CMP Journal 2026-09-11
Statistics
Nature Physics: 1
Physical Review Letters: 18
Physical Review X: 2
Review of Modern Physics: 1
arXiv: 74
Research Square: 2
Nature Physics
Digital quantum simulations of scattering in quantum field theories using W states
Original Paper | Quantum simulation | 2026-09-10 20:00 EDT
Roland C. Farrell, Nikita A. Zemlevskiy, Marc Illa, John Preskill
High-energy particle collisions can convert energy into matter through the inelastic production of new particles. Quantum computers offer a route to simulating these out-of-equilibrium processes, but accessing post-collision dynamics and determining the abundance of produced particles remain challenging. Here we report evidence for inelastic particle production in one-dimensional Ising field theory using a digital quantum processor. We collide two wavepackets, each containing the lightest particle in the theory, and use the skewness of the measured energy density to identify an inelastic component containing one outgoing light particle and one heavier particle. The experiment uses 104 qubits and up to 5,589 two-qubit gates to access the post-collision dynamics. The computation relies on a quantum algorithm that extends protocols for efficiently creating W states–multipartite entangled states with a single excitation distributed across many qubits–to prepare the initial wavepackets. With mid-circuit measurements followed by operations conditioned on their outcomes, the circuit depth is independent of the wavepacket’s spatial volume, rather than scaling polynomially as in previous methods. We construct wavepacket-preparation circuits for one-dimensional Ising and scalar field theories, the Schwinger model and two-dimensional Ising field theory.
Quantum simulation, Theoretical particle physics
Physical Review Letters
Precision Measurement of the Muon Charge Asymmetry from $W$-Boson Decays in $pp$ Collisions at $\sqrt{s}=13\text{ }\text{ }\mathrm{TeV}$ in the Forward Region
Article | Particles and Fields | 2026-09-10 06:00 EDT
R. Aaij et al. (LHCb Collaboration)
A precision measurement of the muon charge asymmetry from -boson decays in proton-proton collisions at is presented. The analysis utilizes data corresponding to an integrated luminosity of , recorded by the LHCb detector during 2016, 2017, and 2018. The asymmetry is measured for …
Phys. Rev. Lett. 137, 111801 (2026)
Particles and Fields
Muonium Spectroscopy as a Quantum Sensor for Axion Dark Matter
Article | Particles and Fields | 2026-09-10 06:00 EDT
Feng Fang, Kim Siang Khaw, Ce Zhang, Qiaoli Yang, Liangwen Chen, Jie Yang, Lei Yang, and Zhiyu Sun
High-intensity muon beams could enable a muonium-based axion search through resonant quantum transitions between hyperfine states. Combining theoretical calculations with simulation results, we demonstrate that such a muonium-based experimental approach could complement and tighten constraints on th…
Phys. Rev. Lett. 137, 111803 (2026)
Particles and Fields
Measured and Theoretical $\mathrm{K}α$ X-Ray Emission Linewidths of U, Np, and Pu
Article | Atomic, Molecular, and Optical Physics | 2026-09-10 06:00 EDT
Abigail Wessels, Jonathan W. Dean, Daniel T. Becker, Douglas A. Bennett, Matthew H. Carpenter, Mark Croce, Joseph W. Fowler, Johnathon D. Gard, Paul Indelicato, Katrina E. Koehler, J. A. B. Mates, Daniel McNeel, David Mercer, Daniel R. Schmidt, Katherine Schreiber, Daniel S. Swetz, Duc Vo, Sophie Weidenbenner, and Joel N. Ullom
We present measurements of the and natural x-ray linewidths of uranium, neptunium, and plutonium (, 93, 94) obtained using a superconducting transition-edge sensor microcalorimeter array. The relative uncertainties range from 0.5% to 1.5%, improving upon previous values by factors rangin…
Phys. Rev. Lett. 137, 113001 (2026)
Atomic, Molecular, and Optical Physics
Bound States in the Continuum with Vectorial Topological Charge
Article | Atomic, Molecular, and Optical Physics | 2026-09-10 06:00 EDT
Wen-Jin Zhang, Ze-Peng Zhuang, Xiao-Dong Chen, and Jian-Wen Dong
Bound states in the continuum (BICs) have long been recognized as topological singularities of light, yet their descriptions have relied solely on scalar topological charges that trace a polarization angle rotation, leaving their true vectorial topology unexplored. Here, we apply the concept of a ve…
Phys. Rev. Lett. 137, 113803 (2026)
Atomic, Molecular, and Optical Physics
Anomalous Statistics of Sea Ice Transport are Explained by Collisional Rules
Article | Physics of Fluids, Earth & Planetary Science, and Climate | 2026-09-10 06:00 EDT
Bryan Shaddy, P. Alex Greaney, and Bhargav Rallabandi
Arctic sea ice fluctuates in response to its turbulent environment, leading to dispersion behaviors that are not well understood. We resolve this gap using simulations that model sea ice as a granular medium that responds to stochastic winds. Using only directly measured local environmental and ice …
Phys. Rev. Lett. 137, 114201 (2026)
Physics of Fluids, Earth & Planetary Science, and Climate
High-Energy-Density Plasma Nanorod by Collisionless Absorption of Ultrafast Laser Pulse Inside Dielectrics
Article | Plasma and Solar Physics, Accelerators and Beams | 2026-09-10 06:00 EDT
Kazem Ardaneh, Remi Meyer, Mostafa Hassan, Remo Giust, Chen Xie, Benoit Morel, Ismail Ouadghiri-Idrissi, Luca Furfaro, Luc Froehly, Arnaud Couairon, Guy Bonnaud, and Francois Courvoisier
The generation of energetic and dense plasmas by femtosecond laser pulses within the bulk of solids can pave the way to study warm dense matter, shocks, extreme UV radiation, or the synthesis of new material phases. However, this has remained elusive because of the intrinsic dynamical effects of def…
Phys. Rev. Lett. 137, 115101 (2026)
Plasma and Solar Physics, Accelerators and Beams
Generalized Lawson-Cordey-Mills Accessibility of Fusion Ignition
Article | Plasma and Solar Physics, Accelerators and Beams | 2026-09-10 06:00 EDT
Luis F. Delgado-Aparicio, Masayuki Ono, and Jonathan E. Menard
A generalized ignition-accessibility framework is developed that unifies Lawson power balance, Cordey accessibility, the marginal ignition ridge, ignition entry points, and Mills thermal-runaway dynamics into a single self-consistent description of reactor-relevant burning plasmas. The 0D analysis r…
Phys. Rev. Lett. 137, 115102 (2026)
Plasma and Solar Physics, Accelerators and Beams
Observation of Individual Vortex Penetration in a Coplanar Superconducting Resonator
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Kirill Shulga, Shunsuke Nishimura, Pavel A. Volkov, Miu Hirano, Toshiaki Inada, Ryota Hasegawa, Takeyuki Tsuji, Takayuki Iwasaki, Mutsuko Hatano, Kento Sasaki, and Kensuke Kobayashi
A coplanar superconducting resonator makes possible the direct observation of the real-time entry of individual Abrikosov vortices.
Phys. Rev. Lett. 137, 116001 (2026)
Condensed Matter and Materials
Superconductivity in Noncentrosymmetric Rhombohedral ${\mathrm{NbSe}}_{2}$
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Zhengxian Li, Xiaoyu Shen, Shaozheng Wang, Kai Liu, Yating Sha, Tianyang Wang, Feng Liu, Qingchen Duan, Kenji Watanabe, Takashi Taniguchi, Peng Chen, Shiyong Wang, Ruidan Zhong, Dong Qian, Yufan Li, Shengwei Jiang, Noah F. Q. Yuan, and Guorui Chen
Crystal stacking offers a powerful yet underexplored route to engineer symmetry in layered superconductors. Here we report superconductivity in rhombohedral-stacked (), a noncentrosymmetric polytype in which global inversion symmetry is removed by stacking alone. Using comprehensive st…
Phys. Rev. Lett. 137, 116002 (2026)
Condensed Matter and Materials
Polaronic Lattice State Hybridization in Reduced Oxide Surface Reconstructions
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Ning Xu, Sergey V. Levchenko, Yong Wang, and Zhong-Kang Han
Reduced oxide surfaces often undergo complex reconstructions in which atomic rearrangements and reduction-induced electronic redistribution are strongly coupled, obscuring the electronic principles that govern their stability. Here, we address this problem on the prototypical rutile surfac…
Phys. Rev. Lett. 137, 116201 (2026)
Condensed Matter and Materials
Nanomechanical Detection of Vortices in an Electron Fluid
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Andrey A. Shevyrin, Askhat K. Bakarov, and Arthur G. Pogosov
A nanomechanical resonator provides a simple way to directly measure the torque generated by electron vortices.
Phys. Rev. Lett. 137, 116302 (2026)
Condensed Matter and Materials
Superballistic Transport of Thermal Photons in Confined Many-Body Systems
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Jian Dong, Junming Zhao, Philippe Ben-Abdallah, and Linhua Liu
Ballistic transport is traditionally regarded as a limiting regime for scattering-free energy transfer. Here, we predict a superballistic radiative heat transport regime that surpasses this limit in dilute chains of plasmonic nanoparticles confined within cavities. This anomalous regime exhibits sup…
Phys. Rev. Lett. 137, 116303 (2026)
Condensed Matter and Materials
Emergent Surface Altermagnetism
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Yuzhong Hu, Pan Zhou, Baoru Pan, Songmin Liu, Binchang Zhou, and Lizhong Sun
Research on altermagnetism has thus far primarily focused on spin-polarized bulk electronic states in magnetic materials. In this work, we advance the field by introducing the concept of surface altermagnetism (SAM), wherein altermagnetic spin polarization emerges at the surfaces of collinear antife…
Phys. Rev. Lett. 137, 116705 (2026)
Condensed Matter and Materials
Strong Coupling between Propagating Spin Waves and Microwave Photons in a Superconducting Resonator
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Yi Li, Jinho Lim, Xingzhi Wang, Tomas Polakovic, Carissa Kiehl, Moojune Song, Phuoc Cao Van, Ralu Divan, Ulrich Welp, Charudatta Phatak, Jong-Ryul Jeong, Kab-Jin Kim, Jian-Min Zuo, Axel Hoffmann, and Valentine Novosad
We demonstrate strong coupling between propagating spin-wave modes and microwave photons in superconducting resonator-magnetic thin film hybrid circuits. By fabricating the resonator directly on yttrium iron garnet thin films grown on rare-earth-free substrates, we achieve strong couplin…
Phys. Rev. Lett. 137, 116706 (2026)
Condensed Matter and Materials
Generalized Theory of Domain-Wall Width in Multisublattice Heisenberg Magnets
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
José M. Lendínez, Marta Yanguas, Theodor Griepe, Michael Saur, Rubén M. Otxoa, Levente Rózsa, and Unai Atxitia
We propose a general expression for the domain-wall width in generic multisublattice Heisenberg magnets with collinear order and uniaxial anisotropy, applicable to ferro-, antiferro-, and ferrimagnetic orders. The result follows from an exact connection between the domain-wall profile and the long-w…
Phys. Rev. Lett. 137, 116707 (2026)
Condensed Matter and Materials
Chiral High-Harmonic Generation via Subcycle Symmetry Engineering
Article | Condensed Matter and Materials | 2026-09-10 06:00 EDT
Ya Bai, Hanqing Xu, Ying Ma, Shuo Wang, Jingyuan Niu, Candong Liu, Peng Liu, and Ruxin Li
A crystal with special geometric properties can be optically driven to produce an output beam with any desired polarization.
Phys. Rev. Lett. 137, 116905 (2026)
Condensed Matter and Materials
Self-Organized Hyperuniformity in a Minimal Model of Population Dynamics
Article | Statistical Physics; Classical, Nonlinear, and Complex Systems | 2026-09-10 06:00 EDT
Tal Agranov, Natan Wiegenfeld, Omer Karin, and Benjamin D. Simons
A minimal model of population dynamics provides an organic pathway to hyperuniformity that relies on natural competition rather than fine-tuned dynamics and rigid conservation laws.
Phys. Rev. Lett. 137, 117401 (2026)
Statistical Physics; Classical, Nonlinear, and Complex Systems
Extent of Nonequilibrium Sets Relaxation Barriers in Dewetting Polymer Films
Article | Polymers, Chemical Physics, Soft Matter, and Biological Physics | 2026-09-10 06:00 EDT
Mithun Madhusudanan, Federico Caporaletti, Jotypriya Sarkar, Rohit V. Menon, Sivasurender Chandran, Ronald P. White, Jane E. G. Lipson, Simone Napolitano, and Mithun Chowdhury
Thin polymer films are archetypal nonequilibrium systems in which chain conformations are frozen by rapid preparation. The resulting molecular recoiling stress drives the system toward equilibrium and relaxes with time and temperature. We show that the activation energy governing this relaxation dep…
Phys. Rev. Lett. 137, 118102 (2026)
Polymers, Chemical Physics, Soft Matter, and Biological Physics
Physical Review X
Quantum Birthmarks: Ergodicity Breaking Beyond Scarring
Article | 2026-09-10 06:00 EDT
Anton M. Graf, Saul Atwood, Mingxuan Xiao, Roland Ketzmerick, Eric J. Heller, and Joonas Keski-Rahkonen
Researchers develop a theoretical framework showing that quantum systems permanently retain a memory of their initial state and early dynamics, in defiance of classical expectations.
Phys. Rev. X 16, 031063 (2026)
Effective Ionic Valence and Local Magnetic Moment in Kagome Superconductors
Article | 2026-09-10 06:00 EDT
Ruoshi Jiang, Zi-Jian Lang, Yuzki Oey, Andrea Capa Salinas, Stephen D. Wilson, Yongwei Li, Ilya Shipulin, Yiwen Zhang, Deng Hu, Zhiwei Wang, Hans-Henning Klauss, Zurab Guguchia, Vadim Grinenko, and Wei Ku
Revealing concealed ionic local moments in kagome superconductors reflects strong local correlations.
Phys. Rev. X 16, 031064 (2026)
Review of Modern Physics
Opinion dynamics: Statistical physics and beyond
Article | Condensed matter | 2026-09-10 06:00 EDT
Michele Starnini, Fabian Baumann, Tobias Galla, David Garcia, Gerardo Iñiguez, Márton Karsai, Jan Lorenz, and Katarzyna Sznajd-Weron
Social systems, when considered on an appropriately coarse-grained scale, display phenomena reminiscent of the behavior of physical many-body systems and can be studied using the methods of statistical mechanics. A particularly interesting subfield is opinion dynamics, which aims to understand the emergence of collective social phenomena, such as consensus, polarization, and fragmentation. This review systematizes the terminology and methods of opinion dynamics, surveys empirical findings alongside theoretical models, and summarizes the current state and future directions of this field.
Rev. Mod. Phys. 98, 035004 (2026)
Condensed matter
arXiv
Generating is not discovering: a pre-registered physics judge for AI-proposed superconductors, calibrated on six known superconductors and one negative control
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-11 20:00 EDT
Generative models now propose millions of “stable” crystal structures, and their own referees have shown that stability is not discovery; no public benchmark asks whether a candidate has the physics to do a job. For superconductors the job is twofold: to pair, with a definite gap symmetry, and to become wire. We present a physics judge that answers both from a structure alone (DFT+U, a gated Wannier model, the full rank-4 RPA susceptibility on a $ 24^3$ mesh, the linearized gap equation, an irreducible-representation classifier, a manufacturability funnel) and measure what it says about what generators propose. With answer keys pre-registered before computing, the judge was calibrated on six known superconductors (Nb, Nb$ _3$ Sn, MgB$ _2$ , BaFe$ _2$ As$ _2$ , La$ _{2-x}$ Sr$ _x$ CuO$ _4$ , YBa$ _2$ Cu$ _3$ O$ _7$ ), recovering the expected class in all six after two dated corrections. On the ruthenium analogue of the iron pnictide, with two runs and their criterion pre-registered the day before, it returns a null verdict at the same physical interaction where iron gives s$ \pm$ ($ \lambda_1 \le 0.0007$ versus 0.096; critical U 4.17 versus 0.97 eV); the pre-registered equal-alpha run fails the letter of the criterion, and we declare the resolution in favour of absolute U as post-hoc. The funnel reproduces the industrial map with thresholds fixed before running. Three generation audits follow: a descriptor sweep over 150 Materials Project metals re-finds the canon; 1,248 MatterGen structures yield 0 candidates that are new, stable and carry a pairing motif; mechanism filters over 47,893 compounds, validated by a blind hold-out, re-derive the community’s analogies: geometry plus d-count is necessary but not sufficient. Generation re-finds what is known; judgment is the bottleneck. We propose a public benchmark over the eleven lists of AI-proposed superconductor candidates, none of which classifies gap symmetry.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
12 pages, 3 figures. Data, dated pre-registrations and supplementary tables S1-S7 at this https URL
Geometric Ginzburg-Landau theory of charge ordering and commensurability
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Aneesh Agarwal, Rutvij Gholap, Mohammad Saeed Bahramy, Robert-Jan Slager
The concept of quantum geometry has recently led to reinvigorated insights in a wide range of fields including physical responses, superconductivity, and optical transitions, with effects most pronounced in systems with nearly flat dispersion. Here, we show that it plays an essential role in charge density wave formation (CDW) – an important physical phenomenon that is responsible for driving various sharp changes in material transport properties including metal-insulator transitions. We derive an effective Ginzburg-Landau theory including uncharted contributions and, as a highlight, discover a general criterion for both CDW formation and commensurability transitions where underlying electron-phonon interactions manifest purely as electronic quantum geometric enhancements/suppressions. We benchmark our framework in a class of transition-metal dichalcogenides and resolve a longstanding puzzle where well-established purely kinetic CDW criteria fail in describing the correct ordering wavevector. Besides rendering robust criteria and fundamental insights that are immediately relevant to several experimental charge ordering systems, our theory can also be applied directly to other phonon-mediated phases such as superconductivity, and can be used as an important tool to explore the interplay between various such states. More generally, our framework provides a recipe for investigating the role of quantum geometry in phase transitions.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
12+5 pages, 4+4 figures
Lattice 2-group symmetries: operators, defects, and gauging
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Lucas Z. Brito, Salvatore D. Pace
We construct and study lattice realizations of finite 2-group symmetries in $ {2+1}$ d quantum lattice systems with finite-dimensional tensor-product Hilbert spaces. We focus on two broad classes of 2-groups with 0-form symmetry group $ G$ and 1-form symmetry group $ A$ : split 2-groups with trivial Postnikov class $ {[\beta]\in\mathcal{H}^3(G,A)}$ , and central 2-groups with trivial action $ {\rho\colon G\to\text{Aut}(A)}$ . In both cases, we construct symmetry operators on the full tensor-product Hilbert space that become 2-group symmetry operators when restricted to the topological subspace of the lattice $ A$ 1-form symmetry. While the lattice split 2-group symmetry operators are onsite, the lattice central 2-group symmetry operators are not, and can only be made onsite after introducing ancillae. We extensively explore various manifestations of $ \rho$ and $ [\beta]$ for these lattice 2-group symmetry operators and demonstrate their agreement with expectations from quantum field theory. These manifestations arise in the transformation of operators carrying symmetry charge, the structure of lattice 2-group symmetry defects, and the dual fusion 2-category symmetries obtained by gauging the lattice 2-group symmetries. We further propose families of local symmetric Hamiltonians for both classes of lattice 2-group symmetries and identify exactly solvable limits lying in phases with spontaneous 2-group symmetry breaking and nontrivial symmetry-enriched topological order. In one such limit, the gauged Hamiltonians are exactly solvable lattice realizations of the corresponding 2-group gauge theories, whose ground-state degeneracies we calculate.
Strongly Correlated Electrons (cond-mat.str-el), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
47 pages + appendices
Quantum interference between vortex- and impurity-bound states boosts thermoelectricity
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-11 20:00 EDT
Thermoelectric effects in superconductors are generally suppressed by the approximate particle-hole symmetry of the quasiparticle spectrum, but can become pronounced near defects that host particle-hole asymmetric bound states. Here, we investigate how the local thermoelectric response is modified when multiple vortices or nonmagnetic impurities are brought into proximity. Using a lattice Bogolioubov-de Gennes approach combined with linear-response tunneling theory, we calculate the spatially resolved density of states and Seebeck coefficient in $ s$ - and $ d$ -wave superconductors. We find that the thermoelectric response can be strongly enhanced when spatially extended defect-induced states overlap. For vortices, this enhancement persists beyond the immediate core regions and originates from interference between vortex-bound states. For impurities, the thermoelectric response exhibits a comparable dependence on impurity separation in the $ s$ - and $ d$ -wave cases, although the associated spectral reconstruction is considerably more localized in the $ s$ -wave superconductor. Our results show that the spatial extent and interference of defect-induced quasiparticle states provide a means of controlling local thermoelectricity in inhomogeneous superconductors, with potential relevance for cryogenic thermoelectric sensing and energy conversion.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
8 pages, 7 figures
Dissipative quantum mechanics of Andreev bound states
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-11 20:00 EDT
Mikhail S. Kalenkov, Andrei D. Zaikin
We propose a microscopic scheme that allows to describe ac Josephson effect in superconducting junctions in terms of dissipative quantum dynamics of subgap Andreev bound states. This approach is particularly useful for highly transparent junctions at subgap bias voltages in which case a non-trivial combination of Landau-Zener tunneling between Andreev levels and their instability due to quasiparticle escape into continuum may play an important role. In the low bias regime, we evaluate the non-equilibrium current-phase relation of superconducting junctions at arbitrary transmissions and identify a sub-Ohmic phase-dependent dissipative contribution to the current controlled by quasiparticle dynamics near the superconducting gap edge.
Superconductivity (cond-mat.supr-con)
16 pages, 7 figures
A Unified Theory of Collective Magnon and Orbiton Excitations in Altermagnets
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Bishal Das, Chanchal K. Barman, Aftab Alam
Altermagnetism has recently emerged as a distinct collinear magnetic phase exhibiting momentum-dependent spin-splitting despite vanishing net magnetization, as a consequence of inequivalent non-magnetic environments. Lately, it has been proposed that strong electronic correlations may yield spontaneous altermagnetism due to orbital ordering even for equivalent non-magnetic environments. While previous studies have largely focused on the electronic structure, a unified understanding of the collective excitations associated with these two different microscopic mechanisms stabilizing altermagnetism remains absent. Here, we develop an extended Kugel’-Khomskiĭ spin-orbital model on a decorated square lattice that simultaneously incorporates inequivalent non-magnetic environments and correlation-driven orbital ordering within a common theoretical framework. Employing a self-consistent mean-field spin-wave orbital-wave formalism, we demonstrate the emergence of mutually unhybridized but interdependent magnon and orbiton excitations exhibiting characteristic chiral-splitting. We show that the splitting originates from two distinct microscopic contributions: a lattice-dependent term arising from inequivalent non-magnetic environments and an orbital-order-induced exchange-anisotropy term that survives even for equivalent non-magnetic environments. The proposed framework therefore unifies the collective excitations associated with both types of altermagnetism. We further investigate the finite-temperature evolution of the coupled spin-orbital system, revealing the breakdown of spin-wave and orbital-wave approximations through spurious 1st-order transitions, while complementary classical Monte Carlo simulations recover the expected continuous 2nd-order behaviour. Our work establishes a unified microscopic framework for understanding collective magnon and orbiton excitations in altermagnets.
Strongly Correlated Electrons (cond-mat.str-el), Other Condensed Matter (cond-mat.other), Quantum Gases (cond-mat.quant-gas), Mathematical Physics (math-ph), Quantum Physics (quant-ph)
37 pages (19 pages main, 18 pages supplement), 5 figures (all in main), 1 table (in main)
Moiré Topology in Twisted Structures with Noncollinear Spin-Orbit Coupling
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Xilong Xu, Liangtao Peng, Shaffique Adam, Li Yang
Moiré superlattices provide a powerful platform for flat bands and correlated topological phases, yet most established examples rely on valley-contrasting Berry curvature in hexagonal lattices. Here, we propose a different route to achieve topological moiré minibands based on noncollinear spin orbit coupling in centrosymmetric type II SOC bilayers. Interlayer hybridization opens local pseudogaps and produces sharply localized Berry curvature, which twisting reconstructs into isolated topological minibands without requiring valley degrees of freedom or hexagonal symmetry. We demonstrate this mechanism in tetragonal Dresselhaus-SOC HgI2, where a Lieb-like moiré potential yields topological flat bands. To improve miniband isolation, we develop a physics-informed machine-learning surrogate that identifies stronger SOC as a key design principle and guides the replacement of Hg by Pb. The resulting PbI2 minibands are narrower and better isolated, supporting correlation-driven magnetism and tunable quantum spin Hall and Chern insulating phases, thereby providing an optimized material realization for experimental exploration.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
21 pages, 5 figures
Nano Lett. 26, 10356 (2026)
Consensus in Effective Model Inference for Disordered Ising Systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
When independent learners are trained on data from the same disordered system, finite and noisy samples can lead them to different descriptions of the underlying physics. We quantify the reproducibility of such descriptions through consensus, the degree of agreement among independently trained models. In a teacher-student framework on the two-dimensional random-bond Ising model, an ensemble of students each infers a single uniform effective coupling from a finite set of equilibrium configurations drawn from one quenched bond realization. Aggregating the inferred couplings across students and realizations yields the consensus distribution, whose width quantifies the agreement among learners. The variance of this distribution separates exactly into a finite-sampling contribution, bounded below by inverse of Fisher information, and a quenched-disorder contribution. Sum of these two variance is minimized near critical region, so the consensus width has a minimum near the pseudocritical temperature that sharpens with increasing disorder. The two minima arise from different mechanisms: the sampling term inherits the critical peak of the Fisher information, while the disorder term is temperature-independent at leading order and acquires its critical minimum only at fourth order in the disorder strength, through the covariance between the linear and cubic responses to the bond disorder. Because the students fit a uniform coupling to a heterogeneous lattice, the inferred coupling also carries a misspecification bias that survives in the infinite-data limit. This bias displaces the minimum of the mean-squared error above the consensus minimum, so the temperature at which independent learners agree most closely is not the temperature at which their shared answer is most faithful.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn)
18 pages, 6 figures
Thermal Stability of Encapsulated Molecular Structures with Extended OH-Hydrogen-Bond Chains
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Using a coarse-grained model, we performed numerical simulations of the dynamics of linear molecular chains adsorbed on a flat substrate (on the surface of an h-BN crystal). It is shown that molecules containing benzene rings and hydroxyl groups in their structure can form stable hydrogen-bond chains OH$ \cdots$ OH$ \cdots$ OH. Such chains can be formed by phenol C$ _6$ H$ _5$ OH, 4-phenylphenol C$ _6$ H$ _5$ –C$ _6$ H$ _4$ OH, paracetamol CH$ _3$ C(O)NHC$ _6$ H$ _4$ OH, and 4-hydroxybenzanilide C$ _6$ H$ _5$ C(O)NHC$ _6$ H$ _4$ OH molecules. The dissociation of these chains occurs at temperatures above $ T_1=190$ , 240, 300, and 400K, respectively. Coating such molecular systems with a hexagonal boron nitride sheet (their van der Waals encapsulation) significantly enhances their thermal stability. Such encapsulated molecular structures retain hydrogen-bond chains up to temperatures of $ T_2=470$ , 800, 880, and 1140K, respectively. The simulations allow us to conclude that h-BN-encapsulated chains of these molecules can be used to create anhydrous proton-exchange membranes capable of operating at high temperatures. The most promising are encapsulated chains of paracetamol and 4-hydroxybenzanilide molecules.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
13 pages, 15 figures, 5 tables
On the physical origins of switching diversity in Cu-embedded SiO$_x$ memristive devices
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Sahitya Yarragolla, Rouven Lamprecht, Tobias Gergs, Ole Gronenberg, Hermann Kohlstedt, Thomas Mussenbrock, Jan Trieschmann
Resistive switching devices with sub-stoichiometric SiO$ _x$ and pancake-like Cu nanoparticles (Cu-PCs) exhibit distinct macroscopic current-voltage characteristics classified as capacitive or gradual (interface-type switching) and abrupt or resistive (filamentary-type switching), motivating an analysis of the microscopic processes underlying this diversity. It is proposed that the device defect landscape is largely shaped by two charged defect types, mobile oxygen vacancies and immobile Cu-related defects, whose distributions jointly govern interfacial and bulk transport. An effective one-dimensional cloud-in-a-cell simulation framework is employed to reproduce the phenomenological picture of both interface-type and filamentary-type switching by incorporating the dominant coupled ionic and electronic processes underlying these mechanisms. The model includes oxygen-vacancy drift-diffusion, Schottky-limited injection at the metal/oxide interfaces, and bulk trap-assisted transport via Poole-Frenkel conduction, with Cu-PCs near the top interface treated effectively. A simulation-based parametric study varying voltage stress, sweep rate, and oxide thickness is used to examine how these factors rebalance voltage partitioning and the spatiotemporal electric field distribution, thereby altering vacancy redistribution and the relative contributions of interface- and bulk-limited conduction. Using representative, physically motivated parameter sets informed by prior device-level studies, the simulations accurately reproduce the characteristic $ I$ -$ V$ signatures of seven different experimentally observed switching responses. Overall, the findings help to link microscopic defect landscapes and transport processes to experimentally measured macroscopic responses within a single, self-consistent modeling framework.
Materials Science (cond-mat.mtrl-sci)
20 pages, 10 figures, Supplementary Information included at the end of the same PDF
Dissipation-induced nonlocal phase-coherent transport in a topological superconductor
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
S. V. Aksenov, M. S. Shustin, I. S. Burmistrov
Nonlocal phase-coherent transport via Majorana bound states, so-called teleportation, requires Coulomb blockade to suppress local Andreev reflection. We show that dissipation can replace the need for Coulomb blockade. We study a Kitaev chain coupled to a Markovian bath and identify a regime where the magnitude of nonlocal conductance contribution reach the local one. In this regime, the lowest-energy subspace is maximally mixed, reminiscent of a directly-grounded nontrivial topological superconductor. Phase coherence is confirmed by Aharonov-Bohm oscillations. Our results establish dissipation as a tool for controlling quantum teleportation in Majorana systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 4 figures
Controlling topology in flux-mismatched Hofstadter bilayers
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Stacked two-dimensional materials provide a promising platform for electrically controlling topological electronic states. However, tunneling between layers hybridizes their bands and removes the crossings needed to change topology. We show that this does not always have to be the case. Band crossings and associated Weyl points are topologically enforced in Hofstadter bilayers whose layers experience different magnetic fluxes. When resonant magnetic Bloch multiplets carry unequal Chern numbers, their projected tunneling is topologically obstructed and must vanish at isolated momenta. Sweeping the layer bias through these zeros creates synthetic Weyl monopoles in momentum-bias space that transfer the Chern mismatch. We demonstrate two consequences: a direct transition between insulating Chern phases and a reentrant compensated metal in which Lifshitz transitions bound the metallic window while internal Weyl events reconstruct the band topology. Consequently, the fixed-filling Hall response remains continuous and nonquantized even as integer Chern number is transferred between bands. Berry-flux, TKNN, and interface calculations independently verify the mechanism and its multichannel chiral signature. We outline realizations in Moire and anomalous-Hall heterostructures, establishing flux mismatch as an experimentally accessible route to electrically programmable Chern phases and chiral transport.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
9 pages, 7 figures
Competing Interlayer Loop Currents and Superconductivity in the Bilayer $t$-$J_\perp$-$V$ Model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Luciano Zinni, Fabricio Gómez, Jun Zhan, Mat'ıas Bejas, Xianxin Wu, Andreas P. Schnyder, Andrés Greco
The recent discovery of high-$ T_c$ superconductivity in pressurized and thin-film bilayer nickelates, featuring a strong interlayer exchange coupling, and their potential similarities with cuprate superconductors, has made this a very active topic in condensed matter physics. In the present paper we study the strongly correlated one-orbital ($ d_{x^2-y^2}$ ) bilayer $ t$ -$ J_\perp$ -$ V$ model for nickelates, where $ V$ denotes the Coulomb interactions, using a controlled large-$ N$ expansion at and beyond the mean-field level. Focusing on the out-of-plane spin exchange interaction ($ J_\perp$ ), we find that it triggers both out-of-plane $ s$ -wave superconductivity and an out-of-plane bond-order phase ($ z$ -BOP) instability. The $ z$ -BOP gives rise to a complex $ z$ -axis hopping dominated by its imaginary component, which drives out-of-plane currents and induces in-plane ones, spontaneously forming on the vertical plaquettes a loop-current state that breaks time-reversal symmetry. Competition between this loop-current phase and superconductivity yields a dome-shaped superconducting region, with optimal superconductivity occurring near the $ z$ -BOP quantum critical point. The resulting phase diagram features a pure loop-current region, a low-doping coexistence phase, a pure superconducting state at higher doping, and a correlated metallic state.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
Hyperspin Altermagnets
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Hai-Yang Ma, Yuanchang Li, Hu Xu, Shengbai Zhang, Jin-Feng Jia
The behavior of spin quantum in k-space is key to identifying altermagnets (AMs) as the third kind of fundamental collinear magnetism. In contrast, non-collinear magnets,though abundant in nature,lack well-defined spin quantum numbers, and the resulting spin textures are often highly complex, which limits their potential for next-generation spintronic applications. Here we propose hyperspin, which lives in a higher-dimensional space, to address these drawbacks. Through analyzing the commutation relations between spin and Hamiltonian for a class of non-collinear magnets, we reveal it is a hyperspin, rather than the usual spin, that commutes with Hamiltonian. Unexpectedly, these non-collinear magnets should also show collinear spin-split bands in k-space like collinear AMs. We therefore classify such non-collinear magnets as hyperspin altermagnets (HAMs), as opposed to the usual collinear AMs. Our theory elucidates the fundamental physics of AMs and HAMs and provides a framework for exploring the wide range of non-collinear magnets that may possess other kinds of conserved quantities.
Materials Science (cond-mat.mtrl-sci), Other Condensed Matter (cond-mat.other), Quantum Physics (quant-ph)
6 pages, 2 figures, 1 table
Phys. Rev. Lett. 137, 116704 (2026)
Irrationality Measure Controls Long-Wavelength Charge Fluctuations in Quasiperiodic Systems
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-09-11 20:00 EDT
Quasiperiodic order is characterized by irrational frequencies whose rational approximability known as irrationality measure defines distinct arithmetic classes. We establish that this arithmetic classification has direct physical consequences for long-wavelength charge fluctuations. In translation-covariant quasiperiodic systems, the infrared scaling of charge fluctuation is governed by the interplay between the irrationality exponent of irrational frequency and the large-harmonic decay of the hull charge profile: the latter determines the available charge weight, while the former controls how efficiently that weight is transferred to the infrared. Consequently, all algebraic irrational frequencies share the same arithmetic scaling, whereas exceptionally well-approximable transcendental frequencies can exhibit strongly enhanced infrared fluctuation scaling. We further prove that occupied states separated from the Fermi level by a gap stable throughout the hull contribute only an analytic infrared background, leaving the nontrivial scaling to near-Fermi states. Our results extend to general translation-covariant multi-frequency quasiperiodic systems.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Mathematical Physics (math-ph)
29 pages, 5 figures
Emergence of spin-orbit coupling among spin, atomic orbital, and Bloch dynamics in Janus double-transition-metal MXenes
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
We found a spin-orbit coupling to cause a simultaneous correlation among three degrees of freedom, the electronic spin, orbital, and Bloch dynamics in an investigation into the electronic structure of Janus double-transition-metal MXenes, Mo$ _2$ HfC$ _2$ OS and W$ _2$ HfC$ _2$ OS. In this paper, it is also revealed that the spin-orbit coupling causes a staggered spin configuration with a trigonal pattern around the $ \Gamma$ point near the insulating gap. We developed a reduced Hamiltonian describing the electronic states and show that the spin-orbit coupling cannot be equated with conventional forms for a single electron in solids, LS, Rashba, and Dresselhaus couplings, even in the approximation under the low-energy and small wave number condition. Because of the intrinsic shape of the conduction band, a trigonally alternating spin-momentum locking emerges with the spin axis perpendicular to the layer plane. The theoretical analysis shows that these Janus materials can provide a platform for exploring the spin-related phenomena due to the trigonal spin-momentum locking other than Rashba and Dresselhaus types.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
9 pages, 6 figures
Measuring chiral phonons
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Rahul Rao, Hanyu Zhu, Nicholas Kotov, Thuc T. Mai, Maria F. Muñoz, Dali Sun, Jun Liu, Wonjin Choi, Renee R. Frontiera, Angela R.H. Hight Walker
Chiral phonons are quantized vibrations where the atomic motion in a solid breaks improper rotation symmetries. In many cases, chiral phonons possess angular momenta and are therefore selective to circularly polarized light. Both fundamental and applied research efforts on chiral phonons have been gaining increasing attention owing to their importance in a variety of fields including spintronics, spin-selective chemical reactions, thermal transport, quantum information processing and biosensing, where the bi-directional spin-lattice coupling enabled by chiral phonons can be harnessed in new ways, and potentially lead to new functionalities. Thus far, the studies of chiral phonons across diverse materials platforms have evolved largely independently within these fields, but the experimental techniques are often interrelated. In this perspective, we present a detailed description, as well as advantages and disadvantages of the current approaches for experimentally measuring chiral phonons in chiral and achiral materials. We conclude with a discussion of new methods for measuring chiral phonons. Ultimately, this work seeks to offer an experimental guide for systematically investigating the properties of chiral phonons in various materials systems and applications.
Materials Science (cond-mat.mtrl-sci), Instrumentation and Detectors (physics.ins-det), Optics (physics.optics), Quantum Physics (quant-ph)
4 figures
A model of grain growth in UN integrating molecular dynamics, phase-field modeling, and uncertainty quantification
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Mohamed AbdulHameed, Fadel M. Nasr, Wen Jiang, Mahmoud Yaseen, Benjamin Beeler
Grain growth kinetics and grain-boundary (GB) properties in uranium mononitride (UN) are investigated through an integrated multiscale framework combining molecular dynamics (MD), phase-field modeling, and surrogate-assisted uncertainty quantification. MD simulations yield GB energies for 27 symmetric tilt boundaries from 0–2000K, which are consistent with available DFT values. The average GB energy is nearly temperature-independent below 1000K and increases at higher temperatures. A mechanistic pore-drag model applied to the only available grain growth dataset for actinide nitrides yields a mobility reduction factor of $ s \approx 0.93$ –$ 0.99$ , statistically indistinguishable from unity, confirming that pore drag is negligible under the experimental conditions. The intrinsic GB mobility is therefore extracted directly from the effective mobility, yielding $ M_0 = 2.05\times10^{-15}$ m$ ^4$ /(J$ \cdot$ s) and $ Q_M = 0.89$ ~eV. Phase-field simulations conducted from 1500–2000K confirm normal curvature-driven grain growth, with grain size distributions converging to the Hillert-like form. A surrogate-assisted global sensitivity analysis—combining principal component analysis, Gaussian process regression, and Sobol decomposition—reveals that the mobility prefactor $ M_0$ dominates output variance at all times, followed by the activation energy $ Q_M$ , while the GB energy $ \gamma$ contributes minimally. These results establish the first quantitative grain growth framework for UN and identify the reduction of uncertainty in $ M_0$ and $ Q_M$ as the highest-priority target for future experimental efforts.
Materials Science (cond-mat.mtrl-sci)
Silicon Solar Cell Design for >30% Efficiency via Singlet Fission
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Shona McNab, Phoebe Pearce, Pietro P. Altermatt, Jingnan Tong, Ruy Sebastian Bonilla, Timothy W. Schmidt, Murad J. Y. Tayebjee, Bram Hoex, Alison Ciesla, Michael P. Nielsen, Nicholas J. Ekins Daukes
Singlet fission (SF) materials convert high-energy photons into multiple charge carriers, providing a route to exceed the efficiency limits of single-junction silicon solar cells without many of the complexities of multi-junction tandem designs. Following the first demonstration of an SF-enhanced silicon solar cell in 2025, there is a need to understand how SF materials can be effectively integrated into high-efficiency industrial silicon devices and translated from proof of concept to a manufacturable technology. Using coupled optical and electrical simulations, we assess the efficiency potential of several industrially relevant silicon cell architectures combined with SF materials. Interdigitated back-contact (IBC) cells offer the greatest potential for improvement due to unrestricted front-surface access and can achieve efficiencies exceeding 33%. However, performance is highly sensitive to front-surface passivation quality. Appropriate silicon design, particularly controlled surface doping and fixed interfacial charge, can mitigate recombination losses and relax passivation requirements for ultra-thin exciton-transfer layers.
Materials Science (cond-mat.mtrl-sci)
U-Shaped Fermi-Level Dependence of Point-Defect Aggregation Enthalpy in Silicon
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Point defects govern the electronic and structural behavior of silicon, yet their configuration and energy depend on both the charge state and the Fermi level (EF). Using an unbiased global structure search with first-principles calculations, we screened more than 1,500 candidate structures, covering intrinsic defects and C, H, O, N, P, and B impurities in charge states from -2 to +2. The reaction enthalpy of defect aggregation depends on EF in a U shape, being strongest where the net charge transferred during the reaction vanishes and weaker toward both band edges. This U arises because complexes are more charge-neutral than their isolated constituents, so the net charge transfer changes sign across the gap. The point where this sign change occurs is set by the transition levels of the specific defects. For typical reactions, the driving force is tunable by 0.3-0.5 eV, which shifts the equilibrium complex concentration by five to eight orders of magnitude at room temperature. Our results make the Fermi level a practical lever for defect engineering in as-grown and irradiated silicon.
Materials Science (cond-mat.mtrl-sci)
A substrate booster for P-type 2D ferromagnetic semiconductor
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Hai Wang, Woye Pei, Ridong Cong, Xiaoyan Liu, Yuping Tian, Kenji Watanabe, Teng Yang, Takashi Taniguchi, Xiangru Kong, Weijiang Gong, Guowei Zhou, Xiaoxi Li, Hanwen Wang, Jixuan Wu, Jiezhi Chen, Xiaohong Xu, Tongyao Zhang
Spin transistors with its both charge and spin properties tuned via electrostatic gating are believed capable for widespread use, which however have proven challenging due to the extreme rareness of their physical base – magnetic semiconductors. The latter are limited within very few systems including diluted magnetic semiconductors (DMS) and two-dimensional ferromagnetic semiconductors (2D-FMS), and known to suffer from inadequate gate-tunability of their electric and/or magnetic properties. Here, we show a substrate engineering paradigm by interfacing few-layered Cr$ _{2}$ Ge$ _{2}$ Te$ {6}$ (FL-CGT) with an antiferromagnetic insulator CrOCl. Owing to the subtle interfacial charge transfer couplings, CGT can be drastically turned from an ambipolar semiconductor into a high performance P-type semiconductor. When cooled below the Curie temperature, the ON-OFF ratio in such substrate-boosted FMS field-effect transistor (FET) reaches 10$ ^{5}$ with its coercive field $ H{c}$ of magnetic hysteresis loop tunable by a factor of more than 200$ %$ , enabling {gate-assisted magnetic switching in the prototype semiconducting spin transistor architecture}. A crossover from critical power-law scaling to a dual power-law behaviour under heavy hole doping was further observed. Our findings {signify} an efficient interfacial charge transfer and electrically modulated magnetic anisotropy energy supported by calculations. This high performance P-type FMS-FET system suggests that active substrate-boosting paradigm might be a powerful path for the investigation of future gate-tunable spintronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
In-plane magnetic field control of anomalous Hall response enabled by magnetic anisotropy engineering
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
J. C. Rodriguez E., E. De Biasi, J. I. Facio, D. Salomoni, S. Auffret, R. C. Sousa, I. L. Prejbeanu, A. Bruchhausen, J. Curiale, L. Avilés-Félix
Engineering magnetic anisotropy provides a powerful route to control magnetization orientation and unlock emerging functionalities in opto-spintronic and current-driven devices. Beyond its role in magnetization reversal, the effective anisotropy can strongly influence the magnetotransport response, offering an additional degree of freedom to tune new device functionalities. In this work, we report a magnetotransport study of a ferrimagnetic [Tb/Co]$ _{\times 5}$ multilayer grown with a Tb thickness gradient, whose wedge-shaped tilts the uniaxial anisotropy axis slightly away from the film normal. Anomalous Hall resistivity measurements from 80 K to 300 K reveal a spin reorientation transition, while the angular dependence of the magnetotransport responses exposes the crucial role of the tilted anisotropy. A simplified macrospin model reproduces the full angular response across the transition and shows that the observed anomalous Hall effect when the in-plane magnetic field is applied originates from the tilt of the uniaxial anisotropy axis, which supplies a built-in symmetry-breaking mechanism, enabling in-plane field control over the out-of-plane anomalous Hall response, sign included. These findings establish tilted magnetic anisotropy as a promising route toward Hall effect-based sensor applications and highlight Tb/Co multilayers as a versatile platform for anisotropy-engineered spintronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Slow Dynamics and the Geometry of Jammed Packings
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-11 20:00 EDT
Saddle points in the energy landscape of granular packings dominate the discrete steepest descent dynamics and ultimately determine the path that an out of mechanical equilibrium packing will follow and the resulting stable minimum that it will find. The saddle points that ultimately determine the resulting minima tend to be low-index saddle points. For models with an analytic energy landscape, such as the $ p$ -spin model, the steepest descent minimization path is affected by higher-index saddle points, which pull the system towards saddle points of decreasing index before arriving at the minima. Here, we examine the steepest descent minimization path of granular packings and compare them to the $ p$ -spin model. We show that the granular packing steepest descent minimization paths act like their smooth energy landscape counterparts and get attracted by saddle points. The index versus time curves for all models follow a shifted, stretched exponential. We further show that the shape parameter for the granular packings is unchanged when the energy landscape is modified to become analytic (Gaussian potential in a harmonic well) or non-local (Mari-Krzakala-Kurchan). The $ p$ -spin, on the other hand, has a significantly larger shape parameter. The reason is not due to the dimensionality, packing fraction, nonanalyticity, or the locality of the Hamiltonian of the models. The exact reason for the discrepancy in the shape parameter is \st{still} an unsolved mystery.
Soft Condensed Matter (cond-mat.soft)
12 pages, 10 figures
Transdimensional quantum droplets in an optically trapped Bose mixture
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-09-11 20:00 EDT
Xiaoran Ye, Yi Zhang, Ziheng Zhou, Zhaoxin Liang
We study quantum droplets in a symmetric two-component Bose mixture with interspecies $ p$ -wave interactions and a two-dimensional transverse optical lattice. The lattice drives a crossover from an anisotropic three-dimensional gas to weakly coupled one-dimensional tubes. We calculate the ground-state energy and quantum depletion at the Gaussian level and derive their limiting forms. At $ y=g_{12}/g=-0.95$ , where the bare mean field is repulsive and no free-space droplet exists, the calculated bulk equation of state supports a self-bound minimum across the crossover: a negative lattice contribution at order $ n^{2}$ supplies the attraction in the three-dimensional regime, and attractive fluctuations do so in the quasi-one-dimensional regime, with the intermediate, transdimensional range described quantitatively by neither limit. The interspecies $ p$ -wave interaction modifies only the spin branch. In the parameter range studied, increasing its strength lowers the equilibrium density across the crossover, consistently with a weakening of the induced binding.
Quantum Gases (cond-mat.quant-gas)
15 pages, 5 figures
A Phase-Field Study of Desiccation Crack Pattern Maturation under Drying-Wetting Cycles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-11 20:00 EDT
Hiroki Fukushima, Satoshi Yukawa
The characteristic intersection angle of the desiccation crack relaxes from near \ang{90} toward \ang{120} under repeated drying–wetting cycles. However, the theoretical understanding of this relaxation is insufficient, especially the modeling of the drying–wetting cycles. Here we introduce a phase-field model of desiccation fracture, extending the model proposed in previous studies by adding crack healing and a scar effect left by past cracks. By repeating drying–wetting cycles in a finite element simulation, we find that the angle distribution develops a growing peak near \ang{120} as the cycle number increases, consistent with experiments. The standard deviation of the intersection angle from \ang{120} relaxes exponentially with a characteristic time of about 2.85 cycles. These results are consistent with experiments, except that the characteristic time is slightly smaller than the experimental value. Crack energy dominates the total energy and also relaxes exponentially with nearly the same characteristic cycle as the angle relaxation. This decay is driven mainly by a shortening of the effective crack length rather than a change in effective fracture toughness.
Soft Condensed Matter (cond-mat.soft), Pattern Formation and Solitons (nlin.PS)
38 pages, 10 figures
High-Performance Scaled P-Type SnOx Transistor by Atomic Layer Deposition with CFET Integration
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Ziheng Wang, Wen He, Chen Gu, Kai Jiang, Liankai Zheng, Jinxiu Zhao, Zhiyu Lin, Xiangjun Liu, Di Geng, Ling Li, Mengwei Si
The development of high-performance p-type oxide semiconductors is essential for realizing complementary logic for monolithic 3D integration, yet p-type oxide semiconductors still exhibit substantially inferior performance compared with their n-type counterparts. In this work, we demonstrate high-performance p-type SnOx transistors by atomic layer deposition (ALD), as back-end-of-line compatible devices for monolithic 3D integration. The SnOx transistors exhibit high field-effect mobility of 6.9 cm2/Vs, low subthreshold swing (SS) of 185 mV/dec, decent on/off ratio (ION/IOFF) of 1.8\ast104 and high bias stability. By scaling the channel length down to 80 nm, a high on-current of 38.7 mA/mm at VDS of -1 V is achieved. It is understood that precursor and reaction engineering to suppress Sn4+ component in SnOx film are the key for performance enhancement. Furthermore, a complementary field-effect transistor with ALD SnOx p-FET vertically stacking on ALD In2O3 n-FET is also demonstrated, achieving maximum voltage gain of 21 V/V at VDD of 4 V. These findings suggest ALD SnOx as a promising candidate for scaled high-performance BEOL p-type transistors.
Materials Science (cond-mat.mtrl-sci)
Fingerprints of Excitonic Collective Modes in the Two-Dimensional Electron Gas
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Jakob Wolff, Silvana Botti, Lucia Reining, Matteo Gatti
The two-dimensional homogeneous electron gas (2D HEG) is a prototype system of fundamental interest that can be realized experimentally over a wide range of densities. Here, we investigate its collective charge excitations at low densities, using time-dependent density functional theory. We demonstrate that, beyond traditional plasmons, new collective excitonic modes emerge for a Wigner-Seitz radius larger than $ r_{\mathrm s} \approx 1$ . These excitonic modes leave characteristic fingerprints in experimentally accessible quantities, namely, asymmetric peak structures in the loss function and very strong Friedel-like oscillations in the static linear density response that increase when the system approaches a regime of instability. Indeed, at low enough densities the collective modes cross the zero energy axis, indicating an instability of the paramagnetic 2D HEG towards the formation of a charge-density-wave phase with excitonic origin. These findings provide valuable insights for the experimental detection of excitonic collective modes in tunable 2D electron systems and contribute to the fundamental understanding of many-body effects in low-density electron gases.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
Interplay of spin-lattice and electronic coupling far above Neel ordering in 2D antiferromagnetic CrPS4 and its interface manifestation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Divya Jangra, Binoy Krishna De, Mukesh Kumar Dasoundhi, Sourav Chowdhury, Pragati Sharma, Kartick Biswas, Arup Basak, Dheeraj Kumar Gupta, Koushik chakraborty, Praveen Kumar Velpula, Pavan Nukala, U. Chandni, Arvind Kumar yogi, Mukul Gupta, Markus Hucker, Vasant G. Sathe
A short-range spin correlation driven, strongly intercoupled spin-phonon-electronic state far above TN (38K) is identified in the low dimensional van der Waals antiferromagnet CrPS4. Temperature-dependent Raman spectroscopy reveals spin-phonon coupling persisting up to T\ast120K, concomitant with local lattice distortion. The setting of vibronic progression in photoluminescence spectra suggests the strengthening of electron-phonon coupling around T\ast. Furthermore, both the electrical transport and optoelectronic response also change significantly at T\ast. The results indicate that spin-phonon coupling above TN in CrPS4 originates from local lattice distortion induced by short range magnetic correlations which in turn enhances the electron-phonon interaction. Furthermore, using a CrPS4/In2Se3 heterostructure, we demonstrate that the anomaly associated with the coupled degrees of freedom in CrPS4 also influences the adjacent In2Se3 layer. The lattice dynamics of In2Se3 is significantly modified across the magnetic anomaly of CrPS4, and the coupled dynamics is observed at T\ast. These interfacial manifestation opens up new possibilities for achieving correlated multifunctionalities in artificially designed heterostructure.
Materials Science (cond-mat.mtrl-sci)
Enhancing charge stability of Ge quantum well heterostructures via SiGe layer composition engineering
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Ding-Ming Huang, Jun-Hang Liu, Han Gao, Jie-Yin Zhang, Jian-Huan Wang, Fang-Ze Liu, Xin-Yu Zhou, Yi Luo, Bin-Xiao Fu, Xiao-Fei Liu, Ji-Yin Wang, Jian-Jun Zhang, H. Q. Xu
Composition modulation is a powerful technique for designing materials with tailored properties, fueling the development of advanced semiconductor devices. In this work, we have implemented this technique into Ge quantum well heterostructures, offering a promising avenue to address the critical challenge of charge stability in spin qubit devices. Harnessing the atomic-scale precision of molecular beam epitaxy, we have engineered the band structure of the SiGe top barrier via graded composition modulation, thereby reducing charge accumulation states at the SiGe-dielectric interface and strengthening the effective confinement to the hole gases in the Ge quantum wells. The enhanced charge stability of composition-modulated SiGe/Ge quantum well heterostructures is confirmed in Hall devices, featuring an enlarged stable gate voltage range. We have further fabricated quantum dot devices from the composition-modulated SiGe/Ge quantum well heterostructures and observed remarkably low charge noise with an averaged amplitude of $ 0.46,\mathrm{\mu eV}/\mathrm{\sqrt{Hz}}$ at $ 1,\mathrm{Hz}$ —the lowest reported value for Ge quantum wells grown on silicon. This exceptional charge stability of the quantum dots persists in the few-hole regime, with no observable voltage drift over $ \sim$ hours. With reduced charge noise and enhanced energy stability, composition-modulated SiGe/Ge heterostructures exhibit significant potential for applications in building high-performance quantum devices, including spin qubits with a long coherence time.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Quantum Physics (quant-ph)
Kinetics of ferritin crystal formation and melting in acoustically levitated droplets
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-11 20:00 EDT
Anita Girelli, Iason Andronis, Aigerim Karina, Sampad Bag, Lennart Bergström, Tomás Plivelic, Felix Roosen-Runge, Fivos Perakis
Understanding protein crystallization pathways is essential for controlling crystallization in structural biology, materials science, and pharmaceutical applications. Classical nucleation theory does not fully capture crystallization processes for several proteins, including ferritin. Here, we combine acoustic levitation with small- and wide-angle X-ray scattering (SAXS and WAXS) to monitor ferritin crystallization in evaporating aqueous polyethylene glycol (PEG) solutions. Acoustic levitation rapidly drives the droplets through a broad range of protein and polymer concentrations, enabling time-resolved measurements of crystallization during evaporation. The scattering data show that ferritin crystals form during evaporation and subsequently lose their crystalline order upon further dehydration. Varying the PEG molecular weight switches between distinct crystallization pathways: one dominated by attractive protein-protein interactions and another dominated by repulsive interactions and excluded-volume effects. Furthermore, we find that lower molecular weight PEG (1000 g/mol) suppresses the dehydration-induced loss of crystalline order observed for higher molecular weight PEG (6000 g/mol), providing a simple strategy for improving protein crystal stability.
Soft Condensed Matter (cond-mat.soft), Chemical Physics (physics.chem-ph)
Optically induced metallic state with persistent monoclinic symmetry in NdNiO$_3$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Christian Tzschaschel, Felix Utsch, Qi Song, Spencer Doyle, Grace A. Pan, Charles M. Brooks, Julia A. Mundy, Clemens von Korff Schmising, Stefan Eisebitt
Understanding whether electronic and structural order remain coupled under nonequilibrium conditions is a central challenge in correlated materials. Here, we simultaneously track metallicity and symmetry across the photoinduced insulator-to-metal transition in NdNiO$ _3$ using time-resolved optical reflectivity and symmetry-sensitive second-harmonic generation. We find that metallic reflectivity emerges at significantly lower excitation fluence than restoration of the orthorhombic high-temperature symmetry. As a result, optical excitation stabilizes a metastable state that combines the reflectivity of the metallic phase with the monoclinic symmetry of the insulating phase, revealing an optically induced monoclinic metal. Only at substantially higher fluences does the symmetry fully recover to that of the high-temperature phase. These results demonstrate a nonequilibrium decoupling of metallicity and structural symmetry and establish simultaneous multiprobe spectroscopy as a powerful approach for identifying emergent phases in correlated materials.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
12 pages, 4 figures
Interface-Controlled Phase Stability in Polymorphic HfO$_2$ Revealed by Machine-Learning Atomistic Simulations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Xudong Zhu, Junhong Li, Lixin He
HfO$ _2$ exhibits rich polymorphism, and competition among different phases underpins many of its functional properties. Yet bulk free-energy relations alone cannot explain phase selection at mixed-phase boundaries, where interface orientation and structural continuity constrain collective rearrangements. Here, using machine-learning atomistic simulations and a Hf-centered local phase classification scheme, we show that crystallographic interface matching redirects phase competition and accessible transformation pathways. The M(100)/T(100) interface remains pinned as an M/T mixture throughout 3 ns simulations from 300 to 1800 K. M/PO, M/AO, and PO/AO interfaces retain two-phase coexistence up to 900 K, whereas all T/PO interfaces become PO-dominant. At 1800 K, all non-M interfaces become T-dominant, while M-containing interfaces retain a monoclinic majority. Nudged elastic band calculations reveal lower-barrier routes through interface states. For M(100)$ \rightarrow$ T(100), the interface-mediated route in a long cell ($ \sim$ 12 nm) yields a barrier of 136.03 meV/f.u., 29.2 % lower than the direct route in a short cell ($ \sim$ 3 nm). This difference is associated with sequential phase-front motion absent from the short cell. These results identify phase boundaries as active participants in phase stability and transformation and establish interface orientation and crystallographic matching as variables for stabilizing metastable polymorphs and directing phase conversion in HfO$ _2$ .
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Universal sampling of spin systems across quenched disorder
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
Jing Liu, Yeyuan Wu, Ying Tang, Pan Zhang
Statistical physics extracts macroscopic laws by averaging over the many microscopic degrees of freedom of a system. Disordered systems demand a second and far harder average, one over the quenched randomness itself. The classic analytical routes, the replica and cavity methods, become uncontrolled outside mean-field or tree-like limits, and conventional numerical algorithms like parallel tempering require expensive, independent equilibration for every disorder realization. In this work, we introduce a universal neural variational framework that amortizes inference across the disorder ensemble, eliminating both the need for per-instance Markov chain equilibration and the cost of retraining instance-specific variational ansatzes. Built on an encoder-decoder Transformer architecture, after training once, it produces an explicit approximation to the Boltzmann distribution given previously unseen disorder realizations without further optimization. We validate this framework on 2D Edwards-Anderson models, and apply it to the random-bond Ising model, successfully capturing the Binder cumulant crossings near the Nishimori multicritical point. These results shift the object of variational inference from the single instance to the disorder ensemble, opening a route to frustrated many-body systems where instance-by-instance computation is prohibitive.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn)
7+9 pages, 4+7 figures
Information-Theoretic Characterization of Macroscopic Chaos Emerging from the Chemical Master Equation
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
Kenshin Matsumoto, Shin-ichi Sasa
Open chemical reaction networks exhibit stochastic concentration dynamics at finite system sizes, whereas their macroscopic limit is governed by deterministic rate equations that can display chaos. In this Letter, we show theoretically that a rate of information loss constructed from two-time mutual information recovers the Kolmogorov-Sinai entropy in the deterministic limit. We verify this result through numerical simulations of a Markov jump process for a three-species system involving seven reactions.
Statistical Mechanics (cond-mat.stat-mech)
7 pages, 4 figures
Correlation enhanced altermagnetism mediated by spin-lattice coupling in CrSb
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Charmi Bhalani, Banasree Sadhukhan
Altermagnets (AMs) exhibit momentum-dependent spin splitting without net magnetization, making them promising platforms for spintronic applications. While the symmetry and multipolar origins of nonrelativistic altermagnetic spin splitting (NRASS) are well established, the role of electronic correlations and spin-lattice coupling (SLC) in controlling NRASS remain unexplored. In particular, SLC provides a direct pathway for tuning altermagnetism through lattice degrees of freedom. Here we first investigate the role of electronic correlations on altermagnetic strength in NiAs-type material CrSb using density functional theory (DFT), DFT+$ U$ , and dynamical mean-field theory (DMFT). We find that increasing electronic correlations substantially enhance NRASS and drive the stabilization of an incommensurate spin-spiral (SS) state, while dynamical correlations further amplify the spin splitting through quasiparticle renormalization of the Cr-$ 3d$ states. We find that the NRASS remains 12.5% larger in DFT+DMFT than in DFT. By evaluating SLC in next step, we establish its direct connection to the evolution of NRASS and identify SLC as a microscopic descriptor between electronic correlation and enhanced altermagnetism in CrSb. Investigating it in another NiAs-type compound MnTe, we show that the SLC-NRASS correlation is generic across AMs and establish SLC as a microscopic descriptor of altermagnetic strength. Our results provide a unified framework for tuning altermagnetism through the interplay between the electronic correlations and lattice degrees of freedom.
Materials Science (cond-mat.mtrl-sci)
Orientational order on non-orientable domains
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
Gianmarco Spera, Axel Fotso Ndefo, Keaton J. Burns, Alexander Mietke
We study the statistical properties of passive and active many-body systems with orientational degrees of freedom on non-orientable domains. By rephrasing topological constraints as non-local symmetry relations on an orientable double-cover, we show that non-orientability eliminates global rotational soft modes without acting like an external field. In a passive XY model, this results in topological caging, where orientational fluctuations that exhibit conventional diffusive behavior on a torus saturate on a Klein bottle to a finite value that we compute exactly in the thermodynamic limit. In models of active self-propelled particles with orientational degrees of freedom, topological caging persists despite continuously changing interaction neighborhoods. In an active Ising spin model, non-orientability enforces the coexistence of ordered anti-parallel domains with vanishing global polar order, a state that is absent on orientable domains.
Statistical Mechanics (cond-mat.stat-mech), Soft Condensed Matter (cond-mat.soft)
15 pages, 5 figures
Disordered ground states in one-dimensional exactly solvable fluids
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
One-dimensional fluids of classical hard-core particles of diameter $ a$ , interacting in pairs via a soft repulsive (monotonically decreasing) potential of finite range $ \varphi(x)=\varepsilon \left[ (a’-x)/(a’-a)\right]^{1/\nu}$ $ (a\le x\le a’)$ with real positive parameters $ \varepsilon$ and $ \nu$ , are studied in an isothermal-isobaric ensemble. If $ a’\le 2a$ , the pairwise interactions are reduced to nearest-neighbour interactions, which allows for an exact solution of the thermal equilibrium. We focus on the $ T\to 0$ ground states, specifically on the equation of state for the mean distance between nearest neighbours $ l_0$ and the pair correlation function $ g_0(x)$ . If $ \varphi(x)$ is concave $ (\nu\ge 1)$ , there exists an ``incompressibility’’ pressure $ p_i=\varepsilon/(a’-a)$ such that the ground state is an equidistant chain of particles with spacing $ l_0=a’$ for $ 0<p<p_i$ and with spacing $ l_0=a$ for $ p>p_i$ . If $ \nu>1$ (strict concavity), the ground state at $ p=p_i$ is disordered with $ l_0=\left[ \nu a +(\nu-1)a’\right]/(2\nu-1)$ and $ g_0(x)$ being a superposition of weighted Dirac delta functions over discrete positions. If $ \nu=1$ (linear ramp), the ground state at $ p=p_i$ is disordered with $ l_0=(a+a’)/2$ and the continuous $ g_0(x)$ is a superposition of Heaviside step functions multiplied by polynomials in $ x$ . The isothermal susceptibility at $ T=0$ is nonzero for concave $ \varphi(x)$ ($ \nu\ge 1$ ) at $ p=p_i$ and, therefore, the corresponding disordered ground states are non-hyperuniform, i.e., they resemble disordered fluids at nonzero temperatures. It turns out that pair correlation functions of disordered ground states, which occur only at a single pressure $ p_i$ , extend their predictive power to thermodynamic states at nonzero temperatures over a wider range of pressures around $ p_i$ .
Statistical Mechanics (cond-mat.stat-mech)
20 pages, 5 figures
J. Phys. A: Math. Theor. 59, 365001 (2026)
Microwave-controlled interactions and stripe formation of static-field-shielded polar molecules
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-09-11 20:00 EDT
Tiziano Arnone Cardinale, Malte Schubert, Stephanie M. Reimann
We study polar molecules where short-range losses are suppressed by a shielding scheme involving a static electric field and an elliptically polarized microwave field. Using perturbation theory, we derive the effective interaction potential and validate it against coupled channel calculations. We identify a parameter regime where two-body losses are strongly suppressed and the extended mean-field description of dilute molecular Bose-Einstein condensates is justified. We calculate the collective excitations and show that intriguingly, supersolidity in quasi-two-dimensional confinement emerges as a stripe phase even at small values of microwave ellipticity.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
8 pages, 4 figures
Instabilities in self-consistent diagrammatic approaches and how to cure them
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Marcel Gievers, Herbert Eßl, Stefan Rohshap, Anna Kauch, Alessandro Toschi
While self-consistent diagrammatic approaches are widely used to compute the physical properties of correlated quantum materials, their applicability may get severely hindered precisely in the parameter regions, where the most exciting physics is observed. One of the major issues, referred to as “misleading convergence”, is the tendency of iterative schemes to converge to unphysical fixed points for intermediate-to-strong electronic interactions, regardless of numerical accuracy of the computation. Here, we explicitly verify that the origin of this problem in several established self-consistent many-electron approaches, defined in the general diagrammatic framework of the boson-exchange formalism, resides exclusively in the stability condition of the respective iteration schemes, and not in an intrinsic breakdown of their self-consistent diagrammatic description. This insight enables a simple and general remedy, as recently proposed in Phys. Rev. Lett. 137, 016502 (2026): The redefinition of the iterative procedure, by inverting the unstable eigendirections of the Jacobian associated to the fixed point of the self-consistent algorithm. We illustrate the successful outcome of this procedure by means of systematic calculations performed on testbed, exactly solvable, models. Our results demonstrate that the physical fixed point of the diagrammatic schemes we considered can be stabilized, de facto, across the entire parameter range, including the most challenging nonperturbative/strong-coupling regimes.
Strongly Correlated Electrons (cond-mat.str-el), Computational Physics (physics.comp-ph)
38 pages, 20 figures
Rare-History Transitions in Temporally Random Integrable Quantum Circuits
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
We study current fluctuations in a temporally random integrable quantum circuit. Commutativity reduces every drive history exactly to its layer composition, turning annealed fluctuations into a competition between current gain and the large-deviation cost of rare compositions. For each fixed composition, homogeneous thermodynamic Bethe ansatz dressing supplemented by ballistic fluctuation theory yields the conditional current statistics. Their annealed large-deviation contraction predicts a first-order switch between two dominant history classes, terminating on a line of regular cusp endpoints. Finite-time analysis shows how the switch is rounded. Thus temporal randomness can act as an emergent order-parameter-like coordinate in trajectory space.
Statistical Mechanics (cond-mat.stat-mech), Exactly Solvable and Integrable Systems (nlin.SI), Quantum Physics (quant-ph)
5 pages, 2 figures. Supplemental Material will be submitted separately. This is an initial draft, and comments are welcome
Anisotropy of Ultrafast Strain in $V_2O_3$ Thin Films: Out-of-Equilibrium Phase Transitions under Interfacial Clamping
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
J. Guzman-Brambila, R. Mandal, D. Lea, E. Trzop, M. Servol, J. C. Ekström, F. Pawula, J. Tranchant, L. Cario, M. Lorenc, E. Janod, C. Mariette
Ultrafast photoinduced insulator-to-metal transitions in correlated materials are often mediated by lattice distortions, yet the role of interfacial lattice constraints in shaping nonequilibrium pathways remains largely unexplored. We use azimuth-resolved time-resolved X-ray diffraction to track orientation-dependent strain dynamics in granular V$ _2$ O$ _3$ thin films on c-cut sapphire, where thermal-expansion mismatch imposes anisotropic interfacial strain. Across the thermal transition, the azimuthal profile of the (110)$ _H$ strain inverts curvature, providing direct evidence of partial clamping of the hexagonal basal-plane lattice (a$ _H$ ,b$ _H$ ). After photoexcitation of the antiferromagnetic insulating phase, the structural response remains clamp-limited: weakly constrained grain families reach the full basal-plane contraction characteristic of the metallic-like state, whereas strongly constrained families exhibit a strongly reduced distortion. Fluence-dependent measurements further disentangle transformed fraction from clamping-limited lattice distortion. Our results show that interfacial clamping acts as a static selector for ultrafast phase switching and provide a general route to quantify anisotropic strain dynamics in heterostructures.
Materials Science (cond-mat.mtrl-sci)
Vacancy Order and Physical Properties of a Ternary Compound Fe0.68Pd0.80Te with an α-Fe1+xTe-Type Structure
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Bingxian Shi, Manyu Wang, Chenglin Shang, Yanyan Geng, Yangyang Fan, Xiaoxiao Pei, Li Huang, Daye Xu, Juanjuan Liu, Jinchen Wang, Hongxia Zhang, Hongliang Wang, Lijie Hao, Rui Xu, Zhongyi Lu, Zhihai Cheng, Peng Cheng
We report the identification and characterization of a new compound Fe0.68Pd0.80Te with an {\alpha}-Fe1+xTe prototype structure. Different from the Fe-square net and minor occupancy of interstitial Fe-sites in Fe1+xTe, Fe0.68Pd0.80Te is featured by a Pdsquare net and near 68% occupancy of the corresponding interstitial Fe-sites. Furthermore, noncontact atomic force microscopy and X-ray diffraction provide evidence for the existence of a 3\ast3\ast3 Pd-vacancy order in this layered material. A spin-glass ground state below Tg 40 K is identified via magnetic characterization. Electrical transport measurements show that Fe0.68Pd0.80Te is a semiconductor with a very small band gap below 10 meV. It has weak negative magnetoresistance and holelike charge carriers below room temperature. Our results demonstrate its potentials for further exploring various quantum phenomena.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
8 pages, 4 figures
Inorg. Chem. 2026, 65, 20285-20292
Bottom-up Synthesis of Metastable 2D Hexagonal Copper(I) Iodide on Monolayer and within Bilayer Graphene
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
David Kaiser, Guobin Jia, Janis Köster, Sadegh Ghaderzadeh, Christian E. Halbig, Siegfried Eigler, Andrey Turchanin, Benjamin Dietzek-Ivanšić, Arkady V. Krasheninnikov, Jonathan Plentz, Elena Besley, Ute Kaiser
Copper(I) iodide (CuI) is a wide-bandgap semiconductor crystallizing in the 3D $ \gamma$ -phase under ambient conditions; its layered van der Waals bulk phase $ \beta$ -CuI is stable only between 643 and 673 K. The two-dimensional (2D) h-CuI form has been obtained via liquid-phase exfoliation of mechanochemically prepared precursors and via encapsulation between graphene sheets, whereas bottom-up growth of 2D h-CuI on open surfaces has not yet been demonstrated. Here, we report a vapor-phase synthesis of h-CuI directly on low-defect, large-area monolayer and within bilayer reduced oxo-graphene (r-oxo-G) at low temperatures. Using a copper TEM grid as the solid-state precursor for copper, HI-vapor exposure at 40 $ °$ C initiates nucleation, while annealing at 180 $ °$ C promotes the growth of extended h-CuI domains. Aberration-corrected HRTEM resolves the atomic structure, local twist angles, and lattice anisotropy of the CuI/r-oxo-G nanohybrid, while STEM-EDX yields a Cu:I ratio consistent with 1:1. First-principles calculations show that van der Waals adhesion to graphene stabilizes the supported hexagonal layer. Under the presented low-temperature precursor conditions, pathways for nucleation of the $ \gamma$ -phase are not available, allowing the hexagonal phase to form selectively at the graphene interface. Ab initio molecular dynamics simulations show that the heterostructure retains its hexagonal lattice order at 600 K, including on an open monolayer graphene support. The lateral extent of the growth is limited mainly by remaining interfacial adsorbates. These results establish a route to metastable 2D h-CuI on a chemically inert graphene template, which may be useful for wide-bandgap electronic and optoelectronic devices.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Applied Physics (physics.app-ph)
26 pages, 6 figures, Includes Supporting Information with 5 figures and 7 tables
A Community-Developed Domain Ontology for Magnetic Materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Wilfried Hortschitz, Santa Pile, Claas Fillies, Harald Oezelt, Alexander Kovacs, Hans Fangohr, Samuel J. R. Holt, Martin Lang, Andrea Petrocchi, Swapneel Pathak, Michael P. Adams, Jonas Winkler, Thomas G. Woodcock, William Rigaut, Pierre Le Berre, Nora M. Dempsey, Alena Vishina, M. Nur Hasan, Georgia A. Marchant, Heike C. Herper, Thomas Schrefl
Magnetic materials play a crucial role in energy-related technologies, mobility, and sensing, but their complex multiscale behaviour and the coexistence of multiple unit systems pose persistent challenges for data exchange and interpretation. This paper presents a domain ontology for magnetic materials, developed within the European Union funded Magnetic Multiscale Modelling Suite (MaMMoS) project and aligned with the Elementary Multiperspective Material Ontology (EMMO). The ontology formalises intrinsic, hysteretic, and microstructural properties across multiple length scales and supports semantic interoperability between simulation tools, databases, and experimental workflows. One key feature of the ontology is its code-based and human-readable structure, enabled through the EMMOntoPy framework, which allows for direct manipulation and versioning without relying on opaque .owl or .ttl files. This facilitates collaborative development and improves transparency. The ontology supports FAIR (Findable, Accessible, Interoperable, Reusable) principles and is openly available for extension by the community. The aim of the MaMMoS project is to foster reproducibility, improve traceability, and promote the adoption of ontology in the magnetism domain. The ontology that has been developed already serves as the foundation for multiple software tools that handle all kinds of magnetic material data.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Submitted to Applied Ontology (SAGE)
Topological band structure of excitons in octochlore KTb${3}$F${10}$: an analog of the Luttinger Semimetal
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Olivier Demortier, Françoise Damay, Paul McClarty, Stéphane Raymond, Jacques Ollivier, Sylvain Petit
Understanding the symmetry and topology of band structures in crystalline solids has been among the defining themes of a generation of condensed matter physicists, with implications across many different platforms including electronic bands, photonic crystals, phonons and magnetic excitations. In the latter systems, there is usually magnetic long-range order and time reversal symmetry breaking. Here we further enrich the possible band structures available to magnetic systems by examining dispersive crystal field excitations above a ground state that is a simple product of singlets. In these systems, there is an interplay of magnetic interactions and band topology with both crystal and time reversal symmetries. Using high-resolution neutron spectroscopy we reveal the dispersion relations of bosonic excitons in KTb$ _{3}$ F$ _{10}$ , an experimental realization of the octochlore lattice. We show that there are pinch point features in the scattering intensity. The dominant coupling in this system is the long-range magnetostatic dipolar interaction, whose singularity at the zone center is passed onto the scattering intensity. However, the pinch points survive when the range of the dipoles is truncated to finite shell number in the form of a three-band quadratic band touching protected by cubic symmetry. This model, which is related to the Luttinger semi-metal, provides a general long wavelength model for the emergence of pinch point scattering intensity encompassing also the true long-range dipolar model.
Strongly Correlated Electrons (cond-mat.str-el)
4 figures
Work as a function of protocol duration for the efficient erasure of an underdamped memory: isothermal to adiabatic transition
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-09-11 20:00 EDT
Nicolas Barros, Stephen Whitelam, Sergio Ciliberto, Ludovic Bellon
We use evolutionary reinforcement learning to determine efficient time-dependent erasure protocols for an underdamped cantilever moving in a double-well potential, an experimental realization of a 1-bit memory. We investigate how the mean work $ \langle W \rangle $ needed to erase a bit scales as a function of the protocol duration $ \tau$ . We find two regimes, depending on how $ \tau$ compares to the relaxation time of the system $ t_r$ . For $ \tau \gg t_r$ , the quasistatic isothermal regime, we recover Landauer’s bound plus an overhead that scales as $ 1/\tau$ , similar to the overdamped case. By contrast, for $ \tau<t_r$ erasure becomes adiabatic and $ \langle W \rangle$ grows more slowly than in the isothermal case. This growth is bounded from below as $ 1/\tau$ , which we derive using a gedanken optimal protocol. Finally, comparison with overdamped erasure shows that learned protocols can outperform protocols that are optimal subject to equilibrium boundary conditions.
Statistical Mechanics (cond-mat.stat-mech)
Néel-Vector-Dependent Altermagnetic Spin Splitting in the One-Dimensional Limit
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Altermagnetism is normally identified by nonrelativistic spin-split bands in a compensated collinear magnet. Under one-dimensional confinement, however, this diagnostic can disappear: a boundary-compatible sublattice-exchange operation may leave the only Bloch momentum unchanged, forcing the nonrelativistic spin-up and spin-down spectra to coincide. We show that nonrelativistic spin degeneracy can coexist with relativistic spin splitting in a compensated one-dimensional magnet. In a Lieb-based construction, confinement along the diagonal cancels the projected $ d$ -wave spin splitting while preserving the real-space sublattice-exchange motif. Spin-orbit coupling (SOC) then locks spin to the lattice, so the Néel-vector orientation selects a magnetic line group that can reveal spin-split bands. Using fully compensated $ [110]$ Ta$ _2$ TeSeO nanoribbons as a prototype, we find spin-degenerate nonrelativistic bands and sizable SOC splitting in the inherited easy-axis domain, $ \mathbf N\parallel[100]$ or $ [010]$ . For sufficiently wide ribbons that retain the parent easy-axis order, this splitting is an equilibrium property. The easy-axis ribbon also supports a right-moving-mode spin polarization of about $ 35%$ at finite ideal conductance. Our results establish one-dimensional fully compensated altermagnetic functionality hidden inside apparently conventional antiferromagnetic bands.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 4 figures
Skyrmion nucleus resolves the Landauer paradox
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Jiyuan Yang, Denan Li, Shi Liu
Ferroelectric switching is among the most fundamental and widely studied symmetry-breaking processes in physics. However, the Landauer paradox asserts that an ideal single-domain ferroelectric should be kinetically unswitchable, because a three-dimensional reversed nucleus would carry a prohibitive depolarization penalty, leading to unphysically large coercive field (the electric field required to switch the polarization). Here we show that this long-standing paradox is resolved by topology. In defect-free PbTiO3, large-scale molecular dynamics simulations reveal that the intrinsic critical nucleus is a three-dimensional polar skyrmion. Its continuous polarization rotation and Néel-type boundary walls self-compensate bound charge, suppressing the depolarization energy by orders of magnitude and bringing the predicted coercive field into agreement with experiment. This topological nucleus further overturns the 60-year-old Janovec-Kay-Dunn law. We derive an analytical thickness-dependent coercive-field law governed by field-induced softening of the parent ferroelectric state and controlled by a single material descriptor. This framework captures diverse experimental trends across ferroelectric families and recasts the Kay-Dunn exponent of -2/3 as an effective finite-window behavior. These results establish polar topology as an organizing principle for intrinsic switching and suggest that hidden topological transition states may broadly shape nonequilibrium phase transformations traditionally understood as Landau-type symmetry breaking.
Materials Science (cond-mat.mtrl-sci)
Finite-time effects in periodically kicked systems
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-09-11 20:00 EDT
F. Revuelta, R. Chacón, F. Borondo
In this work, we study finite-time effects in ultracold atomic systems by considering time-dependent modulations with variable waveforms and durations. These two characteristics can be controlled by adjusting only a single parameter. For arbitrarily short pulses, our model recovers the paradigmatic kicked rotor while maintaining the impulse transmitted per period and unit amplitude constant. Furthermore, we demonstrate that finite-time effects have a profound impact on dynamical localization, a result that cannot be captured by the {\delta}-kicked-rotor model. Through a detailed analysis of the effects of different modulation amplitudes, periods, and waveforms, we identify the conditions for which dynamical localization is significantly enhanced. We show that the strength of dynamical localization increases sharply as the system approaches the {\delta}-kicked-rotor limiting case. Moreover, we establish the existence of an optimal value of the period that maximizes dynamical localization for given values of the amplitude and shape parameter.
Quantum Gases (cond-mat.quant-gas), Chaotic Dynamics (nlin.CD), Quantum Physics (quant-ph)
8 pages, 5 figures
Effect of Stress and Surface Roughness on Electrodeposition in All-Solid-State Batteries: A Computational Investigation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Kaniza Islam, Ayush Morchhale, Jung-Hyun Kim, Yanzhou Ji, Noriko Katsube
All-solid-state batteries (ASSBs) promise high energy density and enhanced safety, but their development is hindered by instability and incompatibility at solid-solid interfaces. In Li-metal ASSBs, lithium penetration occurs despite stiff ceramic electrolytes via grain boundaries, often initiated by minor Li/SE interfacial irregularities. Here we introduce a two-dimensional continuum model with electro-chemo-mechanical coupling to investigate interfacial current distribution in Li ASSBs with surface-roughened argyrodite electrolyte under stack pressures and applied current density. Our theoretical analysis and simulation studies highlight the critical role of mechanical stress in interfacial current distribution. We find that prominent stress variations around elongated surface protrusions are the key to nonuniform Li deposition, without which Li deposition becomes uniform even on a rough surface. Moreover, our parametric study elucidates that stress effects dominate the overpotential and current distribution under low interfacial current density to exchange current density ratios, otherwise the high interfacial resistance due to surface-roughness-induced interfacial area becomes dominant. With these insights, we also discuss the potential of engineering artificial interlayers to modulate interfacial current distributions, offering guidance for improving the long-term performance and reliability of ASSBs.
Materials Science (cond-mat.mtrl-sci)
Robust Spin-1 Haldane Topology under Itinerant Doping
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
We study itinerant hole doping of the spin-$ 1$ Haldane symmetry-protected topological (SPT) phase in two $ t$ –$ J$ chains coupled by ferromagnetic (FM) Hund exchange. Density-matrix renormalization group calculations show that string order, a finite spin gap, and the Haldane entanglement structure coexist over a broad doping range. Combined with entanglement-entropy scaling consistent with a single gapless charge mode, these results support a metallic doped Haldane SPT with a $ C1S0$ low-energy description. At low doping, short-range charge correlations reduce the density of spin-$ 1/2$ defect rungs, whereas at larger doping their positions become nearly uncorrelated while their spins are collectively incorporated into the correlated spin sector. The doped Haldane SPT terminates in a fully spin-polarized FM phase, which forms a reentrant pocket at high doping in the global phase diagram. Dilute-limit analyses trace the two FM boundaries to spin–charge factorization at weak Hund coupling and to rung-triplet binding with reduced pair mobility at strong Hund coupling. Our results show how mobile carriers reorganize the Haldane spin structure while preserving its characteristic signatures.
Strongly Correlated Electrons (cond-mat.str-el)
6 pages, 4 figures, Supplemental Material
Phase-Controlled Majorana Zero Modes in Altermagnetic Topological-Insulator Josephson Junctions
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Hao Dong, Xun-Jiang Luo, Xiao-Hong Pan, Xin Liu
We exploit facet-dependent Andreev phase shifts to control topological superconductivity with a phase bias in a three-dimensional altermagnetic topological-insulator Josephson junction. In the weak link between two conventional s-wave superconductors, the d-wave altermagnetic order produces facet-dependent momentum shifts of the surface Dirac cones. The resulting net momentum of the states involved in Andreev reflection generates additional propagation phases that differ between facets. Consequently, the facet-resolved Andreev spectra exhibit gap closings at distinct phase biases, giving rise to topological superconducting regimes that host Majorana zero modes(MZMs). We further show that tuning the phase bias controls the spatial localization of these modes. The associated topological superconducting transitions are only weakly affected by moderate variations in the chemical potential, obviating the need for fine-tuning to the Dirac point. Our results establish a platform for realizing and spatially controlling MZMs by tuning the superconducting phase bias in altermagnetic topological-insulator Josephson junctions.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
11 pages, 4 figures
High-throughput thermodynamic screening of oxide-scale adhesion across the CoCrFeMnNiAl high-entropy alloys
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
One significant benefit of reactive element (RE) additions is the colossal improvement in oxide-scale retention during high-temperature oxidation. Selecting optimal RE dopants in high-entropy alloys remains empirical because the relevant thermodynamic landscape is inaccessible to first-principles at the required compositional resolution. Here we apply the macroscopic atom model, coupled with McLean isotherm and Guttmann models, to screen adhesion across nine CoCrFeMnNiAl sub-families at \ce{Cr2O3} and \ce{Al2O3} interfaces, ranking five REs (Hf, Y, Zr, La, Ti) for segregation, adhesion enhancement, and sulfur displacement. The screening reveals an oxide-dependent ranking inversion, with Hf dominating at \ce{Cr2O3} and La dominating at \ce{Al2O3}, driven by the interplay between RE–O and RE–matrix interaction enthalpies. Mn-containing alloys exhibit intrinsic sulfur resistance, consistent with their experimentally observed oxidation characteristics. A sulfur immunity phase diagram identifies compositions with Al+Mn$ \gtrsim$ ~25at% as thermodynamically immune to S-induced adhesion loss. All crossover concentrations collapse onto a universal exponential governed by the segregation enthalpy difference, providing a transferable design rule. Inverse design identifies \ce{Co16Cr16Fe16Ni16Al35} as the optimal S-immune composition with $ W_\text{sep} = 5.95$ ~J/m$ ^2$ without RE doping.
Materials Science (cond-mat.mtrl-sci)
Competition between vacancy creation and filling in defect-engineering of hBN
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Shrirang Chokappa, Manuel Laängle, Barbara Maria Mayer, Vladimir Zoba\vc, Jacob Madsen, Diana Propst, David Lamprecht, Philipp Irschik, Arixin Bo, Clara Kofler, Vinzent Hana, Fabian Kraft, Clemens Mangler, Lado Filipovic, Toma Susi, Jani Kotakoski
Hexagonal boron nitride (hBN) has recently become the focus of intense research as a material that can host quantum emitters. It is known that such emission is related to point defects, but in order to conclusively correlate specific defects to their spectra, having control over the defect creation mechanism is required. Here, we prepare freestanding, monolayer hBN samples and irradiate them with ultra-low-energy (150 eV) Ar+ ions. The samples are characterized before and after irradiation via scanning transmission electron microscopy to assess the defect density and distribution. Contrary to what analytical potential molecular dynamics simulations have predicted, we predominantly observe boron single vacancies after ion irradiation, followed by double vacancies at half the count. Moreover, we also observe that vacancy filling with Si and C impurity atoms plays a more significant role in the created defects than previously assumed, potentially posing a problem for selective creation of quantum emitters in hBN.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
22 pages, 13 figures (including the supplement)
Certified reduced-basis emulation of conformal field theories on the fuzzy sphere
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Fuzzy-sphere regularization gives numerical access to three-dimensional conformal field theories (CFTs), but locating one requires testing for criticality across the parameter space of microscopic couplings. We reduce the search cost by about two orders of magnitude, combining an exact diagonalization based on states having definite total angular momentum with a certified reduced-basis emulator that reconstructs energies, observables and their derivatives continuously across the couplings from a handful of exact solutions per system size. The combination reproduces the published ground-state-energy analysis of the fuzzy-sphere Ising model and the published conformal data of a three-flavor fuzzy-sphere realization of the O(2) Wilson–Fisher CFT, including quantities defined by parameter derivatives. Applied to the O(2) model with no CFT input, the ground-state-energy criterion locates the critical coupling to within half a percent of a density matrix renormalization group value obtained on systems more than twice the size, and maps the critical line of the model across the coupling plane. Ground-state criteria locate the critical line robustly, but the point they select along it is weakly determined, and the computed dimensions come closest to the bootstrap elsewhere along the line.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th)
12 pages, 7 figures
Acoustic Wave-Function Imaging of Sublattice Physics in a Kagome Lattice
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
L. Müller, N. Endres, B. Geldiyev, S. Widmann, K. Burkard, M. Ünzelmann, F. Reinert
The canonical kagome band structure hosts a Dirac cone, saddle-point van Hove singularities (vHS), and a flat band. Characteristically, these features exhibit distinct sublattice localization within the three-site basis of the kagome lattice. However, experimental proof of this sublattice character is challenging and requires direct access to both the real-space wave function and its associated momentum-space texture. Here, we implement an acoustic kagome lattice on the cm scale and measure the full excitation spectrum, thereby imaging the wave function at each lattice site, including both amplitude and phase. This enables investigation of the momentum-dependent sublattice texture across the complete band structure, particularly at the flat band and at the mixed- and pure-sublattice van Hove singularities. Our results are in excellent agreement with minimal tight-binding model calculations and constitutes the first direct experimental observation of the sublattice-resolved band structure in a kagome lattice.
Strongly Correlated Electrons (cond-mat.str-el)
Bridging steady-state and time-domain descriptions of molecular electron transport
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Thibaut Lacroix, Namgee Cho, Clemens Vittmann, James Lim, Susana F. Huelga, Martin B. Plenio
Electron transmission from an input electrode, through a molecular system, to an output electrode has been widely studied using the steady-state non-equilibrium Green’s function (NEGF) method. Recently, the wave packet method, which provides access to the transient dynamics of electrons as well as internal molecular degrees of freedom, has been employed to investigate enantiospecific electron transport through chiral molecules. In this work, we derive the quantitative relation between the transmission of a finite-size wave packet and the energy-resolved NEGF transmission, showing that the former corresponds to a spectral average of the latter weighted by the wave packet energy distribution. Exploiting this correspondence, we construct non-Gaussian auxiliary wave packets whose spectral weight encodes the Landauer energy-window, allowing current-voltage characteristics to be obtained directly from time propagation. We further show that the correspondence extends to spin-resolved transport in a spin-phonon model of chirality-induced spin selectivity.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
10 pages, 5 figures
Out-of-equilibrium relaxation dynamics of the superconducting order parameter in CsV$_3$Sb$_5$
New Submission | Superconductivity (cond-mat.supr-con) | 2026-09-11 20:00 EDT
Avi Shragai, Alexander Won, Jonathan M. DeStefano, Andrea Capa Salinas, Ganesh Pokharel, Stephen D. Wilson, B. J. Ramshaw
The application of a time-varying strain field drives a superconducting order parameter out of equilibrium. How the order parameter relaxes back to equilibrium depends both on the structure of the superconducting gap and on the nature of quasiparticle scattering. We report the discovery of an ultrasonic attenuation peak inside the superconducting state of the kagome superconductor CsV$ _3$ Sb$ 5$ . This peak is the natural consequence of the order parameter relaxation time matching the ultrasonic drive frequency near $ T{\rm c}$ . From the measured frequency dependence of the peak, we extract a microscopic scattering time of $ \tau_N = 25$ ps. This timescale is two orders of magnitude longer than the elastic scattering time as determined by resistivity measurements, but is comparable to the inelastic scattering time determined by thermal transport. Within the conventional framework of order-parameter relaxation, this implies that elastic scattering is ineffective at relaxing the superconducting condensate, consistent with a sign-preserving $ s$ -wave state obeying Anderson’s theorem.
Superconductivity (cond-mat.supr-con)
Impact waves in soft bilayer tissues
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-09-11 20:00 EDT
Zhenwei Liu, Yang Liu, Michel Destrade, Yue-Sheng Wang
In this study, we investigate impact-wave propagation in a pre-stressed compressible hyperelastic bilayer resting on a frictionless rigid substrate within the framework of nonlinear elasticity. Semi-analytical solutions for the transient displacement fields induced by localized surface impulses are derived using the Fourier-Laplace transform, and their long-time asymptotic behavior is obtained through the method of stationary phase. Finite element simulations are further performed to validate the theoretical predictions. The results establish a direct connection between characteristic features of the transient displacement fields and the group velocities of the guided-wave modes, revealing how dispersive propagation and modal contributions shape the observed waveforms. Three representative bilayer models corresponding to human articular cartilage, gingiva, and skin are then considered to examine the effects of variations in layer stiffness and thickness. The results show that structural and material variations can substantially modify the spatial distribution, arrival positions, and characteristic velocities of impact waves. In particular, higher-order modes can make significant contributions to the displacement response in certain parameter regimes, such that the dominant features of the wavefield cannot always be characterized by the fundamental mode alone. These findings demonstrate that transient-wave measurements contain mechanical information beyond that captured by a single characteristic surface-wave velocity and provide a theoretical basis for interpreting transient wavefields in multilayered soft materials and for future non-invasive mechanical characterization.
Soft Condensed Matter (cond-mat.soft)
38 pages, 14 figures
Interplay of Kekulé order, flat bands and electron-phonon coupling in graphene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
The Kekulé order in graphene is known to give rise to extended flat bands near the van Hove singularity (VHS) and enhanced electron-phonon coupling. However, the microscopic mechanism underlying the coexistence of these effects remains unclear. Here, it is shown that they jointly emerge as a consequence of the lattice distortion manifested through the differentiation of carbon bonds and associated electronic hoppings. In this picture, the conduction band around the $ M$ point decreases almost linearly in width with increasing Kekulé order, while the VHS and dimensionless electron-phonon coupling exhibit approximately quadratic upward responses. The resulting enhancement of the electron-phonon coupling is governed predominantly by the increasing density of states at the VHS, with the effective deformation potential remaining weakly affected by the distortion. As such, the obtained results are consistent with previous related theoretical and experimental studies, while also pointing toward a potential shallowing of the conduction band under the characteristic $ 1/4$ filling and an increasing relevance of nonadiabatic electron-phonon effects beyond the conventional Migdal approximation. Altogether, these findings highlight the potential of controlled Kekulé ordering for engineering emergent correlated quantum phases in graphene.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
6 pages, 4 figures
Hilbert-space selected switch of helical edges in an artificial quantum Hall insulator
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Naijie Ren, Zhiren Xiong, Kaining Yang, Yanran Shi, Hanwen Wang, Kenji Watanabe, Takashi Taniguchi, Neng Wan, Xiaojun Jia, Jianpeng Liu, Zheng Vitto Han, Yaning Wang
Quantum Hall effects (QHE) host one-dimensional topologically-protected edge channels, which can serve as an essential ingredient in exotic quantum electronic systems. Yet the manual reconstruction of Landau-level topology, by electrostatic confinement or symmetry breaking, remains experimentally challenging. Here, we show that interfacial charge transfer in between CrOCl and large-angle twisted bilayer graphene offsets the two otherwise decoupled Dirac Landau-level ladders in each graphene layer, creating a new sequence of composite filling configurations. At charge neutrality, the composited $ (+2,-2)$ state involves only the zeroth Landau levels and becomes fully insulating, with longitudinal resistance reaching the G$ \Omega$ regime. By contrast, higher composite zero-filling quantum Hall states, including $ (+6,-6)$ and $ (+10,-10)$ , retain counter-propagating helical edge channels and exhibit pronounced non-local transport, reaching up to $ 50%$ of the local response. We attribute such switching-behavior to the Landau-spinor Hilbert space – as the filling is reduced from $ (+6,-6)$ to $ (+2,-2)$ , the orthogonal $ N=\pm1$ orbital components are removed, eliminating the edge-compatible channel and gapping both bulk and boundary transport. The interaction nature of the observed gapped sates was further examined both experimentally and theoretically. Our results suggest that charge transfer provides a direct route to engineer artificial quantum Hall insulators, opening possibilities for wavefunction-selective control of helical edge modes.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
12 pages, 4 figures
Unraveling the Kagome Antiferromagnetic $3J$ Model and Its Materials: An Integrated Approach
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Xin Lu, Andreas Raikos, Menghan Song, Zezong Li, Lankun Han, Shiliang Li, Sylvain Capponi, Zi Yang Meng, Chengkang Zhou
We investigate the ground-state and finite-temperature properties of the kagome antiferromagnetic Heisenberg model with three inequivalent couplings, dubbed the 3J model, which is designed for the candidate Dirac quantum spin liquid (QSL) material YCu$ _3$ (OH)$ _6$ Br$ _2$ [Br$ _{1-x}$ (OH)$ x$ ] (see, e.g., Zeng et al., 2024). Employing large-scale density-matrix renormalization group (DMRG) supplemented by neural quantum states (NQS) simulations, we identify an intermediate QSL phase between two magnetically ordered phases. We also find that this QSL is separated from the kagome spin liquid ground state at the isotropic limit. To establish a direct comparison with experiments, we compute the specific heat of the model by means of advanced exponential (XTRG) and tangent-space (tanTRG) thermal tensor-network methods. In the magnetically ordered phase, the specific heat over temperature exhibits a shoulder at a temperature that is a fraction of the coupling strength $ J{hex}$ , which disappears in the QSL phase. These universal behaviors are consistent with the experimentally observed specific heat in 3J materials for both ordered and QSL candidate samples. Our work thus connects microscopic models with experimentally measurable signatures, exemplifying an integrated approach (see Meng et al., 2026) to understanding QSL phenomena in frustrated quantum magnets, with 3J materials serving as a representative case and providing a foundation for future studies.
Strongly Correlated Electrons (cond-mat.str-el)
9+7 pages, 5+7 figures
Device Engineering and Performance Optimization of Cu2NiGeS4 Thin-Film Solar Cells with In2S3/MoTe2 Charge-Selective Layers: A Computational Study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Md Tashfiq Bin Kashem, Hasib Md Abid Bin Farid
The pursuit of efficient and sustainable thin-film photovoltaics increasingly demands absorber materials that combine strong optical absorption with earth-abundant and environmentally benign constituents. Cu2NiGeS4 (CNGS) has emerged as a promising quaternary chalcogenide absorber owing to its favorable optoelectronic properties and high absorption coefficient, yet its photovoltaic potential remains comparatively underexplored, particularly in conjunction with optimized charge-selective layers. Here, we introduce and comprehensively investigate an CNGS-based solar-cell architecture using SCAPS-1D, with In2S3 and MoTe2 serving as the electron and hole-transport layers respectively. The analysis of energy-band profiles, electric fields, carrier distributions, and generation-recombination characteristics reveals the mechanisms governing carrier separation and extraction across the heterojunctions. Systematic optimization of layer thickness, doping density, bulk and interface defect densities, recombination coefficients, parasitic resistances, temperature, and illumination intensity identifies the key factors limiting device performance. The optimized device is predicted to achieve a power conversion efficiency (PCE) of 28.44% with a open-circuit voltage (VOC) of 0.984 V, short-circuit current density (JSC) of 34.39 mA/cm2, and fill factor (FF) of 84.04%, under AM1.5G illumination at 300 K. This simulated efficiency exceeds the previously reported 6.25-21.17% range for CNGS-based solar cells considered in this study. The findings establish In2S3/CNGS/MoTe2 as a promising platform for next-generation thin-film photovoltaics and provide physically grounded design guidelines for absorber optimization, interface engineering, and future experimental realization.
Materials Science (cond-mat.mtrl-sci)
Condensation temperature and magnetic phases of trapped coherently coupled Bose gases
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-09-11 20:00 EDT
Sunilkumar V, Rajat, Sandeep Gautam, Arko Roy
We investigate condensation and finite-temperature magnetic phase transitions in a coherently (Rabi) coupled Bose gas confined in a three-dimensional harmonic trap. For the noninteracting system, we derive analytical expressions for the critical temperature and condensate fraction using a semiclassical description of the single-particle spectrum and density of states. At fixed particle number, coherent coupling enhances the critical temperature relative to the uncoupled system, and this enhancement decreases with increasing particle number $ N$ . The finite-size correction, in contrast, lowers the transition temperature, with its effect diminishing for larger $ N$ . We then incorporate repulsive interactions within the Hartree–Fock–Bogoliubov–Popov framework to investigate the finite-temperature phase diagram in the temperature–Rabi coupling plane. The system undergoes successive transitions from a ferromagnetic to a paramagnetic condensate and, at higher temperature, to a thermal gas. The transition boundaries obtained from the vanishing of the condensate fraction show excellent agreement with the analytical Hartree-Fock predictions. We find that the interactions substantially suppress the variation in the condensation temperature with an increase in the coherent coupling.
Quantum Gases (cond-mat.quant-gas)
17 pages, 5 figures
Learning Quantum Matter through Attention in Complex Space
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Mingrui Jing, Erdong Huang, Jizhe Lai, Enji Xiong, Jin-Guo Liu, Xin Wang
Magnetic many-electron wavefunctions require amplitude and phase to be optimized together. Whether a complex internal representation improves this variational search is a practical question for neural wavefunction design. We introduce Complex Psiformer for interacting electrons in a magnetic moiré continuum, combining complex hidden features and Hermitian-magnitude attention with magnetic boundary conditions and fermionic antisymmetry. After the same number of optimization steps, Complex Psiformer reaches lower energies than Real Psiformer in two finite supercells. Both Psiformers also improve on their respective neural Hartree-Fock references. Across five training seeds in the 25-cell system, the mean Complex advantage is 1.458 meV per electron, with a smaller observed spread. A separately trained two-electron Complex state has a smaller energy gap to a finite configuration interaction reference than its Real counterpart. In the Complex states, flux scans show nonmonotonic density correlations and weaker honeycomb mean-density modulation at higher flux, while connected fluctuations persist. Gauge invariant current maps provide a qualitative comparison of local circulation in the optimized states. These benchmarks support the combined architecture as a variational ansatz for studying energies and charge arrangements in finite magnetic systems.
Strongly Correlated Electrons (cond-mat.str-el)
24 pages, 11 figures, GitHub repo: this https URL
Interacting Tomonaga-Lüttinger liquid with impurity for interaction constant $K = 1/2$: Thermopower investigation, entropy variation and heat capacity densities associated with thermoelectric particle transport
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-09-11 20:00 EDT
Abdellah Touati, Redoune Zamoum, Farhi Houssam Eddine
We investigate thermoelectric and thermodynamic properties of a Tomonaga-Luttinger liquid with interaction parameter $ K=1/2$ in the presence of a localized impurity. Using bosonization and refermionization, we derive an exact expression for the thermopower in the nonlinear regime and obtain the corresponding Seebeck coefficient in linear response. At low temperature, the Seebeck coefficient follows a Mott-like relation governed by the energy dependence of the transmission coefficient and is found to be closely related to the entropy per particle. This connection allows us to derive using Kelvin formula the thermopower contribution to the entropy density variation and the charge-carriers contribution to the heat capacity density. Both quantities exhibit Mott-like behavior in the low-temperature regime. We apply our results to a fractional quantum Hall quantum point contact and to a one-channel quantum conductor coupled to an Ohmic environment. Our results demonstrate the close connection between thermoelectric transport and thermodynamic properties in interacting one-dimensional quantum systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
Block entropy area based non-local fermionic mode optimization with gradient disentanglers
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Miklós Antal Werner, Gero Friesecke, Andor Menczer, Kornél Kapás, Örs Legeza
We introduce a systematic block entropy area based mode optimization algorithm for many-body quantum states of interacting fermions represented by matrix product states. From the gradient of a global cost function, the block entropy area, a long-ranged, non-interacting effective disentangler Hamiltonian is formed. We then simulate the time-dependent Schrödinger equation driven by the disentangler Hamiltonian by employing the time-dependent variational principle based on projector splitting, and minimize the cost function. The combination of the density matrix renormalization group with this gradient-based entanglement minimization forms an efficient low-rank iterative ground-state algorithm that also provides an optimized single-particle basis for matrix product state representation. We demonstrate the method on two-dimensional lattice models of interacting fermions and the Fe$ {_4}$ S$ {_4}$ cluster, and show its robustness and superiority over earlier protocols using nearest-neighbor mode rotations and reorderings.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), Computational Physics (physics.comp-ph), Quantum Physics (quant-ph)
6 pages, 3 figures
Piezomagnetism in a model cubic noncollinear altermagnet
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Sudarshan Sharma, Luca Buiarelli, Richard Spieker, Ivan Jakovac, Damjan Pelc, Turan Birol, Martin Greven
Altermagnets constitute a distinct class of magnetic materials that combine compensated magnetic order with spin-polarized electronic bands, hence carrying characteristics of both antiferromagnets and ferromagnets. Piezomagnetism - the linear relationship between lattice strain and a net magnetic moment - has emerged as smoking-gun evidence of altermagnetism that distinguishes it from antiferromagnetism. Here, we uncover a large piezomagnetic response in MnTe2, a cubic altermagnet with a noncollinear spin arrangement and weak spin-orbit coupling. We combine dilatometry with nuclear magnetic resonance, a bulk local probe, to observe signatures of both direct and inverse piezomagnetism consistent with symmetry considerations and first-principles calculations. The dilatometry measurements reveal a shear deformation proportional to an applied magnetic field, while magnetic resonance detects a ferromagnetic moment induced by shear strain. The respective results for the piezomagnetic coupling strength are in good agreement, and they are captured by first-principles results. These findings for simple binary MnTe2 position this material as a model altermagnet, demonstrate the utility of nuclear magnetic resonance in investigations of piezomagnetism, and open new avenues for multimodal strain and magnetic-field control in spintronic and memory applications.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
15 pages, 8 figures
Sub-cycle doublon-holon dynamics in one-dimensional Mott insulators revealed by two-color high-harmonic spectroscopy
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Lance Hatch, Aditya Verma, Eric Schultz, Hanjun Yang, Priscila Rosa, Genda Gu, Igor Zaliznyak, Giulio Vampa, Laimei Nie, Hanzhe Liu
Solid-state high-harmonic spectroscopy is becoming an emerging tool for probing nonequilibrium many-body dynamics. Yet, direct measurements of strongly driven, sub-optical-cycle dynamics in correlated materials during high-harmonic emission remain largely unexplored. Here, we measure high-harmonic emission chirp in a prototypical one-dimensional Mott insulator, which encodes strongly driven doublon-holon dynamics at sub-optical-cycle timescales. We observe a positive chirp for above band gap harmonics, indicating that high harmonics are dominated by doublon-holon recombinations. We further show a harmonic order-dependent dephasing, which can be understood through different doublon-holon excursion distances associated with each harmonic. These results reveal coherent doublon-holon dynamics and their ultrafast dephasing in Mott insulators, which is relevant to other nonequilibrium light-induced phenomena, such as Floquet engineering.
Strongly Correlated Electrons (cond-mat.str-el), Optics (physics.optics)
High-fidelity k$\cdot$p representations of first-principles electronic band structures through covariant renormalization
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
The k$ \cdot$ p method can be applied directly to first-principles energies and momentum matrix elements, but the resulting models converge slowly with the number of bands and are inexact wherever the underlying Hamiltonian is nonlocal. We show that both limitations can be largely removed by renormalizing the eigenvalue spectra of the Hermitian momentum matrices. These spectra are gauge invariant, and are identical for symmetry-related Cartesian components, hence scaling the recurring magnitudes provides a modest set of parameters that preserves degeneracies and crystal symmetry without needing to construct a symmetry-adapted basis. We choose to renormalize the models against reference eigenvalues and band velocities on rays out of a high-symmetry point. For GaP, a 15-band model can reproduce the band structure in the near-gap reference regions within a few meV. For zincblende and wurtzite AlN, similar accuracy requires 30- or 66-band models, which in the case of zincblende is traced to the strong warping in the [110] direction. The scheme readily generalizes to rocksalt PbTe, which includes spin-orbit coupling, and has L-centered valence and conduction band extrema. Further, we demonstrate, for GaP, how compact four-band Hamiltonians can be obtained by downfolding within the same renormalization scheme. Moreover, by changing the fitting regime to encompass the entire Brillouin zone, the scheme can be used to generate full-zone models that reproduce the density of states. The practical utility is illustrated with a 59-band k.p model for GaP, which can be evaluated on meshes far denser than the reference calculation, that in turn can be used both to resolve fine features in the density of states and to compute the hole conductivity at low temperature.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Computational Physics (physics.comp-ph)
9 pages, 10 figures, 1 table
High-Temperature ferromagnetism from site-selective filling in (Fe,Ni)$_{6-δ}$GeTe$_2$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Tyler L. Werner (1), Jonathan T. Reichanadter (2 and 3), Xiang Chen (2 and 4), Pranab K. Nag (5 and 6), Luna Y. Liu (1), Yu-Tsun Shao (7 and 8), Hongrui Zhang (9), Mingyang Guo (10), Wenxin Li (1), Zhibo Kang (1), Han Wu (11 and 12), Makoto Hashimoto (13), Donghui Lu (13), Turgut Yilmaz (14), Elio Vescovo (14), Sung-Kwan Mo (15), Barat Achinuq (15), Alexei Fedorov (15), Jacob C. Ruff (16), Ming Yi (11 and 12), Qiong Ma (10 and 17), David A. Muller (7 and 18), Eduardo H. da Silva Neto (1, 5 and 6), Robert J. Birgeneau (2 and 4), Jeffrey B. Neaton (2 and 19), Yu He (1) ((1) Department of Applied Physics, Yale University, New Haven, USA, (2) Department of Physics, University of California, Berkeley, Berkeley, USA, (3) Department of Electrical Engineering and Computer Science, University of California, Berkeley, Berkeley, USA, (4) Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, USA, (5) Department of Physics, Yale University, New Haven, USA, (6) Energy Sciences Institute, Yale University, West Haven, USA, (7) School of Applied and Engineering Physics, Cornell University, Ithaca, USA, (8) Mork Family Department of Chemical Engineering and Materials Science, University of Southern California, Los Angeles, USA, (9) Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, USA, (10) Department of Physics, Boston College, Chestnut Hill, USA, (11) Department of Physics and Astronomy, Rice University, Houston, USA, (12) Rice Center for Quantum Materials, Rice University, Houston, USA, (13) Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, USA, (14) National Synchrotron Light Source II, Brookhaven National Laboratory, Upton, USA, (15) Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, USA, (16) Cornell High Energy Synchrotron Source, Cornell University, Ithaca, USA, (17) Schiller Institute for Integrated Science and Society, Boston College, Chestnut Hill, USA, (18) Kavli Institute at Cornell for Nanoscale Science, Cornell University, Ithaca, USA, (19) Kavli Energy Nanosciences Institute at Berkeley, Berkeley, USA)
The discovery of high-temperature ferromagnetism in the metallic van der Waals (vdW) system Fe$ _N$ GeTe$ _2$ has brought two-dimensional (2D) magnets into technologically relevant temperature scales. Specifically at N = 5, dilution of magnetic moments by nickel substitution counterintuitively achieves a record high Curie temperature of 478~K. Unraveling the origin of this nickel-substitution-induced enhancement is complicated by the compound’s structural complexity, coexistent itinerant and local magnetic contributions, and mesoscopic compositional domains. Through coordinated structural and electronic characterization, we identify that the high-T$ _C$ magnetic phase arises from a strain-stabilized Fe$ _6$ GeTe$ _2$ nano-precipitate. Combining first-principles calculations and spin- and angle-resolved photoemission spectroscopy (ARPES), we uncover a site-specific electronic landscape in which interior iron atoms primarily host localized moments while the outer iron atoms neighboring the tellurium layers produce spin-polarized itinerant carriers that cross the vdW gap. The large energy cost associated with homogeneous nickel substitution is found to favor the spontaneous precipitation of the crystallographically and electronically ``clean’’ high-T$ _C$ phase. Finally, we compare metal-rich vdW magnets with binary magnetic alloys, and discuss the unifying roles of nano-precipitates in stabilizing otherwise unattainable bulk phases. Our work provides mechanistic insights into the record-high T$ _C$ ferromagnetism in (Fe,Ni)$ _{5+\delta}$ GeTe$ _2$ , establishing a rigorous foundation for the atomic engineering of vdW magnetic metals informed by direct electronic signatures.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
16 pages, 8 figures
Sparse data limit what a mechanistic corrosion model can predict
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-09-11 20:00 EDT
Conrard Giresse Tetsassi Feugmo
Mechanistic corrosion models are routinely fitted with four to six parameters to a few measurements and extrapolated across service lifetimes, yet whether the data determine them is rarely tested. We identify a reduced point defect model for the duplex oxide on Nb-stabilized AISI 347 in simulated boiling-water-reactor water from published depth profiles at three exposure times, by differentiable inversion graded against a closed-form reference. Profile likelihood, a 1000-member bootstrap and a prior-relaxation test agree that one of the five parameters is undetermined and a second only weakly so, and that 95% of the fit statistic rests on three chromium points. The kinetics track an empirical power law over the calibration window but diverge from it by a factor of 3.5 to 6.3 at ten years, outside the propagated uncertainty band. That separation, not the thickness it brackets, is what these data determine; an exposure near 3000 hours would resolve it.
Materials Science (cond-mat.mtrl-sci)
Low temperature thermodynamics of $S_{\mathrm{eff}}=1/2$ triangular lattice quantum spin liquid candidate TlYbS$_2$
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Bishnu P. Belbase, Arjun Unnikrishnan, Piyush Chhallare, Mohan B. Neupane, Eun Sang Choi, Sebastian Erdmann, Muhammad U. Akbar, Mamoun Hemmida, H.-A. Krug von Nidda, Philipp Gegenwart, Arnab Banerjee
Geometrically frustrated triangular-lattice antiferromagnets exhibit a delicate competition between magnetic order and quantum spin liquid (QSL) behavior, with the Yb-based delafossite family $ A$ Yb$ X_2$ providing a structurally clean platform for exploring this physics. Here, we report a comprehensive study of single-crystal TlYbS$ 2$ using DC magnetization, AC susceptibility, electron spin resonance (ESR), and specific heat measurements extending from room temperature to the millikelvin regime. Single-crystal X-ray diffraction confirms a trigonal $ R\bar{3}m$ structure comprising well-separated triangular layers of Yb$ ^{3+}$ ions with no detectable site disorder. At zero field, a weak thermodynamic anomaly is observed near $ 530$ mK, which may indicate the onset of a weakly ordered state similar to that reported in KYbSe$ 2$ . Below $ 300$ mK, the zero-field magnetic specific heat follows $ C{\rm m}\propto T^{1.8}$ , close to a quadratic temperature dependence, in contrast to the linear temperature dependence reported for the sister compound TlYbSe$ 2$ , which has been described in terms of the interplay between spinons and thermally excited gauge-flux excitations. Magnetization and ESR measurements establish pronounced easy-plane magnetic anisotropy, with $ g\perp/g\parallel \approx 6.9$ . The anomaly near $ 530$ mK exhibits a strongly anisotropic response to magnetic field. For $ H\perp c$ , it remains visible up to approximately $ 2$ T and continuously evolves toward a field-induced ordered phase above approximately $ 2.5$ T, followed by a sequence of field-induced phases that includes a $ 1/3$ magnetization plateau between approximately $ 5$ and $ 8$ T and full polarization near $ 17$ T. In contrast, for $ H\parallel c$ , the anomaly weakens and is suppressed near $ 3$ T, consistent with the recently reported confinement–deconfinement transition from an ordered state to a field-induced QSL.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
11 Pages, 5 figures
Effective Ionic Valence and Local Magnetic Moment in Kagome Superconductors
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-09-11 20:00 EDT
Ruoshi Jiang, Zi-Jian Lang, Yuzki Oey, Andrea Capa Salinas, Stephen D. Wilson, Yongwei Li, Ilya Shipulin, Yiwen Zhang, Deng Hu, Zhiwei Wang, Hans-Henning Klauss, Zurab Guguchia, Vadim Grinenko, Wei Ku
In order to understand the unexpected similarity and the correlated behavior in kagome superconductor families AV$ _3$ Sb$ _5$ (A = K, Rb, Cs) and ATi$ _3$ Bi$ _5$ (A = Rb, Cs), we investigate the Hartree-scale local electronic structure of these systems. Our result indicates that V and Ti ions are both of 2+ valence such that the corresponding itinerant carrier densities are similar, and the difference in electron count is instead reflected in their quantum fluctuating ionic magnetic moments. However, due to the frustrated lattice geometry of these materials, such local moments are difficult to experimentally observe via standard probes. For verification, we systematically introduce nonmagnetic Sn impurities to locally relieve the geometric frustration and experimentally demonstrate the existence of well-defined local magnetic moments via magnetic susceptibility and muon spin rotation or relaxation ($ \mu$ SR) measurements. All experiments discover a systematic increase of magnetic susceptibility upon increasing nonmagnetic impurity level. Our discovered ionic moments suggest a paradigm shift from the existing itinerant carrier-only picture to one incorporating strong correlation from local ionic spins. The associated interatomic and local-itinerant correlations offer a solid ground for the emergence of the observed rich correlated behavior in this new family of superconducting materials.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
17 pages, 11 figures
Phys. Rev. X 16, 031064 (2026)
Research Square
A Nanoscale Pixel Architecture for High-Efficiency
AlGaN Ultraviolet-C (UV-C) Light-Emitting Diodes
Article | Nanophotonics and plasmonics | 2026-09-10 20:00 EDT
Sharif Sadaf
AlGaN ultraviolet-C (UV-C) light-emitting diodes hold great promise for disinfection, water purification, and non-line-of-sight communication, yet their adoption is constrained by low external quantum efficiency (EQE) arising from high threading dislocation densities, poor p-type doping, and inefficient extraction of dominant transverse-magnetic (TM) polarized emission. Here, we demonstrate the first top-down fabricated ~400 nm AlGaN UV-C nanopixel array, and present a pixel-area driven experimental comparison of planar micropixel and nanopixel UV-C LEDs over a [20 μm]2 footprint, supported by a systematic micropixel scaling study from [60 μm]2 to [20 μm]2. The nanopixel arrays deliver peak power densities exceeding 10 W/cm2, with an EQE of >1%. Electromagnetic simulations using the finite-difference time-domain (FDTD) method show a ~3-4× enhancement in TM-polarized light extraction compared to planar counterparts. Furthermore, Monte Carlo statistical modelling reveals a substantial reduction in dislocation density within nanoscale pixels, which further contributes to the light output enhancement of the nanopixels. These results establish top-down nanopixel architectures as a scalable route to high-efficiency UV-C emitters, identify UV-transparent sub-micrometer planarization as the key remaining materials challenge, and delineate the design space for further efficiency gains in the challenging deep UV spectral range.
Research Square:rs-10706593 (2026)
Posted on Research Square
Physical sciences/Nanoscience and technology/Nanoscale devices/Nanophotonics and plasmonics, Physical sciences/Materials science/Nanoscale materials/Nanowires
Observation of robust corner states in photonic crystals without global symmetries
Article | Photonic crystals | 2026-09-10 20:00 EDT
Zhi-Yuan Li, Zitao Ji, Jianfeng Chen, Yidong Zheng, Zhaogang Dong
Robust corner states have attracted considerable attention in recent years, particularly in photonic systems. They are typically realized in second-order topological insulators, including shrunken-expanded lattices and breathing Kagome lattices, where global symmetries are essential in their formation. This reliance on symmetry, however, can make these states highly sensitive to structural disorder. Here, we propose and experimentally demonstrate a class of robust corner states in photonic crystals that require neither global symmetry nor nontrivial topology. By locally tailoring the corner geometry of an otherwise topologically trivial structure, we create strongly localized modes that remain stable under both position and radius disorder. These states are not accidental; rather they originate from a pair of Dirac points in the bulk band structure. Geometric tuning shifts the flatband edge states connecting the Dirac points into an otherwise trivial bandgap, thereby inducing strongly localized corner states. Our findings uncover a previously overlooked class of symmetry-independent, disorder-resilient corner states, extend robust localization beyond conventional topological protection, and provide a route toward light localization in all-dielectric photonic systems.
Research Square:rs-10862634 (2026)
Posted on Research Square and Under Review at Nature Portfolio
Physical sciences/Optics and photonics/Optical materials and structures/Photonic crystals, Physical sciences/Physics/Optical physics/Sub-wavelength optics