, as ideal platforms to realize this phenomenon. These materials host spin-split Fermi surfaces that do not intersect altermagnetic nodal lines and support maximal spin-valley polarization, yielding fully spin-polarized electronic states at each valley. Consequently, Josephson junctions based on nodeless altermagnets sustain supercurrents solely through spin-polarized triplet pairing correlations, simultaneously contributed by spin-up Cooper pairs from one valley and spin-down Cooper pairs from the other. Furthermore, controlling the relative local inversion-symmetry breaking at the two interfaces enables a robust 0–$ \pi$ transition without fine tuning, while adjusting the junction orientation allows a crossover between pure triplet and mixed singlet-triplet states. Our work thus establishes nodeless altermagnets as a unique platform for altermagnetic superconductors with magnetization-free spin-polarized supercurrents.
Superconductivity (cond-mat.supr-con)
Direct observation of nanoscale pinning centers in Ce(Co0.8Cu0.2)5.4 permanent magnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Nikita Polin, Shangbin Shen, Fernando Maccari, Alex Aubert, Esmaeil Adabifiroozjaei, Tatiana Smoliarova, Yangyiwei Yang, Xinren Chen, Yurii Skourski, Alaukik Saxena, András Kovács, Rafal E. Dunin-Borkowski, Michael Farle, Bai-Xiang Xu, Leopoldo Molina-Luna, Oliver Gutfleisch, Baptiste Gault, Konstantin Skokov
Permanent magnets containing rare earth elements are essential components for the electrification of society. Ce(Co1-xCux)5 permanent magnets are a model system known for their substantial coercivity, yet the underlying mechanism remains unclear. Here, we investigate Ce(Co0.8Cu0.2)5.4 magnets with a coercivity of 1 T. Using transmission electron microscopy (TEM) and atom probe tomography (APT), we identify a nanoscale cellular structure formed by spinodal decomposition. Cu-poor cylindrical cells (5-10 nm in diameter, ~20 nm long) have a disordered CeCo5-type structure and a composition Ce(Co0.9Cu0.1)5.3. Cu-rich cell boundaries are ~ 5 nm thick and exhibit a modified CeCo5 structure, with Cu ordered on the Co sites and a composition Ce(Co0.7Cu0.3)5.0. Micromagnetic simulations demonstrate that the intrinsic Cu concentration gradients up to 12 at.% Cu/nm lead to a spatial variation in magnetocrystalline anisotropy and domain wall energy, resulting in effective pinning and high coercivity. Compared to Sm2Co17-type magnets, Ce(Co0.8Cu0.2)5.4 displays a finer-scale variation of conventional pinning with lower structural and chemical contrast in its underlying nanostructure. The identification of nanoscale chemical segregation in nearly single-phase Ce(Co0.8Cu0.2)5.4 magnets provides a microstructural basis for the long-standing phenomenon of “giant intrinsic magnetic hardness” in systems such as SmCo5-xMx, highlighting avenues for designing rare-earth-lean permanent magnets via controlled nanoscale segregation.
Materials Science (cond-mat.mtrl-sci)
Impulsive shock wave propagation in granular packings under gravity
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-18 20:00 EDT
S. van den Wildenberg, X. Nguyen, A. Tourin, X. Jia
We experimentally investigate the impulsive shock propagation caused by an impact into vertically oriented 3D granular packings under gravity. We observe a crossover of wave propagation, from sound excitation at low impact to shock front formation at high impact. One of our findings is a nonlinear acoustic regime prior to the shock regime in which the wave speed decreases with the particle-velocity amplitude due to frictional sliding and rearrangement. Also, we show that the impulsive shock waves at high impact exhibit a characteristic spatial width of approximately 10 particle diameters, regardless of shock amplitude. This finding is similar to that observed in 1D granular chains and appears to be independent of the contact microstructure, whether involving dry or wet glass beads, or sand particles. The final and main finding is that we observe the coexistence of the shock front and the sound waves (ballistic propagation and multiple scattering), separated by a distinct time interval. This delay increases with impact amplitude, due to the increase shock speed on one hand and the decrease of the elastic modulus (and sound speed) in mechanically weakened granular packings by high impact on the other hand. Introducing a small amount of wetting oil into glass bead packings leads to significant viscous dissipation of scattered acoustic waves, while only slightly affecting the shock waves evidenced by a modest increase in shock front width. Our study reveals that shock-induced sound waves and scattering play an important role in shock wave attenuation within a mechanically weakened granular packing by impact. Investigating impact-driven wave propagation through such a medium also offers one way of interrogating a 3D FPUT-like system where nonlinear and linear forces between grains are involved.
Soft Condensed Matter (cond-mat.soft)
Plasticity-induced multistability on fast and slow timescales enables optimal information encoding and spontaneous sequence discrimination
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-18 20:00 EDT
Giacomo Barzon, Daniel M. Busiello, Giorgio Nicoletti
Neural circuits exhibit remarkable computational flexibility, enabling adaptive responses to noisy and ever-changing environmental cues. A fundamental question in neuroscience concerns how a wide range of behaviors can emerge from a relatively limited set of underlying biological mechanisms. In particular, the interaction between activities of neuronal populations and plasticity modulation of synaptic connections may endow neural circuits with a variety of functional responses when coordinated over different characteristic timescales. Here, we develop an information-theoretic framework to quantitatively explore this idea. We consider a stochastic model for neural activities that incorporates the presence of a coupled dynamic plasticity and time-varying stimuli. We show that long-term plasticity modulations play the functional role of steering neural activities towards a regime of optimal information encoding. By constructing the associated phase diagram, we demonstrate that either Hebbian or anti-Hebbian plasticity may become optimal strategies depending on how the external input is projected to the target neural populations. Conversely, short-term plasticity enables the discrimination of temporal ordering in sequences of inputs by navigating the emergent multistable attractor landscape. By allowing a degree of variability in external stimuli, we also highlight the existence of an optimal variability for sequence discrimination at a given plasticity strength. In summary, the timescale of plasticity modulation shapes how inputs are represented in neural activities, thereby fundamentally altering the computational properties of the system. Our approach offers a unifying information-theoretic perspective of the role of plasticity, paving the way for a quantitative understanding of the emergence of complex computations in coupled neuronal-synaptic dynamics.
Statistical Mechanics (cond-mat.stat-mech), Neurons and Cognition (q-bio.NC)
Tuning and Suppression of YIG Magnetisation Dynamics via Antiferromagnetic Interface Coupling
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Oscar Cespedes, Hari B. Vasili, Matthew Rogers, Paul S. Keatley, Manan Ali, Bryan Hickey, Robert J. Hicken
The magnetisation dynamics of yttrium iron garnet (Y3Fe5O12, YIG) are key to the operation of spintronic and microwave devices. Here, we report a pathway to manipulate the frequency, damping and absorption of YIG thin films via interface coupling. The growth on YIG of PtMn, a metallic antiferromagnet, leads to a power dependence of the oscillation frequency and an increased linewidth at low fields. In gadolinium iron garnet/YIG film bilayers, the two films couple antiferromagnetically at low temperatures and there is a strong damping of the magnetisation dynamics that is further enhanced at the spin-flop field, suppressing the FMR signal. When combining both GdIG and PtMn interfaces, we can tune the exponent of the power dependence of frequency with field and achieve an almost complete quenching of the magnetisation dynamics over a range of fields/frequencies due to non-collinear magnetic order. These effects offer a means to tune and suppress magnetisation dynamics for frequency filters, magnonics, spin pumping and other applications.
Materials Science (cond-mat.mtrl-sci)
10 pages, 4 figures
Oscillating ring ferrodark solitons with breathing nematic core in a homogeneous spinor superfluid
New Submission | Quantum Gases (cond-mat.quant-gas) | 2025-09-18 20:00 EDT
We study the dynamics of ring ferrodark solitons (FDSs) in a homogeneous quasi-two-dimensional (2D) ferromagnetic spin-1 Bose-Einstein condensate (BEC). In contrast to the usual expanding dynamics of ring dark solitons in a homogeneous system, the ring FDS radius exhibits self-sustained oscillations accompanied by the nematic tensor breathing at the magnetization-vanishing ring FDS core. When the ring radius greatly exceeds the FDS width, motion is nearly elastic, and we derive the ring-radius equation of motion (EOM) which admits exact solutions. This equation can be recast into a form analogous to the inviscid Rayleigh-Plesset equation governing spherical bubble dynamics in classical fluids, but with anomalous terms. At the ring FDS core, the nematic tensor motion is parameterized by a single parameter that connects the two types of FDSs monotonically. Beyond the hydrodynamics regime, density and spin wave emissions become significant and cause energy loss, shrinking the ring FDS radius oscillation; below a threshold, collapses occur followed by the ring FDS annihilation. In the zero quadratic Zeeman energy limit, the ring radius and eigenvalues of the nematic tensor become stationary, while oscillations of the nematic tensor components, driven by the ring curvature, persist at the core. Excellent agreements are found between analytical predictions and numerical simulations.
Quantum Gases (cond-mat.quant-gas), Pattern Formation and Solitons (nlin.PS)
4 pages, 3 figures
Fate of Topological Dirac Magnons in van der Waals Ferromagnets at Finite Temperature
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
Rintaro Eto, Ignacio Salgado-Linares, Masahito Mochizuki, Johannes Knolle, Alexander Mook
Dirac magnons, the bosonic counterparts of Dirac fermions in graphene, provide a unique platform to explore symmetry-protected band crossings and quantum geometry in magnetic insulators, while promising high-velocity, low-dissipation spin transport for next-generation magnonic technologies. However, their stability under realistic, finite-temperature conditions remains an open question. Here, we develop a comprehensive microscopic theory of thermal magnon-magnon interactions in van der Waals honeycomb ferromagnets, focusing on both gapless and gapped Dirac magnons. Using nonlinear spin-wave theory with magnon self-energy corrections and a T-matrix resummation that captures two-magnon bound states, we quantitatively reproduce temperature- and momentum-dependent energy shifts and linewidths observed experimentally in the gapless Dirac magnon material CrBr$ _3$ , even near the Curie temperature. Our approach resolves discrepancies between prior theoretical predictions and experiment and highlight the significant role of bound states in enhancing magnon damping at low temperatures. For gapped Dirac magnon materials such as CrI$ _3$ , CrSiTe$ _3$ , and CrGeTe$ _3$ , we find a thermally induced reduction of the topological magnon gap but no evidence of thermally driven topological transitions. Classical atomistic spin dynamics simulations corroborate the gap’ s robustness up to the Curie temperature. Furthermore, we establish a practical criterion for observing topological gaps by determining the minimum ratio of Dzyaloshinskii-Moriya interaction to Heisenberg exchange required to overcome thermal broadening throughout the ordered phase, typically around 5%. Our results clarify the interplay of thermal many-body effects and topology in low-dimensional magnets and provide a reliable framework for interpreting spectroscopic experiments.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
30 pages, 17 figures
Three-dimensional magnetization textures as quaternionic functions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Konstantin L. Metlov, Andrei B. Bogatyrëv
Thanks to the recent progress in bulk full three-dimensional nanoscale magnetization distribution imaging, there is a growing interest to three-dimensional (3D) magnetization textures, promising new high information density spintronic applications. Compared to 1D domain walls or 2D magnetic vortices/skyrmions, they are a much harder challenge to represent, analyze and reason about. In this Letter we build analytical representation for such a textures (with arbitrary number of singularity-free hopfions and singular Bloch point pairs) as products of simple quaternionic functions. It can be useful as a language for expressing theoretical models of 3D magnetization textures and specifying a variety of topologically non-trivial initial conditions for micromagnetic simulations.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Pattern Formation and Solitons (nlin.PS)
5 pages, 2 figures
Inverse Design of Amorphous Materials with Targeted Properties
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Jonas A. Finkler, Yan Lin, Tao Du, Jilin Hu, Morten M. Smedskjaer
Disordered (amorphous) materials, such as glasses, are emerging as promising candidates for applications within energy storage, nonlinear optics, and catalysis. Their lack of long-range order and complex short- and medium-range orderings, which depend on composition as well as thermal and pressure history, offer a vast materials design space. To this end, relying on machine learning methods instead of trial and error is promising, and among these, inverse design has emerged as a tool for discovering novel materials with desired properties. Although inverse design methods based on diffusion models have shown success for crystalline materials and molecules, similar methods targeting amorphous materials remain less developed, mainly because of the limited availability of large-scale datasets and the requirement for larger simulation cells. In this work, we propose and validate an inverse design method for amorphous materials, introducing AMDEN (Amorphous Material DEnoising Network), a diffusion model-based framework that generates structures of amorphous materials. These low-energy configurations are typically obtained through a thermal motion-driven random search-like process that cannot be replicated by standard denoising procedures. We therefore introduce an energy-based AMDEN variant that implements Hamiltonian Monte Carlo refinement for generating these relaxed structures. We further introduce several amorphous material datasets with diverse properties and compositions to evaluate our framework and support future development.
Materials Science (cond-mat.mtrl-sci)
Antiferromagnetic resonance and two-magnon absorption in an XXZ-chain antiferromagnet Cs2CoCl4
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
Magnetic excitations of the exchange-dipole quasi 1D XXZ antiferromagnet are studied in the ordered phase. We observe a transformation of the electron spin resonance (ESR) spectrum when crossing the Néel temperature near 0.2 K. The single-mode ESR of a correlated XXZ chain transforms in the multi-mode spectrum in the ordered phase. The multi-mode spectrum consists mainly of the intensive mode of a single correlated chain, which is surrounded and/or indented by numerous weak satellites. The number of securely fixed modes is eight at magnetic field parallel b-axis and twelve at magnetic field parallel a-axis. Besides of the multi-mode resonance observed at the transverse polarization of the microwave and static magnetic fields, we reveal a wide band of absorption by (k,-k)- pairs of quasiparticles at the longitudinal polarization. This kind of absorption of microwaves occurs both in the ordered and specific spin-liquid phases, revealing the presence of quasiparticles in the specific spin-liquid phase.
Strongly Correlated Electrons (cond-mat.str-el)
11 pages, 9 figures
Persistent Fluctuating Superconductivity and Planckian Dissipation in Fe(Te,Se)
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Jonathan Stensberg, Pok Man Tam, Xiaoyu Yuan, Xiong Yao, Heshan Yu, Chih-Yu Lee, An-Hsi Chen, Philip J.D. Crowley, Matthew Brahlek, Ichiro Takeuchi, Seongshik Oh, Joseph Orenstein, Charles Kane, Liang Wu
Increasingly intricate phase diagrams in new classes of superconductors host fascinating interactions between superconductivity, diverse quantum phases, and quantum critical dynamics. The native superfluids, however, often exhibit much lower density and much greater inhomogeneity than conventional superfluids. This may render the superconductivity susceptible to fluctuations that are ordinarily assumed to be frozen out far below the superconducting transition temperature $ T_c$ , calling into question the degree to which the superconducting state is fully coherent. In this work, we leverage terahertz spectroscopy to demonstrate strongly fluctuating superconductivity in topological compositions of the multiband iron-based superconductor Fe(Te,Se). These fluctuations are found to persist undiminished far below $ T_c$ and converge upon the limit of Planckian dissipation above $ T_c$ . These results indicate that extended quantum fluctuations dominate the electrodynamics of both the superconducting and Planckian-dissipative precursor states of Fe(Te,Se), and demonstrate that the assumption of phase coherence must be rigorously validated in emerging classes of unconventional superconductors.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
6 pages, 8 figures
Low-dimensional Heisenberg magnets: Riemann zeta function regularization
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2025-09-18 20:00 EDT
The Riemann zeta function regularization is employed to extract finite temperature corrections to effective magnetic moment $ S^\ast$ of one- and two-dimensional Heisenberg ferro- and antiferromagnets. Whereas for the one-dimensional ferromagnet we obtain the usual $ T^{1/2}$ spin-wave dependence, for the antiferromagnetic chain the dependence is described by a generalized incomplete Riemann function. The quantity $ S^\ast$ determines strong short-range magnetic order in the absence of long-range order, in particular the correlation length. For the one-dimensional ferromagnet, the results are confirmed by the self-consistent spin-wave theory and Monte Carlo simulations by Takahashi et al.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th)
4 pages
Physics Letters A 561 (2025) 130967
Quantum vs Classical Thermal Transport at Low Temperatures
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-18 20:00 EDT
Zhixing Zou, Jiangbin Gong, Jiao Wang, Giulio Casati, Giuliano Benenti
This work aims to understand how quantum mechanics affects heat transport at low temperatures. In the classical setting, by considering a simple paradigmatic model, our simulations reveal the emergence of Negative Differential Thermal Resistance (NDTR): paradoxically, increasing the temperature bias by lowering the cold bath temperature reduces the steady-state heat current. In sharp contrast, the quantum version of the model, treated via a Lindblad master equation, exhibits no NDTR: the heat current increases monotonically with thermal bias. This marked divergence highlights the fundamental role of quantum effects in low-temperature thermal transport and underscores the need to reconsider classical predictions when designing and optimizing nanoscale thermal devices.
Statistical Mechanics (cond-mat.stat-mech), Quantum Physics (quant-ph)
6+4 pages; comments are welcome
Non-universal Thermal Hall Responses in Fractional Quantum Hall Droplets
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Fei Tan, Yuzhu Wang, Xinghao Wang, Bo Yang
We analytically compute the thermal Hall conductance (THC) of fractional quantum Hall droplets under realistic conditions that go beyond the idealized linear edge theory with conformal symmetry. Specifically, we consider finite-size effects at low temperature, nonzero self-energies of quasiholes, and general edge dispersions. We derive measurable corrections in THC that align well with the experimental observables. Although the quantized THC is commonly regarded as a topological invariant that is independent of edge confinement, our results show that this quantization remains robust only for arbitrary edge dispersion in the thermodynamic limit. Furthermore, the THC contributed by Abelian modes can become extremely sensitive to finite-size effects and irregular confining potentials in any realistic experimental system. In contrast, non-Abelian modes show robust THC signatures under perturbations, indicating an intrinsic stability of non-Abelian anyons.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el), Mathematical Physics (math-ph)
Comment on `High-resolution Measurements of Thermal Conductivity Matrix and Search for Thermal Hall Effect in La$_2$CuO$_4$’
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Shan Jiang, Qiaochao Xiang, Benoît Fauqué, Xiaokang Li, Zengwei Zhu, Kamran Behnia
Recently, Jiayi Hu and co-workers reported that they did not resolve any thermal Hall signal in La$ _2$ CuO$ 4$ by `high resolution’ measurements, setting an upper bound of $ |\kappa{xy}| <2\times 10^{-3}~$ Wm$ ^{-1}$ K$ ^{-1}$ at 20 K. Two points have apparently escaped their attention. First, thermal Hall signals with an amplitude well below this resolution bound have been detected in disordered perovskites. Second, the longitudinal thermal conductivity of their sample is significantly lower than the La$ 2$ CuO$ 4$ sample displaying a thermal Hall signal. We find that a moderate reduction of $ \kappa{xx}$ in SrTiO$ 3$ is concomitant with a drastic attenuation of $ \kappa{xy}$ . A trend emerges across several families of insulators: the amplitude of $ \kappa{xy}$ anti-correlates with disorder.
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other), Superconductivity (cond-mat.supr-con)
Comment on arXiv:2507.21403, 3 pages, 3 figures
Spin-dependent signatures of Majorana modes in thermoelectric transport through double quantum dots
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
We present a comprehensive theoretical analysis of the spin-dependent thermoelectric properties of a double quantum dot system coupled to a topological superconducting nanowire and ferromagnetic leads. The study focuses on the behavior of the Seebeck coefficient and its spin-resolved counterparts, with calculations performed by means of the numerical renormalization group method. We investigate the low-temperature transport regime, where a complex interplay between the two-stage Kondo effect, the ferromagnet-induced exchange field, and the Majorana coupling occurs. We demonstrate that thermoelectric measurements can reveal unique signatures of the Majorana interaction that are challenging to isolate in conductance measurements alone. It is shown that the exchange field fundamentally alters the thermoelectric response, leading to a rich, non-monotonic temperature evolution of the thermopower, which is driven by a temperature-dependent competition between the spin channels. Furthermore, we have identified qualitatively different regimes of spin thermopower generation, controlled by the interplay between the Majorana-induced asymmetry and the spin polarization of the leads. Finally, by connecting the system’s thermoelectric response to the underlying transport asymmetries quantified by the conductance spin polarization, we provide a consistent and unified physical picture, proposing thermoelectric transport as a sensitive probe for Majorana signatures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
12 pages, 7 figures
Field-free transverse Josephson diode effect in altermagnets
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Bijay Kumar Sahoo, Abhiram Soori
We show that altermagnets (AMs) with Rashba spin–orbit coupling can host a transverse Josephson diode effect (TJDE) without any external magnetic field. AMs combine zero net magnetization with spin-polarized Fermi surfaces, enabling the simultaneous breaking of inversion and time-reversal symmetries. We propose a four-terminal Josephson junction where a longitudinal phase bias between opposite superconducting terminals generates transverse supercurrents in the unbiased terminals. These transverse currents exhibit both a diode-like nonreciprocity and a finite anomalous phase offset, revealing a transverse anomalous Josephson effect (AJE). For certain parameter regimes, the transverse current becomes unidirectional, and the TJDE efficiency can exceed 1000%, demonstrating exceptionally strong diode behavior. Remarkably, the magnitude and direction of the TJDE and transverse AJE are tunable by rotating the Néel vector. Our results establish altermagnets as a versatile platform for engineering field-free nonreciprocal superconducting transport in multiterminal devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
6+3 pages, 9+1 figures
From Glaphene to Glaphynes: A Hybridization of 2D Silica Glass and Graphynes
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
Guilherme S. L. Fabris, Raphael B. de Oliveira, Marcelo L. Pereira Junior, Robert Vajtai, Pulickel M. Ajayan, Douglas S. Galvão
Hybrid two-dimensional (2D) materials have attracted increasing interest as platforms for tailoring electronic properties through interfacial design. Very recently, a novel hybrid 2D material termed glaphene, which combines monolayers of 2D silica glass and graphene, was experimentally realized. Inspired by glaphenes, we proposed a new class of similar structures named glaphynes, which are formed by stacking SiO$ _2$ monolayers onto $ \alpha$ -, $ \beta$ -, and $ \gamma$ -graphynes. Graphynes are 2D carbon allotropes with the presence of acetylenic groups (triple bonds). The glaphynes’ structural and electronic properties were investigated using the density functional tight-binding (DFTB) method, as implemented in the DFTB+ package. Our analysis confirms their energetic and structural stability. We have observed that in the case of glaphynes, the electronic proximity effect can indeed open the electronic band gap, but not for all cases, even with the formation of Si-O-C bonds between silica and graphynes.
Materials Science (cond-mat.mtrl-sci)
22 pages and 5 figures
Twist-modulated magnetic interactions in bilayer van der Waals materials
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2025-09-18 20:00 EDT
Tomas T. Osterholt, D. O. Oriekhov, Lumen Eek, Cristiane Morais Smith, Rembert A. Duine
The ability to control magnetic interactions at the nanoscale is crucial for the development of next-generation spintronic devices and functional magnetic materials. In this work, we investigate theoretically, by means of many-body perturbation theory, how interlayer twisting modulates magnetic interactions in bilayer van der Waals systems composed of two ferromagnetic layers. We demonstrate that the relative strengths of the interlayer Heisenberg exchange interaction, the Dzyaloshinskii-Moriya interaction, and the anisotropic exchange interaction can be significantly altered by varying the twist angle between the layers, thus leading to tunable magnetic textures. We further show that these interactions are strongly dependent on the chemical potential, enabling additional control via electrostatic gating or doping. Importantly, our approach is applicable to arbitrary twist angles and does not rely on the construction of a Moiré supercell, making it particularly efficient even at small twist angles.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Intrinsic Resistive Switching in Microtubule-Templated Gold Nanowires for Reconfigurable Nanoelectronics
New Submission | Soft Condensed Matter (cond-mat.soft) | 2025-09-18 20:00 EDT
Borja Rodriguez-Barea, Brenda Palestina Romero, René Hübner, Stefan Diez, Artur Erbe
The scaling limitations of conventional transistors demand alternative device concepts capable of dynamic reconfigurability at the atomic scale. Resistive switching (RS), a key mechanism for neuromorphic computing and non-volatile memory, has been widely demonstrated in oxides, semiconductors, and nanocomposites, but not in pure one-dimensional metallic systems. Here, we report the first electrical characterization of gold nanowires (AuNWs) synthesized within the lumen of functionalized microtubules. Structural analyses confirm continuous metallic wires with local compositional inhomogeneities. Electrical measurements reveal three distinct conduction behaviours and abrupt, reversible resistance transitions under applied bias, consistent with defect-driven electromigration. Voltage pulsing enables active and reproducible modulation of resistance states without loss of metallic conduction, establishing a new RS mechanism intrinsic to pure metallic nanowires. Owing to their high aspect ratio, lateral geometry, and CMOS-compatible processing, microtubule-templated AuNWs provide a versatile platform for reconfigurable interconnects and neuromorphic device architectures.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
23 pages, 15 figures, 1 table
Room temperature reactive sputtering deposition of titanium nitride with high sheet kinetic inductance
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Superconducting thin films with high intrinsic kinetic inductance $ L_{k}$ are important for high-sensitivity detectors, enabling strong coupling in hybrid quantum systems, and enhancing nonlinearities in quantum devices. We report the room-temperature reactive sputtering of titanium nitride thin films with a critical temperature $ T_{c}$ of \SI{3.8}{K} and a thickness of \SI{27}{nm}. Fabricated into resonators, these films exhibit a sheet kinetic inductance $ L_{k, \square}$ of 394$ \textrm{pH}/\square$ , as inferred from resonant frequency measurements. %from this film and measure quality factors of $ 4\times 10^{4}$ ; these quality factors are likely limited by the low resistivity wafer. X-ray diffraction analysis confirms the formation of stoichiometric TiN, with no residual unreacted titanium. The films also demonstrate a characteristic sheet resistivity of 475$ \Omega/\square$ , yielding an impedance an order of magnitude higher than conventional 50~$ \Omega$ resonators. This property could enhance microwave single\textendash photon coupling strength by an order of magnitude, offering transformative potential for hybrid quantum systems and quantum sensing. Furthermore, the high $ L_{k}$ enables Kerr nonlinearities comparable to state\textendash of\textendash the\textendash art quantum devices. Combined with its relatively high $ T_{c}$ , this thin film presents a promising platform for superconducting devices, including amplifiers and qubits operating at higher temperatures.
Superconductivity (cond-mat.supr-con)
Supervised and Unsupervised Deep Learning Applied to the Majority Vote Model
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2025-09-18 20:00 EDT
J. F. Silva Neto, D. S. M. Alencar, L. T. Brito, G. A. Alves, F. W. S. Lima, A. Macedo-Filho, R. S. Ferreira, T. F. A. Alves
We employ deep learning techniques to investigate the critical properties of the continuous phase transition in the majority vote model. In addition to deep learning, principal component analysis is utilized to analyze the transition. For supervised learning, dense neural networks are trained on spin configuration data generated via the kinetic Monte Carlo method. Using independently simulated configuration data, the neural network accurately identifies the critical point on both square and triangular lattices. Classical unsupervised learning with principal component analysis reproduces the magnetization and enables estimation of critical exponents, typically obtained via Monte Carlo importance sampling. Furthermore, deep unsupervised learning is performed using variational autoencoders, which reconstruct input spin configurations and generate artificial outputs. The autoencoders detect the phase transition through the loss function, quantifying the preservation of essential data features. We define a correlation function between the real and reconstructed data, and find that this correlation function is universal at the critical point. Variational autoencoders also serve as generative models, producing artificial spin configurations.
Statistical Mechanics (cond-mat.stat-mech)
11 pages, 9 figures
Characterization of superconducting germanide and germanosilicide films of Pd, Pt, Rh and Ir formed by solid-phase epitaxy
New Submission | Superconductivity (cond-mat.supr-con) | 2025-09-18 20:00 EDT
Hao Li, Zhongxia Shang, Michael P. Lilly, Maksym Myronov, Leonid P. Rokhinson
Facilitated by recent advances in strained Ge/SiGe quantum well (QW) growth technology, superconductor-semiconductor hybrid devices based on group IV materials have been developed, potentially augmenting the functionality of quantum circuits. The formation of highly transparent superconducting platinum germanosilicide (PtSiGe) contacts to Ge/SiGe heterostructures by solid-phase epitaxy between Pt and SiGe has recently been reported, although with a relatively low critical temperature $ <1,\mathrm{K}$ . Here, we present a comparative study of the superconducting properties of Pt, Pd, Rh, and Ir germanides, along with an in-depth characterization of Ir(Si)Ge films formed by solid-phase epitaxy. For films fabricated under optimal epitaxy conditions, we report $ T_\mathrm{c}=3.4,\mathrm{K}$ ($ 2.6,\mathrm{K}$ for IrGe (IrSiGe). High-resolution scanning transmission electron microscopy (HRSTEM) and energy-dispersive X-ray spectroscopy (EDX) reveal that Ir reacts with Ge substrates to form a polycrystalline IrGe layer with a sharp IrGe/Ge interface.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
25 pages, 9 figures
Phonon-assisted photoluminescence of bilayer MoS$_2$ from first principles
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
In indirect band gap materials, phonon-assisted processes are key mechanisms for photoluminescence (PL). Using a first-principles many-body approach, we systematically investigate the phonon-assisted PL in bilayer MoS$ _2$ and its dependence on temperature and external tensile strain. The effects of phonons are accounted for using a supercell approach: we identify the phonon momenta that are important to PL, construct supercells that are commensurate with these phonons, and examine the changes in the optical absorption after explicit displacements of atoms along each phonon mode. The PL intensity is then obtained via the van Roosbroeck-Shockley relationship from the optical absorption spectra. This approach enables us to investigate phonon-absorption and phonon-emission processes separately and how each process depends on temperature. Our results reveal that optical phonons associated with out-of-plane vibrations of S atoms and in-plane vibrations of Mo atoms contribute most to the indirect PL for unstrained bilayer MoS$ _2$ . Additionally, we also discuss how the PL spectra and the phonon contributions evolve with strain. In particular, we show that at high strain, additional phonon channels become available due to the modulation of the electronic band structure.
Materials Science (cond-mat.mtrl-sci)
12 pages, 6 figures
Skyrmion-Antiskyrmion Lattice: A Net-Zero Topological Phase in Low-Symmetry Frustrated Chiral Magnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2025-09-18 20:00 EDT
We report the discovery of a thermodynamically stable skyrmion-antiskyrmion lattice in two-dimensional heterostructures, a novel state exhibiting a net-zero global topological charge owing to an equal population of skyrmions and antiskyrmions. This surprising coexistence of oppositely charged solitons remarkably circumvents their anticipated annihilation. We demonstrate the formation and evolution of this phase in Fe films on C1v -symmetric (110) surfaces of GaAs and CdTe semiconductors. Specifically, we reveal a series of magnetic field-induced phase transitions: cycloidal spin-spiral to skyrmion-antiskyrmion lattice to conical spin-spiral to ferromagnet. The remarkable stability of the net-zero lattice is attributed to symmetry-enforced anisotropic magnetic interactions. Lowering interfacial symmetry to C1v thus enables frustrated chiral magnets, uniquely manifesting in thermodynamically stable net-zero topological soliton lattices, as revealed by our findings.
Materials Science (cond-mat.mtrl-sci)