CMP Journal 2026-06-09
Statistics
Nature: 1
Nature Nanotechnology: 1
Nature Physics: 3
arXiv: 120
Nature
A unicellular relative links aggregative multicellularity to animal origins
Original Paper | Cell adhesion | 2026-06-08 20:00 EDT
Ruibao Li, Jennah E. Dharamshi, Kyle Kwok, Iñaki Ruiz-Trillo, Joseph P. Gerdt
How animals evolved complex multicellularity from their unicellular ancestors remains unanswered. Unicellular relatives of animals exhibit simple multicellularity through clonal division, formation of multinucleate coenocytes, or aggregation. 1 Therefore, animal multicellularity may have evolved from one (or a combination) of these behaviours. Aggregation has classically been dismissed as a means to complex multicellularity. 2 However, aggregation occurs in many extant animal cells and has also been recently described in three close unicellular relatives of animals (the choanoflagellates Salpingoeca rosetta and Choanoeca flexa, and the filasterean Capsaspora owczarzaki). 3-5 It is unclear whether aggregation in these species is derived or ancestral, and its relevance for animal origins remains unknown. To fill this gap, we investigated whether an additional close unicellular relative of animals can undergo aggregation. We discovered that the marine free-living bacterivorous filasterean Ministeria vibrans 6 forms homogeneous aggregates with reproducible kinetics that have long-term stability, and that improved feeding and mating may be evolutionary drivers of this aggregation. Notably, we found that homologs of many animal multicellularity genes involved in cell adhesion, signalling, and transcriptional regulation were deployed during the aggregation process, indicating that they may have been used for aggregation in the unicellular ancestors of animals before being co-opted into animal multicellular development. Thus, our results imply that aggregative multicellularity was key to the development of the multicellular animal genetic toolkit.
Cell adhesion, Evolutionary developmental biology, Evolutionary genetics, Nutrient signalling, Symbiosis
Nature Nanotechnology
Direct evidence of metal-ligand redox processes in positive electrodes during lithium-based battery operation
Original Paper | Batteries | 2026-06-08 20:00 EDT
Galo J. Páez Fajardo, Daniela E. Dogaru, Hrishit Banerjee, Muhammad Ans, Matthew J. W. Ogley, Veronika Majherova, Gerard Bree, Innes McClelland, Shohei Hayashida, Pascal Puphal, Masahiko Isobe, Bernhard Keimer, Pardeep K. Thakur, Tien-Lin Lee, Dave C. Grinter, Pilar Ferrer, Serena A. Cussen, Matthias Hepting, Louis F. J. Piper
Describing lithium-based battery positive electrodes based on different transition metal or oxygen-redox regimes can cause confusion in understanding metal-ligand hybridization, oxygen dimerization and degradation processes. Therefore, it is urgent to investigate the electronic structure of these materials and identify the role each cation and anion has in charge compensation at the subnanoscale. Here, using X-ray resonance photoemission spectroscopy, single-impurity Anderson models, spectral simulations and theoretical calculations, we examine redox mechanisms in positive electrodes during lithium-based battery operation. This approach reconciles the redox description of two positive electrode active materials–LiMn0.6Fe0.4PO4 and LiNiO2–in terms of varying degrees of charge transfer using the Zaanen-Sawatzky-Allen framework. In LiMn0.6Fe0.4PO4, the lack of strong hybridization indicates that the capacity results from the depopulation of metal 3d states, that is, conventional metal redox. However, in cells with LiNiO2-based positive electrodes, negative charge transfer dominates, and redox occurs through the formation and elimination of ligand-hole states. These results clarify the role of oxygen in Ni-rich systems and provide a framework to explain how the charge/discharge capacities are linked to oxygen-dominated states in highly covalent systems, without the need to consider oxygen dimerization.
Batteries, Electronic properties and materials, Materials for energy and catalysis, Theoretical chemistry
Nature Physics
Crossover of quasi-localized dynamics and diffusion in supercooled liquids
Original Paper | Glasses | 2026-06-08 20:00 EDT
Federico Caporaletti, Simone Capaccioli, Dimitrios Bessas, Aleksandr I. Chumakov, Alessandro Martinelli, Francesco Dallari, Giulio Monaco
Secondary relaxation, also known as βJG relaxation, is a dynamical process observed in supercooled liquids and glasses. It is distinct from the slower, so-called α relaxation, which is associated with particles escaping the cages formed by their surrounding neighbours. The secondary relaxation affects several properties of the glass, including the crystallization propensity and mechanical response. Traditionally studied via dielectric and mechanical spectroscopy, the βJG relaxation is often linked to quasi-localized particle motion. Here we use a wavevector-resolved X-ray technique to access microscopic, real-space information on the βJG relaxation in a hydrogen-bonded glass former and show that the α and βJG relaxations cannot be described as two independent processes. Moreover, we provide evidence that the βJG relaxation is associated with a sublinear growth of the mean-squared molecular displacement preceding the onset of diffusion. Our findings thus clarify that the βJG relaxation can be described as the critical rattling of molecules within the cage formed by their neighbours just before escaping from it.
Glasses, Statistical physics, Structure of solids and liquids
Observation of exact quantum critical states
Original Paper | Phase transitions and critical phenomena | 2026-06-08 20:00 EDT
Wenhui Huang, Xin-Chi Zhou, Libo Zhang, Jiawei Zhang, Yuxuan Zhou, Bing-Chen Yao, Zechen Guo, Peisheng Huang, Qixian Li, Yongqi Liang, Yiting Liu, Jiawei Qiu, Daxiong Sun, Xuandong Sun, Zilin Wang, Changrong Xie, Yuzhe Xiong, Xiaohan Yang, Jiajian Zhang, Zihao Zhang, Ji Chu, Weijie Guo, Ji Jiang, Xiayu Linpeng, Wenhui Ren, Yuefeng Yuan, Jingjing Niu, Ziyu Tao, Song Liu, Youpeng Zhong, Xiong-Jun Liu, Dapeng Yu
Anderson localization describes the suppression of wave transport in disordered media. In quantum systems, it gives rise to extended, localized and critical eigenstates, with the latter showing properties between the other two. Characterizing critical states is challenging because it requires analysis in the thermodynamic limit or a universal mechanism that identifies them. Here we experimentally realize critical states in a programmable quasiperiodic mosaic model with tunable couplings and on-site potentials using a system of superconducting qubits. By measuring time-evolving observables, we identify coexisting delocalized dynamics and incommensurately distributed zeros in the couplings, which characterize the critical states. We map the transition from localized to critical behaviour and show that critical states persist until strong long-range couplings remove the quasiperiodic zeros. Finally, we resolve an energy-dependent transition between localized and critical states, revealing anomalous mobility edges.
Phase transitions and critical phenomena, Quantum simulation
Bilayer excitons in the Laughlin fractional quantum Hall state
Original Paper | Bose-Einstein condensates | 2026-06-08 20:00 EDT
Ron Q. Nguyen, Naiyuan J. Zhang, Navketan Khurana-Batra, Sarah Alkidim, Xiaoxue Liu, Kenji Watanabe, Takashi Taniguchi, D. E. Feldman, J. I. A. Li
The Laughlin state provides a description for a universal class of fractional quantum Hall effects that arise in two-dimensional electron systems subjected to strong perpendicular magnetic fields. Conventionally described by a single-component wavefunction, the Laughlin state features fractionally charged quasiparticles that result from correlations within one electronic layer. Here we explore a bilayer situation with interlayer Coulomb coupling between two intralayer Laughlin states that creates excitons between them in a quantum Hall graphene structure. Although quasiparticle excitations typically exhibit charge gaps of tens of kelvins, we observe that this energy scale is lowered through interlayer excitonic pairing between quasiparticles and quasiholes. We identify these excitons in our transport measurements and show that they belong to a category of charge-neutral anyons, thus opening an avenue for investigating exotic quantum statistics and phases of matter.
Bose-Einstein condensates, Quantum Hall, Topological matter
arXiv
Finite-temperature formation of magnetic plateaus and simplex liquid states on the frustrated ruby lattice
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Antonio Francesco Mello, E. Miles Stoudenmire, Joseph Tindall
Geometric frustration in quantum systems can stabilize unconventional phases of matter that avoid traditional magnetic ordering at low temperatures. Here, we observe this phenomenon while mapping out the finite temperature phase diagram of the spin-1/2 Heisenberg antiferromagnet on the ruby lattice with next-nearest-neighbor interactions. Using an infinite tensor network state (iTNS) optimized and measured with belief propagation (BP) and corrections to BP, we observe the low temperature formation of stable magnetic plateaus at various magnetic field strengths. We find these plateaus host a novel `simplex liquid state’ – a disordered phase involving strongly paired spin simplices that retains non-zero residual entropy due to an exponentially large subspace of crystalline configurations. We accurately quantify the energy gap associated with these states and show that, as the temperature of the system is lowered, it does not go through a phase transition to reach them: the heat capacity remains finite and continuous at all observed temperatures. Our work demonstrates how BP-based tensor network techniques provide a powerful route to understanding frustrated quantum magnets at finite temperature.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
Main text: 6 pages, 4 figures. Comments are welcome
Topological Melting of Magnetic Stripes and the Emergence of Macroscopic d-wave Superconductivity in the 2D Hubbard Model
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
The exact ground state of the two-dimensional Hubbard model is critical for understanding cuprate superconductivity. Previous numerical studies on narrow cylinders found insulating, static stripes that inherently suppress superconductivity. Here, using constrained-path auxiliary-field quantum Monte Carlo on isotropic lattices up to $ 24 \times 24$ sites, we show static stripes are boundary artifacts. The true 2D thermodynamic limit yields a topologically melted fluid of dynamically fluctuating magnetic pockets. Furthermore, we reveal the microscopic real-space origin of cuprate particle-hole asymmetry. Hole doping actively melts the magnetic background, driving a Lifshitz transition that unleashes macroscopic $ d_{x^2-y^2}$ phase coherence at an optimal $ x \approx 0.150-0.200$ . Conversely, electron doping preserves rigid antiferromagnetic domains, confining carriers to narrow fault lines that optimally saturate early at $ x \approx 0.100$ . By extracting the macroscopic off-diagonal long-range order across both regimes, we perfectly recover the skewed phenomenological superconducting dome. Our parameter-free theoretical curve aligns with empirical Uemura and Božović scaling relations, capturing the underdoped emergence, distinct optimal peaks, the 1/8 anomaly suppression, and overdoped collapse. These results prove that robust d-wave superconductivity is the intrinsic ground state of the pure Hubbard Hamiltonian.
Strongly Correlated Electrons (cond-mat.str-el), Superconductivity (cond-mat.supr-con)
61pages, 23 figures
Polyethylene-based thermo-mechanically recyclable stretchable yarns for circular sustainable textiles
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
SeongHyeon Kim, Duo Xu, Volodymyr Korolovych, Domingo R. Flores-Hernandez, Kaniz Moriam, Daniel J. Braconnier, Svetlana V. Boriskina
Most high-performance elastic textiles rely on yarns composed of chemically dissimilar polymers, rendering them difficult to recycle. Here, we demonstrate fully thermo-mechanically recyclable stretchable yarns composed of polyethylene (PE) family materials. Inspired by structure-property relationships in natural materials, we engineer a library of melt-spun PE fibers spanning mechanical properties from elastomeric to functional by tuning polymer crystallinity and chain orientation. These fibers are assembled into core-sheath yarns comprising an olefin block copolymer elastic core and a high-strength PE sheath, forming a helical architecture. The resulting yarns exceed mechanical performance of commercial PET-spandex yarns while maintaining full recyclability. We further show that PE homopolymers and copolymers can be jointly melt-processed and recycled without phase separation or loss of performance. This approach enables stretchable recyclable textiles from fibers with previously demonstrated cooling, moisture-wicking and stain-resisting performance and provides a scalable pathway toward circular garments compatible with existing polyethylene recycling streams.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
Stability and thermodynamic properties of bound magnetic polarons in ferromagnetic semiconductors: Beyond the Gaussian approximation
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
The formation of bound magnetic polarons (BMPs) is traditionally described using a Gaussian approximation for host magnetization fluctuations. While successful for diluted magnetic semiconductors, this approach fails for ferromagnetic semiconductors like GdN near their Curie temperature Tc, where diverging susceptibility yields unphysical instabilities. We extend the BMP theory beyond the Gaussian approximation by rigorously incorporating cubic and quartic fluctuations of the Ginzburg-Landau-Wilson functional. Two consistent extensions of the Dietl-Spalek framework are presented: (i) a non-local treatment valid for finite spin correlation lengths xi (to first order in lambda) and (ii) a non-perturbative resummation of dominant local fluctuations to a closed exponential form in the strict local limit xi to 0. The latter is justified by a novel polaronic Ginzburg criterion showing that constraint-induced non-localities are suppressed by O(1/N_eff) with N_eff >> 1. Crucially, the theory incorporates variational optimization of the donor orbital size, capturing magnetic self-trapping even above Tc. When applied to GdN (Tc = 55 K), the model eliminates the Gaussian divergence and predicts stable, ferromagnetically ordered BMPs with a non-zero spontaneous spin splitting Delta_0 deep into the paramagnetic phase. For a realistic exchange coupling Jc = 400 meV, the effective polaron ordering temperature reaches T\ast = 155-160 K. The model further suggests an optimal donor-concentration window near the metal-insulator transition where enhanced dielectric screening maximizes T\ast. These results establish a microscopic mechanism for persistent BMP-mediated ferromagnetism well above Tc.
Strongly Correlated Electrons (cond-mat.str-el)
AI-assisted manuscript preparation. See Acknowledgments section for details
Shear-Induced Structural Convergence but Formation-History-Dependent Yielding in Sequentially Gelled Binary Colloidal Networks
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Alexander Kaltashov, Safa Jamali
Multicomponent colloidal gels can exhibit mechanical responses that depend not only on interaction strengths but also on the temporal pathway by which their networks form. Here, we use particle-based simulations to investigate the steady-shear deformation of binary colloidal gels assembled by sequential gelation with tunable delay time and dominant interspecies attractions. Although varying the gelation delay produces markedly different quiescent morphologies, ranging from well-mixed networks to coarse shell-core structures, steady shear drives the systems toward structurally convergent, mixed states as quantified by cluster, connected-component, and coordination analyses. This structural convergence, however, does not imply rheological equivalence. The transient stress response remains strongly dependent on gelation delay and interspecies attraction strength. For moderate interspecies attractions, increasing delay enhances the stress overshoot, particularly at high shear rates. For stronger interspecies attractions, initially heterogeneous gels exhibit two-step yielding at low shear rates, indicating distinct deformation and restructuring processes. These results show that sequential gelation can imprint a persistent rheological memory in binary colloidal gels, even when shear substantially erases differences in common structural descriptors.
Soft Condensed Matter (cond-mat.soft)
10 pages, 5 figures
MatMind: A Structure-Activity Knowledge-Driven Generative Foundation Model for Materials Science
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Zhan’ao Yao, Boxuan Zhang, Jingyuan Shu, Xiaoyu Wu, Rongyan Wang, Linjing Li, Dajun Zeng, Yudong Yao, Tingwei Chen, Youwei Wang, Xiaolin Zhao, Jiahui Shi, Jianjun Liu
Progress in AI-driven crystal materials science has so far been carried by narrow architectures purpose-built for individual tasks – graph neural networks for property prediction, diffusion and flow-matching models for crystal generation – each excelling within its niche yet unable to act as a shared backbone across the full spectrum of materials problems. Generative large language models offer a fundamentally different paradigm, in which structural representation, quantitative prediction, and structure-activity reasoning can be unified within one model, but the materials community has yet to see this paradigm realized at a level competitive with established narrow specialists. Here we present MatMind, a generative foundation model purpose-built for crystal materials science under this paradigm, developed through the coordinated activation of structure-activity knowledge and physics-informed feedback within a progressive training framework – combining structure-activity knowledge injection, a dual-head architecture that jointly trains language reasoning and numerical regression in a shared representation space, and multi-objective physics-informed reinforcement learning over stability, novelty, and structural diversity. Across three task families, MatMind attains the lowest mean absolute error on energy above hull, bulk modulus, and band gap – surpassing graph neural network predictors purpose-built for these tasks – reaches an S.U.N. rate of 65.3% on unconditional crystal generation, and achieves a comparable multiplicative improvement on magnetization-density-conditioned generation, where only 21 positive samples exist within over 600000 training entries. By matching or surpassing narrow specialists on their own ground while operating within a single unified model, MatMind shows that the LLM-based paradigm can serve as a viable backbone for crystal materials science going forward.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI)
29 pages, 5 figures, including references
Phase diagram of magnetic $S^3$ Skyrmions on three-dimensional lattices and the toroidal antiSkyrmion
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Niccolò Francini, Stefano Bolognesi, Sven Bjarke Gudnason, Roberto Menta
Magnetic Skyrmions are planar solitons stabilized by the Dzyaloshinskii-Moriya interaction (DMI) and realized in chiral magnets. We study their natural three-dimensional generalization: a sigma model from $ \mathbb{R}^3$ to $ S^3$ with a four-component magnetization vector, stabilized by a one-derivative term which is a generalized DMI. We utilize two SO(3)-invariant generalized DMIs discovered recently: an “$ \alpha$ -term” supporting a spherically symmetric hedgehog Skyrmion and a “$ \beta$ -term” supporting an axially symmetric Skyrmion that splits into two half-Skyrmions connected by a magnetic string of negative tension, a phenomenon we call “anti-confinement”. We derive a cubic-lattice discretization that reproduces both continuum theories at long wavelengths and use Monte Carlo simulations to map the finite-temperature phase diagram. We identify spin-spiral, magnetic-string-lattice, Skyrmion-lattice, and antiSkyrmion-lattice phases, as well as a mixed-topology regime with fractional $ S^3$ charges localized at string bends. We find, for the first time in the literature to the best of our knowledge, a toroidal (anti-)soliton of unit charge. Our results establish a theoretical and computational framework for three-dimensional topological magnetic textures in systems whose order-parameter manifold is $ S^3$ .
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), High Energy Physics - Theory (hep-th)
14+4 pages, 11 figures
Detecting Exciton Condensation through Charge Transport in Semiconductor Heterostructures
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Caterina Zerba, Léo Mangeolle, Michael Knap
Direct evidence of exciton condensation in semiconductor heterostructures remains elusive. Here we propose charge transport of doped carriers as a probe of exciton condensation in transition-metal dichalcogenide heterostructures and identify distinct experimental signatures. First, condensation suppresses the phase space for carrier scattering, leading to a reduction in resistivity, that provides a general diagnostic of exciton condensation. Second, in heterostructures with a tunable solid-state Feshbach resonance, condensate-induced hybridization between doped carriers and trion bound states qualitatively modifies transport. In particular, near resonance, this hybridization yields a negative effective mass and a corresponding sign reversal of the Hall resistivity. These results establish charge transport as a promising route for detecting and characterizing exciton condensation in semiconductor heterostructures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Gases (cond-mat.quant-gas), Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
6+7 pages, 3+1 figures
Machine learning assisted molecular dynamics of charge-transfer mechanisms at Li/Ga-doped Li$_7$La$_3$Zr$2$O${12}$ (LLZO) interfaces
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Arseniy S. Burov, Artem M. Abakumov, Dmitry A. Aksyonov
Interfacial charge transfer between solid electrolytes (SEs) and Li metal is a key factor limiting all-solid-state battery performance. Conventional density functional theory and nudged elastic band calculations neglect many-body correlations and finite-temperature effects, which can lead to inaccurate activation barriers. Here, we trained moment tensor potentials (MTPs) for garnet LLZO systems (t-LLZO, c-LLZO, and Ga-LLZO) and Li metal, enabling machine-learning molecular dynamics (MLMD) simulations of Li$ ^+$ diffusion in the bulk and at Li/SE interfaces. We also introduce a residence-time window method that filters out ion rattling and isolates genuine charge-transfer events. The resulting charge-transfer activation energies are low: 167 meV at the Li/Ga-LLZO interface and 200 meV in Ga-LLZO, corresponding to resistances of $ \sim , 10^{-5} , \Omega ,\mathrm{cm}^{2}$ . These results indicate that intrinsic Li/Ga-LLZO charge transfer is not rate-limiting. Overall, our findings clarify the fast interfacial kinetics in Li/LLZO systems, and the proposed methodology can aid further interface optimization in solid-state batteries.
Materials Science (cond-mat.mtrl-sci)
Length-resolved Operator Growth and Path-Entropy Obstructions to Many-Body Localization
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-09 20:00 EDT
For the disordered Ising chain with transverse and longitudinal fields, where couplings and fields are drawn from strictly positive distributions, Cao~\cite{Cao} has shown that the moments $ \mu_{2k} = |[H,\sigma^z_0]^{(k)}|2^2$ grow almost factorially, $ \mu{2k}^{1/(2k)}\sim k/\ln k$ , and thus asymptotically at the maximal allowed rate. We generalize this result by resolving the operator norm in support length and show that the weight at length $ \ell_k \sim k/\ln k$ already exhibits almost factorial growth, $ |[H,\sigma^z_0]^{(k)}_{\ell_k}|_2 \gtrsim (k/\ln k)^k$ . This implies maximal spatial delocalization of local operators and, in particular, rules out dynamical locality – the strongest form of many-body localization – at any disorder strength. We further establish rigorously a finite-size crossover scale $ L\sim (W/J)^2$ , where $ W$ is the disorder and $ J$ the coupling strength. For $ L\lesssim (W/J)^2$ numerical studies only access a pre-asymptotic regime. Finally, we identify a structural path-entropy obstruction to perturbative LIOM constructions, based on the almost factorial branching of operator content and independent of resonance effects; the same mechanism strongly suggests ballistic real-time operator spreading, so sub-ballistic or localized dynamics would require a presently unidentified cancellation principle acting on almost factorially many disorder-dependent paths with random amplitudes.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Statistical Mechanics (cond-mat.stat-mech), Strongly Correlated Electrons (cond-mat.str-el)
Inverse supersymmetry in finite temperature Bose-Fermi mixtures
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-09 20:00 EDT
Zachary Gazzillo, Carlos A. R. Sá de Melo
We investigate nearly degenerate Bose-Fermi mixtures and show that the breaking of generalized supersymmetry (gSUSY) between bosons and fermions, with up to two internal states, manifests itself through the emergence of fermionic Goldstino modes with up to four flavors. In particular, we draw a distinction between typical supersymmetry (SUSY), where bosons have pseudospin 0 and fermions have pseudospin 1/2, and inverse supersymmetry (iSUSY), where bosons have pseudospin 1/2 and fermions have pseudospin 0. In such systems, we highlight that the Goldstino pseudospin is carried by either its constituent fermion (SUSY) or boson (iSUSY). We then distinguish between these two cases by depicting their differing effects on the spectral functions of the bosonic and fermionic atomic species. Lastly, we propose radio-frequency- or microwave-spectroscopy experiments, analogous to momentum (angular) resolved photoemission in condensed matter physics, to measure the pseudospin-dependent spectral functions and detect the emergence of Goldstino modes in mixtures of $ ^{39}$ K and $ ^{40}$ K.
Quantum Gases (cond-mat.quant-gas)
Redox-Active Halide Materials for Cathode Applications
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Electrochemically redox-active halide (eREAL) materials are an emerging class of materials that combine high Li-ion conductivity with transition-metal redox activity, making them promising candidates for cathode or catholyte applications. As a redox-active catholyte, they could significantly increase the energy density of solid-state batteries. In this work, we perform first-principles calculations on Li-M-Cl (M = 3d transition metals) ternaries to establish such a theoretical foundation for their stability and electrochemical activity. We map the phase stability of eREAL structures with varying metal-to-Cl ratio, transition-metal species, oxidation states, and anion frameworks, and compute cation and anion redox potentials. We find that the high ionicity of metal-Cl bonds elevates cation redox potentials above those of conventional oxide cathodes, but also will promote Cl oxidation and Cl-Cl dimerization at high voltages, which may limit the stability of these materials. Anion substitution effectively tunes both cation and anion redox potentials, with F substitution standing out as a viable route to extend the reversible voltage window. Beyond the anion redox issue, eREAL compounds generally exhibit flat voltage profiles, which potentially poses an electrochemical compatibility challenge when paired with active materials that operate at different voltage values or over wider voltage ranges. Collectively, our study provides a comprehensive analysis for redox behavior of eREAL materials, paving the way for their rational design and optimization in next-generation battery applications.
Materials Science (cond-mat.mtrl-sci)
Exact mean-field phase diagram for self-avoiding active particles in a lattice
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Felipe Hawthorne, Cristiano F. Woellner, José A. Freire
We investigate motility-induced phase separation in a lattice gas of self-propelled particles with hard-core exclusion, where an internal director biases particle hopping along the lattice coordination directions while undergoing rotational diffusion, together with a thermal-like translational diffusion. Rather than employing stochastic simulations, we adopt a master-equation formalism within a general mean-field approximation. By linearizing the mean-field master equation around the homogeneous stationary state and applying Bloch’s theorem, the stability analysis is reduced to a $ z$ -dimensional tight-binding eigenvalue problem. A perturbation expansion in the wavenumber near $ \vk = 0$ then yields the spinodal surface in closed analytical form for six Bravais lattices: linear, square, hexagonal, simple cubic, body-centered cubic, and face-centered cubic. The influence of lattice geometry is shown to enter exclusively through a single coefficient $ \mathcal{A}$ which we evaluate exactly for each case. We further show that translational diffusion smooths the interface between the dense and dilute phases. Finally, we determine the rotational probability currents associated with the inhomogeneous stationary states, a distinctive signature of the broken detailed balance underlying active-system dynamics.
Soft Condensed Matter (cond-mat.soft)
Agentic multi-fidelity learning of quasiparticle and excitonic properties
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Arnab Neogi, Aaron Forde, Christopher A. Lane, Sergei Tretiak, Jian-Xin Zhu
Many-body GW-Bethe-Salpeter equation calculations are essential for accurate simulations of electronic structure and optical properties in modern low-dimensional nanomaterials. However, these methods are computationally demanding and can exhibit localized numerical instabilities or convergence failures that are difficult to detect within high-throughput workflows. We introduce an agent-guided multi-fidelity framework for correcting GW-Bethe-Salpeter excited-state landscapes in strained MoS2-WS2 bilayers. Across stacking registries, strain branches and reciprocal-space samplings, the workflow identifies spike-like excursions, near-zero-gap collapse and cross-fidelity inconsistencies associated with fragile long-wavelength dielectric screening. A structural agent evaluates calculations by assigning confidence weights and selectively using a small number of high-accuracy reference points. Machine learning models then transfer information across related systems and apply Gaussian process corrections to recover improved quasiparticle gaps and exciton binding energies, with calibrated uncertainty estimates. The approach corrects numerically induced artifacts without erasing physical strain dependence and substantially improves agreement with higher-fidelity references relative to a no-agent baseline. These results show that reliable surrogate learning for excited-state materials requires explicit diagnosis of numerical fragility, not direct interpolation of raw first-principles data points. The proposed framework is readily transferable to other optoelectronic nanomaterials characterized by strong quantum confinement, such as quantum dots, nanoribbons, layered two-dimensional semiconductors, and hybrid perovskite nanostructures.
Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech), Artificial Intelligence (cs.AI), Computational Physics (physics.comp-ph), Quantum Physics (quant-ph)
Phase Formation and Thermal Stability of Superconducting Platinum Silicide Thin Films on Silicon
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Tharanga R. Nanayakkara, Ananya Chattaraj, Mingzhao Liu, Charles T. Black
Platinum silicide (PtSi) thin films are promising for silicon-based superconducting quantum devices due to their compatibility with CMOS fabrication, air stability, and superconducting transition temperature near 1 K. We report a systematic study of PtSi phase formation, microstructure, and interface quality as a function of annealing temperature and duration, characterizing films using grazing-incidence X-ray diffraction, X-ray reflectivity, and electrical transport measurements. Phase-pure PtSi forms within minutes by rapid thermal processing at 600 °C and is stable under extended annealing, while 30 s anneals across 300-600 °C yield equivalent film quality with consistent microstructure and superconducting properties. X-ray reflectivity reveals that interfacial roughening is an intrinsic consequence of the Pt2Si-to-PtSi conversion step rather than a result of elevated temperature or prolonged annealing. These results establish a robust processing window for PtSi formation in silicon-based superconducting device fabrication flows.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
6 pages, 8 figures. Supporting Information available as this http URL
Crystallizing Substrates Drag Supported Nanoparticles
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Cheng-Yu Chen, Duncan Burns, Peter W. Voorhees, Eric A. Stach
When a solid support undergoes crystallization, the advancing amorphous-to-crystalline transformation front separates regions of distinct surface energy, creating a moving interfacial energy boundary. A supported nanoparticle straddling such a boundary experiences an asymmetric particle-substrate interfacial energy environment that constitutes a lateral thermodynamic driving force for migration. Here, using in situ transmission electron microscopy to track Pt nanoparticle motion statistically, paired with time-resolved diffraction and 4D-STEM analysis to characterize support crystallization, we demonstrate that propagating crystallization fronts in amorphous AlO$ _x$ thin films actively drag supported Pt nanoparticles over long distances. Temporal correlation between the onsets of support crystallization and rapid particle migration, together with 4D-STEM virtual crystallinity maps, establishes that the front drives particle motion. Phase-field simulations confirm that particle-substrate interfacial energy contrast alone sustains particle drag, and identify curvature gradients along the particle surface as the mechanism by which the advancing front redistributes mass and displaces the particle. These results establish a general mechanism by which any propagating surface-energy boundary on a substrate can act as a deterministic driver of supported nanoparticle transport.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Elusive Exciton Insulator States in 1T-HfTe2: Exciton softening, and Symmetry Breaking by Ab Initio Methods
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Hong Tang, Niraj Pangeni, Daniel D. Rivera, Adrienn Ruzsinszky
Recent experiments have provided evidence for excitonic insulator (EI) states in 1T HfTe2. In this work, we investigate EI states in monolayer, bilayer, trilayer, and bulk 1T HfTe2 using advanced meta generalized gradient approximation (meta GGA) calculations and a model Bethe-Salpeter equation (BSE) approach, together with structural and electronic symmetry breaking analyses. Our results show that both the monolayer and bilayer exhibit negative exciton energies, leading to the spontaneous formation of bound excitons and EI states, whereas the trilayer and bulk display positive exciton energies and do not support EI states. Structural symmetry-breaking calculations show very small in-plane displacements of the Hf atoms from their symmetric positions in the monolayer and multilayers, consistent with experimental observations. Interestingly, electronic symmetry-breaking calculations for the monolayer, performed using a symmetric structure and a hybrid functional, show a pronounced unfolded valence-band feature at the M point and no unfolded conduction-band states near the Fermi level at Gamma, in good agreement with experimental results. Overall, our findings support the existence of EI states in low dimensional 1T HfTe2. The methodology developed here can be readily extended to investigate EI behavior in other related quantum material systems.
Materials Science (cond-mat.mtrl-sci)
14 pages , 2 Figures
Post Annealing Crystallization behavior of RF Sputtered Yttrium Iron Garnet thin films on Si/SiO2 patterned substrates
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Maria Roman, Tito Busani, Aleem Siddiqui
Yttrium Iron Garnet YIG (Y3Fe5O12), is a commonly used material for magnonic devices due to its crystal and chemical structure, which makes the material highly ferromagnetic and enables long-range magnon propagation. Magnonic devices were fabricated by depositing a 390 nm thick thin film of YIG, using low vacuum RF sputtering, on Si substrates with a 240 nm buffer layer of SiO2. Two sets of devices were used to study the effect of the Si/SiO2 interface on the YIG. The first set features patterned hole pairs on the SiO2, which was created using fluorine etching. Patterned samples were used as seed nucleation points to study the crystallization behavior. The second set was a non-patterned Si/SiO2 with YIG deposited uniformly on the top. Post-deposition recrystallization of the YIG film was accomplished in a horizontal furnace under O2 atmosphere, between 750 degrees C and 850 degrees C. By patterning devices with a SiO2 buffer layer, depositing YIG via RF sputtering, and subsequently crystallizing the films in a furnace, we establish a fabrication route toward devices that can be suspended. Although further optimization of stoichiometry is required, achieving precise compositional control would enable the realization of fully suspended and released YIG devices that can be transferred onto alternative substrates.
Materials Science (cond-mat.mtrl-sci)
Superconductivity in the high-pressure tetragonal phase of UTe2
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Yuhang Deng, Gabriel Mee, Tyler Wannamaker, Keke Feng, Mingyu Xu, Weiwei Xie, M. Brian Maple
Electrical transport and magnetic measurements have been made on UTe2 under pressure P up to approximately 16 GPa to determine the superconducting transition temperature Tc vs P phase diagram in the high-pressure tetragonal phase. Superconductivity emerges near 5 GPa, coincident with the orthorhombic to tetragonal phase transition; in the tetragonal phase, Tc reaches a maximum value of approximately 4 K at 6 GPa and then decreases with P and appears to vanish near 18 GPa. Tetragonal UTe2 has a relatively small upper critical field Hc2(0) $ \approx$ 1.2 T at 5.3 GPa, smaller than the Pauli paramagnetic limit, and is orbitally limited with a coherence length $ \xi$ tetra $ \approx$ 16.5 nm. This small value of Hc2(0) favors more conventional superconductivity; in contrast, the large values of Hc2(T) for orthorhombic UTe2 exceed the Pauli paramagnetic limit in all three crystallographic directions and have been attributed to unconventional superconductivity, widely believed to involve spin-triplet pairing. The temperature-pressure phase diagram of UTe2 shows a striking dichotomy: a narrow, fragile, unconventional superconducting region in the orthorhombic phase vs a broad, robust, and more conventional superconducting dome in the tetragonal phase. This dichotomy is consistent with the proposal that U-dimers, present (absent) in the orthorhombic (tetragonal) phase, may play a role in spin-triplet superconductivity of orthorhombic UTe2. In the tetragonal phase, the normal-state electrical resistivity $ \rho$ (T) exhibits metallic behavior with a knee between 200 and 240 K that depends weakly on P and most likely marks the onset of a transition to a magnetically ordered phase that coexists with superconductivity.
Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
Coherent control of chirality in Weyl semimetals
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Amar Bharti, Margarita Khokhlova, Misha Ivanov, Gopal Dixit
Weyl fermions in inversion-symmetric Weyl semimetals occur in pairs of opposite chirality, leading to symmetric optical responses under circularly-polarised light and a vanishing net photocurrent. Here, we show that tailored two-colour light fields break this symmetry and enable selective excitation of individual Weyl nodes. The interference between a circularly-polarised $ \omega$ field and a phase-locked linearly-polarised $ 2\omega$ field generates a chirality-dependent redistribution of carriers in momentum space, resulting in a nonzero controllable photocurrent. We demonstrate that both the magnitude and sign of the photocurrent can be tuned via the relative phase and field strength of the two colours, and identify an optimal regime in which chiral selectivity is maximised. Our results establish a general route to optically-controlled chiral charge dynamics in Weyl semimetals using polarisation-structured light.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Optics (physics.optics)
A Finite-Lattice Model from a Reciprocal Cost Action: Spectral and Reflection-Positivity Properties
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Jonathan Washburn, Megan Simons
We study the finite-lattice statistical-mechanical model whose nearest-neighbor bond potential is the reciprocal cost $ J(e^\varepsilon)=\cosh\varepsilon-1$ , selected by the d’Alembert functional equation under the stated regularity and calibration assumptions. The structural inputs are stated explicitly; once they are fixed, the analysis is rigorous mathematics about the bond action $ V(\Delta\phi)=\cosh(\Delta\phi)-1$ on finite boxes in $ \mathbb Z^3\times\mathbb Z/8\mathbb Z$ . Our main result pairs a negative and a positive statement about reflection positivity. For the continuous noncompact model the natural temporal kernel $ K(u)=\exp[-(\cosh u-1)]$ fails the Bochner positive-definiteness test: an interval-certified quadrature gives $ \widetilde K(3)<0$ . Thus the standard Bochner route to Osterwalder-Schrader reflection positivity is obstructed. For a finite-alphabet variant, with field values restricted to a finite symmetric set $ \Phi=v_0{-N,\ldots,N}$ , reflection positivity holds whenever the finite crossing-bond Toeplitz matrix $ (K_{\Phi(v_0,N)})_{a,b}:=K(b-a), a,b\in\Phi$ , is positive semidefinite. For $ v_0\in{1.2,1.5,2.5}$ , this is discharged by a rigorous diagonal-dominance certificate uniform in $ N$ , and the associated one-step transfer operator is then positive and self-adjoint in an explicit reflection-positivity inner product. These finite-volume results do not provide a continuum Wightman theory, Osterwalder-Schrader reconstruction, LSZ scattering, or a continuum mass gap.
Statistical Mechanics (cond-mat.stat-mech), Mathematical Physics (math-ph)
45 pages, 3 figures, no tables. Ancillary files include an 8-page supplementary PDF, Python verification scripts, saved numerical output, requirements file, and figure alternative text
Fragile electron-phonon superconductivity in MnB4 under pressure
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Renhai Wang, Shiya Chen, Feng Zheng, Zhen Zhang, Xingzhi Wang, Huafeng Dong, Cai-Zhuang Wang, Vladimir Antropov, Kai-Ming Ho, Yang Sun
The origin of pressure-induced superconductivity in MnB4 remains unclear. Here we show that it can be explained by electron-phonon coupling once the structural space is mapped using both volume and the Mn dimer distance as key structural parameters under compression. Minor changes in the dimer distance significantly affect electronic and phonon properties, bringing the calculated Tc into agreement with experiment. Our results suggest that MnB4 is a highly responsive system, providing a platform for probing the subtle interplay between structural instability, superconductivity and magnetism.
Superconductivity (cond-mat.supr-con), Materials Science (cond-mat.mtrl-sci)
Translationally Covariant Modulated Symmetries: Classification and Goldstone
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Bo-Ting Chen, Zihan Zhou, Biao Lian
Modulated symmetries are global symmetries with a spatially dependent unit of charge, such as the dipole symmetry and the exponential symmetry. We give the generic condition for a modulated symmetry to be compatible with translationally symmetric Hamiltonians, which we define as a translationally covariant modulated symmetry (TCMS). For Abelian TCMSs, we prove that their units of charge can only contain multipole, exponential and harmonic components. Particularly, we classify all the one-dimensional TCMSs by real Jordan normal form blocks. We further derive the generic Goldstone action for SSB phases of continuous TCMSs, by which we show that a broken multipole symmetry gives higher-order gapless Goldstone modes, a broken harmonic symmetry gives gapless Goldstone modes at finite momenta, and a broken exponential symmetry gives no gapless Goldstone modes, modifying the conventional Goldstone theorem.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas), Statistical Mechanics (cond-mat.stat-mech)
Wafer-scale Demonstration of High-voltage beta-Ga2O3 MOSFETs with Excellent Uniformity and over 3kV Breakdown Voltages
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Ningtao Liu, Hengrui Zhang, Shujun Zhu, Zhihao Yan, Dongyang Han, Shen Hu, Li Ji, Ning Xia, Jichun Ye, Wenrui Zhang
This study demonstrates a wafer-scale growth of a 2-inch Si-doped $ \beta$ -Ga2O3 (100) epitaxial wafer and the realization of uniform, high-voltage lateral $ \beta$ -Ga2O3 MOSFET arrays. The 2-inch homoepitaxial $ \beta$ -Ga2O3 (100) film grown by MOCVD exhibit excellent crystalline uniformity with an average rocking curve FWHM of ~27.0 arcsec and a low surface roughness less than 1 nm, alongside a uniform net doping concentration on the value of 4.60 $ \times$ 1E17 cm-3. The fabricated MOSFETs deliver a threshold voltage of -31.75 V, a drain-current on/off ratio over 1E9, a specific on-resistance of 126.52 mohm$ \cdot$ cm2 and breakdown voltage exceeding 3 kV. Statistical analysis across the entire wafer presents good device uniformity, with threshold voltages ranging from -28 V to -36 V, output current densities of 60-75 mA/mm, and a breakdown voltage over 3 kV. These results provide the demonstration using the 2-inch $ \beta$ -Ga2O3 epitaxial wafer to realize high-voltage $ \beta$ -Ga2O3 MOSFETs with wafer-scale performance uniformity for next-generation power device application.
Materials Science (cond-mat.mtrl-sci)
10 pages, 4 figures
Equilibrium spin currents in altermagnet junctions: Josephson-like and anomalous transport
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Altermagnets (AMs) offer a compelling platform for exploring novel spin-dependent phenomena in materials with zero net macroscopic magnetization. In this work, we theoretically investigate the emergence of equilibrium spin currents (ESCs) in two-dimensional AM heterostructures using a tight-binding lattice model. We first study an AM-normal metal-AM (AM-NM-AM) junction and demonstrate that the $ \sigma_y$ -polarized ESC exhibits a characteristic Josephson-like behavior, fundamentally governed by the relative angle ($ \theta$ ) between the Néel vectors of the two AMs pointing in $ xz$ -plane. Crucially, we show that replacing the central normal metal with a $ p$ -wave magnet (PM) induces an anomalous ESC. Analogous to the anomalous Josephson effect, the breaking of spatial inversion symmetry by the PM allows a finite, dissipationless spin current to flow even when the Néel vectors are perfectly aligned ($ \theta=0$ ). We establish that this anomalous transport is driven by an asymmetry in the quantum phases accumulated by right- and left-moving electrons undergoing spin-flip reflections. Finally, we show that the critical ESC exhibits pronounced fluctuations as a function of band filling, which we attribute to mesoscopic quantum size effects, including transverse subband quantization and longitudinal Fabry-Pérot resonances. Our findings highlight the potential of altermagnet junctions for designing dissipationless, phase-tunable spintronic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con)
5 pages, 5 captioned figures. Comments are welcome
Tracking metastable phases by complex Lee-Yang zeros
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Yi-Hua Dong, Ling Liu, Fang-Cheng Wang, Qi-Jun Ye, Xin-Zheng Li
Metastable phases (MPs) are energetically unfavorable states typically suppressed in equilibrium phase diagrams. Rather than remaining ‘’hidden’’, we show that they exist in the complex plane of thermal fields, as regions delineated by Lee-Yang zeros (LYZs). We demonstrate this numerically in a toy model with a tunable density of states featuring three Gaussian peaks and in a more realistic periodically driven system. In both cases, as artificial parameters or drive amplitudes increase, the LYZs bounding the MP approach the real axis and split into separated branches, signaling the emergence and stabilization of the MP within the enlarged gap between two adjacent stable phases. In the driven system, the imaginary part of LYZs correlates with drive strength, linking Lee-Yang theory to terahertz matter manipulation. These findings provide a scheme to describe MPs in phase diagram analysis. By viewing periodic drives as complex thermal fields, it also offers a new perspective for understanding and engineering non-equilibrium collective states.
Statistical Mechanics (cond-mat.stat-mech), Materials Science (cond-mat.mtrl-sci)
DC conductivity of tilted Dirac Fermions across the Lifshitz Transition: short- versus long-range impurities
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Mohammad H. Pakzamir (1), Zahra Faraei (1), Ali G. Moghaddam (2,3) ((1) Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan, Iran (2) Department of Applied Physics, Aalto University, Espoo, Finland (3) Computational Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, Finland)
We theoretically investigate the DC conductivity of two-dimensional tilted Dirac systems subject to short- and long-range impurity scattering. Using the Kubo formalism, we systematically study transport across the subcritical (Type I), critical, and overcritical (Type II) tilt regimes. In the subcritical phase, short-range impurities yield a frequency-independent conductivity that decreases monotonically with tilt. Conversely, long-range Coulomb scattering results in a strongly energy-dependent conductivity governed by a tilt-independent scattering rate. At the Lifshitz transition ($ t = 1$ ), the transport signatures of these impurities diverge fundamentally: the van Hove singularity in the density of states induces a localized conductivity dip for short-range disorder, but a pronounced macroscopic peak for Coulomb impurities. In the overcritical regime, an ultraviolet momentum cutoff is required to regularize the open Fermi surface, leading to distinct behaviors for each impurity type. Notably, the conductivity perpendicular to the tilt direction ($ \sigma_{xx}$ ) exhibits a cutoff-dependent, non-monotonic peak near $ t = \sqrt{2}$ for short-range defects, while it decays monotonically with increasing tilt for long-range scattering. For both potentials, the conductivity along the tilt axis ($ \sigma_{yy}$ ) increases without bound, revealing extreme transport anisotropy. For long-range impurities, the energy dependence of the conductivity becomes nearly quadratic and linear for Type I and II, respectively. Furthermore, vertex corrections vanish identically at the Lifshitz transition for both impurity types. Finally, we provide a unified geometric framework for these phenomena, establishing the tilt parameter as a powerful knob for engineering macroscopic transport in Dirac materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
17 pages, 10 figures
Non-magnetic ground state in A$_2$WCl$_6$ (A = Cs, Rb, K): A face-centered cubic system of spin-orbit-entangled $J$ = 2 states
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
T. Takayama, K. Ishii, S. Bette, J. Nuss, Y. Matsumoto, K. Fürsich, M. Minola, D. P. Sari, I. Watanabe, A. Krajewska, R. Dinnebier, B. Keimer, H. Takagi
Heavy transition metal compounds with strong spin-orbit coupling appeared as a platform for $ d$ -electron multipolar physics. We report the electronic, magnetic, and structural properties of antifluorite-type tungsten chloride A$ _2$ WCl$ _6$ (A = Cs, Rb, and K), comprising a face-centered cubic lattice of W$ ^{4+}$ ions. The 5$ d^2$ configuration of W$ ^{4+}$ ions in a cubic environment yields a spin-orbit-entangled $ J$ = 2 state, which has been discussed to give rise to multipolar ordering such as charge quadrupolar or magnetic octupolar ordering. We found that K$ _2$ WCl$ _6$ undergoes a cubic-to-tetragonal structural transition which lifts the degeneracy of the $ J$ = 2 state, leading to a non-magnetic singlet ground state. By contrast, Rb$ _2$ WCl$ _6$ and Cs$ _2$ WCl$ _6$ show no signs of phase transition and remain non-magnetic down to the lowest temperature measured. At low temperatures, signatures of weak structural anomalies were revealed, which may point to the presence of local distortions of the WCl$ _6$ octahedra. We argue that the subtle structural distortion arises from the local quadrupolar component of the $ J$ = 2 state but the frustrated quadrupolar interaction, together with chemical disorder, inhibits the formation of long-range quadrupolar ordering.
Strongly Correlated Electrons (cond-mat.str-el)
8 figures
Exact spectrum and anomalous relaxation in the open disorder-free Sachdev-Ye-Kitaev system
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Soshun Ozaki, Hironobu Yoshida, Hosho Katsura
We study a disorder-free variant of the Sachdev-Ye-Kitaev (SYK) model with dissipation within the Gorini-Kossakowski-Sudarshan-Lindblad formalism. By utilizing the integrability of the clean SYK model, we derive an exact solution in a spectrum-resolved form, i.e., the eigenvalues and corresponding projection superoperators of the Liouvillian for arbitrary system size $ N$ . We determine the scaling of the gap that governs the long-time decay of the two-point correlation functions. Importantly, the gap does not vanish in the dissipationless limit when the thermodynamic limit is taken first, despite the integrability of the model. This phenomenon, known as anomalous relaxation, suggests a possible connection with chaotic dynamics and quantum Ruelle-Pollicott resonances. We also find several spectral features, such as transitions in the Liouvillian spectrum from complex to real eigenvalues with increasing dissipation strength, as well as the convergence of the dissipative form factor to the spectral form factor in the dissipationless limit. These findings indicate that the present model offers a useful platform for exploring nontrivial open dynamics of many-body quantum systems.
Strongly Correlated Electrons (cond-mat.str-el), Statistical Mechanics (cond-mat.stat-mech), High Energy Physics - Theory (hep-th), Quantum Physics (quant-ph)
17 pages, 5 figures
Steering Selective Formation and 2D Crystallization of [4]Radialenes on Au(111) via [1+1+1+1] Cycloaddition of Isocyanides and Enantioselective Molecular Recognition
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Jian-Wei Liu, Ying Wang, Cui-Ping Wu, Jia-Xin Li, Li-Xia Kang, Jian-Hui Fu, Wen-Wen Gong, Pei-Nian Liu, Deng-Yuan Li
Conjugated carbon rings are fundamental skeletons of organic functional materials, and their selective formation is of paramount importance in molecular materials engineering. However, steering the formation and 2D crystallization of conjugated carbon rings on the surface with high chemo- and stereoselectivities remains a great challenge. Here, we report a highly chemoselective [1+1+1+1] cycloaddition of isocyanides on the Au(111) surface, which affords the stereospecific tetraaza[4]radialene products and further enables their long-range-ordered 2D crystallization via enantioselective molecular recognition. Using the progressive annealing method, we found that at room temperature, isocyanides undergo a coordination reaction with Au adatoms to form two-fold symmetric isocyanide-Au-isocyanide complexes. In contrast, gradually increasing the annealing temperature induces the transformation of these complexes and subsequent covalent polymerization, leading to the selective generation of tetraaza[4]radialenes with homotactic configurations. The tetraaza[4]radialenes further assemble into 2D homochiral molecular crystals through enantioselective molecular recognition driven by multiple C-H – Cl hydrogen-bonding interactions. By combining scanning tunneling microscopy/spectroscopy and non-contact atomic force microscopy, we determined the atomic structure and molecular orbitals of tetraaza[4]radialene, confirming that its four-membered ring adopts a planar geometry with a localized lowest unoccupied molecular orbital. Density functional theory calculations suggest that the [1+1+1+1] cycloaddition process involves stepwise formation of C-C bonds and its high selectivity arises from the spatial steric hindrance. Our findings provide new insights into the selective formation of conjugated rings on surfaces and have implications for engineering 2D homochiral molecular crystallization.
Materials Science (cond-mat.mtrl-sci), Chemical Physics (physics.chem-ph)
Inverse design of bespoke interatomic potentials via active learning by information-matching
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Yonatan Kurniawan (1), Logan D. Williams (2), Amit Samanta (2), Ilia Nikiforov (3), Daniel Schwalbe-Koda (4), Mark K. Transtrum (5), Ellad B. Tadmor (3), Vincenzo Lordi (2), Vasily V. Bulatov (2) ((1) Department of Physics and Astronomy, Brigham Young University, Provo, UT, USA, (2) Lawrence Livermore National Laboratory, Livermore, CA, USA, (3) Department of Aerospace Engineering and Mechanics, University of Minnesota, Minneapolis, MN, USA, (4) Department of Materials Science and Engineering, University of California, Los Angeles, CA, USA, (5) Cross Stream Consulting, Springville, UT, USA)
Interatomic potentials (IPs) enable large-scale atomistic simulations beyond the reach of first-principles methods, but their predictive reliability depends critically on the selection of training data, quantified uncertainty, and model expressiveness. Active learning (AL) provides a principled framework for constructing efficient and accurate IPs, yet most strategies reduce parameter uncertainty without explicitly accounting for the specific material properties being predicted. The information-matching (IM) approach addresses this limitation by requiring that the selected training data provide at least as much parameter space information as needed to achieve prescribed uncertainty targets for selected quantities of interest (QoIs). Here, we apply IM to develop bespoke IPs specifically tailored for predicting plastic strength in metals. Due to the high computational cost of simulating plastic strength, we employ an indirect IM strategy that targets inexpensive intermediate QoIs that correlate with strength. The IM method enables precise parameter constraints with minimal training data, yielding precise predictions for both the intermediate QoIs and plastic strength. Yet, model error remains a key limitation, and a post hoc uncertainty inflation correction provides a viable means to mitigate this limitation. These findings illustrate both the promise and limits of uncertainty-aware AL for predicting complex material properties.
Materials Science (cond-mat.mtrl-sci), Machine Learning (cs.LG)
The fluid-lattice gas isomorphism with application to liquid-vapor equilibrium in physisorbed monolayers
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Lev Shevchenko, Volodymyr Kulinskii
Liquid-gas equilibrium for a simple molecular fluid is considered in view of the existence of the order parameter, in terms of which the symmetry of the binodal is restored not only in the vicinity of the critical point (critical isomorphism) but also globally in the whole coexistence region. This leads to the mapping between fluid and lattice gas (Ising model). We test this approach against the data on the liquid-gas binodal of a two-dimensional Lennard-Jones fluid and monolayers of molecular fluids. The obtained results allow us to speculate about the analog of the Kramers-Wannier duality in such systems and provide the theoretical estimate for $ dp/dT$ on the saturation curve at the critical point. The microscopic grounds of the proposed approach are also discussed, and the transition from the continuous fluid model Hamiltonian to the effective quasi-spin lattice model is outlined.
Soft Condensed Matter (cond-mat.soft)
18 pages, 6 figures
Microscopic mechanism of high-temperature superconductivity revealed by ab initio studies on hole-doped multilayer cuprates HgBa$_2$Ca$_2$Cu$_3$O$_8$ under pressure
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Triple-layer cuprate superconductor $ \mathrm{HgBa_2Ca_2Cu_3O_8}$ (Hg1223) keeps the record of the highest superconducting (SC) critical temperature $ T_{c}\sim 134$ K among all the existing materials at ambient pressure. $ T_{c}$ further increases under pressure up to $ T_{c}\sim 160$ K. However, its microscopic mechanism remains to be elucidated. We solve {\it ab initio} Hamiltonians for Hg1223 using a variational solver supplemented by a neural network. The pressure dependence of the $ d$ -wave SC order parameter and estimated $ T_{c}$ show a dome-like structure in essential agreement with the experimental indications. The origin of the strong SC amplitude at ambient pressure is identified as strong local Coulomb repulsion $ U$ attributed to poor screening. Further increase in $ T_{c}$ under pressure is understood from interplay of three elements, namely increased electron hopping $ t$ , decreased $ U$ and more importantly, strongly reduced offsite Coulomb repulsion $ V$ with increasing pressure. Pairing mechanism is identified as the emergent local attraction counterintuitively generated from the originally strong local repulsion $ U$ . The emergent attraction is interpreted from attraction from reduced repulsion'', originating from the release of the fluctuating doubly-occupied sites characterized from the false vacuum’’ in the Mott insulator to the double-occupation-free $ d$ -wave SC states upon carrier doping. This instantaneous attraction is in contrast with the conventional BCS SC mediated by bosonic glues. The local attraction is consistent with the electron fractionalization supported in experimental analyses. The coexistence of the SC and antiferromagnetic order is also demonstrated as a characteristic feature of the multi-layer system. The microscopic understanding of Hg1223 offers a new route explicitly using this emergent attraction to design and optimize SC materials.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
23 pages, 28 figures
Correlated $\mathcal{PT}$-Symmetric Antiferromagnetic Topological Insulators with Giant Nonlinear Anomalous Thermoelectrics
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Heng-Yu Di, Zhen-Gang Zhu, Gang Su
Topological states in antiferromagnets (AFMs) offer a promising platform for exploring novel physical phenomena and advancing the applications of AFM spintronics. The AFM topological insulator (TI) state stands out as one of the most representative and prominent cases. Unlike the previously proposed AFM-TI states in noninteracting systems, here we employ an extended Kane-Mele-Hubbard model to demonstrate that electron correlations can give rise to a $ \mathcal{PT}$ -symmetric AFM-TI state. This state breaks both spatial inversion symmetry $ \mathcal{P}$ and time-reversal symmetry $ \mathcal{T}$ , and enables intrinsic topological nonlinear responses to dominate the leading-order dynamics of the system. The competition between electron correlations and spin-orbit coupling drives the system across a topological phase transition, where the closure of the bulk band gap induces singular behaviors in higher-order quantum geometric tensors. Such microscopic singular characteristics manifest macroscopically as pronounced enhancements in thermoelectric performance, charge conductivity, and thermal conductivity. These giant tunable transport signatures, which can be effectively modulated by mechanical strain and electrostatic gating, provide a feasible experimental route to probe and understand correlated topological materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Simultaneous nanoscale imaging of local conductivity and chemical potential in a quantum Hall isospin ferromagnet
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Jiawei Hu, Shiyu Zhu, Bohao Li, Yunhao Wang, Shuigang Xu, Zhihai Cheng, Chengmin Shen, Andre K. Geim, Fengcheng Wu, Hong-Jun Gao
Quantum Hall isospin ferromagnetism in multilayer graphene offers a versatile playground for exploring flat band correlated physics, driven by the intricate coupling of spin, valley, orbital, and layer degrees of freedom. However, a nanoscale probe capable of simultaneously mapping local conductivity and chemical potential in these exotic phases has yet to be realized. Here, we introduce scanning conductivity and chemical potential microscopy (SCCM), a technique integrating scanning microwave impedance microscopy and Kelvin probe force microscopy. We demonstrate SCCM by probing the quantum Hall states and many-body Landau level energy spectrum in bilayer graphene. Applied to marginally twisted double bilayer graphene, SCCM then reveals a cascade of quantum Hall isospin ferromagnetic states with unexpected re-emergence behaviors. Significantly, experimental many-body Landau level energy spectrum further uncovers the intricate connections of these complex phenomena to inter-subband Landau level crossings and Landau level single-particle wavefunctions. These insights enable the construction of a comprehensive quantum Hall phase diagram. Our results demonstrate SCCM’s capability in decoding complex quantum phenomena, establishing it as a versatile nanoscale probe for electron correlation and topology.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
Fidelity susceptibility and geometric response in flux-tuned Dirac systems: exact results from a low-energy two-level reduction
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
We study the parametric sensitivity of two-dimensional massive Dirac fermions subject to Aharonov-Bohm flux insertion, using the Bures metric (fidelity susceptibility) as the central statistical-mechanical response function. Near integer values of the reduced flux, the low-energy spectrum undergoes a flux-induced avoided crossing whose structure is controlled by the Dirac mass. Through a controlled low-energy projection of the full Dirac=Aharonov-Bohm operator onto an effective two-level subspace, valid near integer flux, we derive an exact closed-form expression for the ground-state Bures metric, which takes a universal Lorentzian profile centered at integer flux with width set by the mass parameter. The peak value scales as $ g^{\max}_{\lambda\lambda}\sim m^{-2}$ , diverging in the chiral limit in direct analogy with the divergence of thermodynamic susceptibilities near critical points. We introduce an integrated geometric susceptibility $ \chi(m) = \pi/(8m)$ , whose inverse-mass scaling is the information-geometric counterpart of power-law critical behavior, with the Dirac mass playing the role of a relevant coupling controlling the distance from the chiral fixed point. The Lorentzian profile is shown to arise from the curvature of the ground-state manifold on the Bloch sphere, requiring no dynamical input beyond the spectral structure. Importantly, this geometric response is independent of Berry curvature and topological invariants, emerging instead from a universal local spectral mechanism. Through its spectral representation, the Bures metric is identified as the geometric (paramagnetic) contribution to the persistent current susceptibility, encoding the sensitivity of persistent currents and orbital magnetization to flux variations and connecting information geometry to measurable response functions in mesoscopic Dirac systems.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Statistical Mechanics (cond-mat.stat-mech)
21 pages, 2 figures. To appear in Physica A
Nearly ballistic transport and high magnetic-field sensitivity in a $\text{Bi}_4\text{Br}_4$ topological Josephson weak link
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Superconducting weak links with high transparency offer an appealing approach for designing compact magnetic-field sensors, as their phase-dependent Andreev bound-state (ABS) spectrum produces a strong flux-to-signal response with minimal dissipation. One way to achieve ballistic transport in the weak link is to use the edge states of topological insulators, since these states resist backscattering and provide a unique path to developing topological insulator-based weak-link devices for highly efficient magnetic-field sensing. Building on this, we propose a weak-link device using superconducting Nb electrodes and a nanoribbon of $ \text{Bi}_4\text{Br}_4$ as the normal region, forming a Nb-1D (one-dimensional) $ \text{Bi}_4\text{Br}_4$ -Nb Josephson junction. We develop first-principles tight-binding Hamiltonians and orbital-resolved interface couplings in the Wannier basis, including spin-orbit coupling, based on density functional theory (DFT) calculations. The Eliashberg spectral function of bulk Nb, obtained via density functional perturbation theory (DFPT), indicates an electron-phonon coupling strength of 1.19 and a transition temperature of about 9 K, aligning well with conventional superconductivity in Nb. The subgap conductance is primarily influenced by Andreev processes. The ABS spectrum leads to a non-sinusoidal current-phase relation (CPR) with high forward skewness ($ +$ 1.74) and phase sensitivity to the magnetic field. Overall, our findings suggest that the Nb-1D $ \text{Bi}_4\text{Br}_4$ -Nb weak link is a promising platform for on-chip superconducting magnetic sensors, compatible with scalable nanofabrication and broader development of topological-superconductor hybrid electronics.
Superconductivity (cond-mat.supr-con)
20 Pages, 7 figures
Enhanced dumbbell diffusion in a periodic potential by the elevator effect
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
We present molecular dynamics simulations of the random walk of a dumbbell - two beads connected by a spring - in a one-dimensional periodic potential and compare our results in limiting cases to theoretical analytical equations. The relevant parameters in this system are the spring constant, the equilibrium distance of the spring (relative to the periodicity of the potential), and the amplitude of the potential. Dumbbells with equilibrium distances incommensurate with the potential periodicity and with a sufficiently large spring constant exhibit enhanced diffusion. The diffusion constant can exceed that of a single bead in the same potential landscape. In this case, the dumbbell resembles a traction elevator, with the two connected beads acting as the elevator car and counterweight: the ‘’elevator effect’’.
Statistical Mechanics (cond-mat.stat-mech)
6 pages, 6 figures
A spectral model of power-law decay in natural and engineered systems
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Balázs Sándor, Márk Honti, Henrique Santos Lima
We present a first-principles spectral mechanism for the emergence of nonextensive $ q$ -exponential dilution and power-law relaxation in non-ideal transport systems. By modeling an incompletely mixed reactor as a layered diffusion matrix with an absorbing boundary, we demonstrate that macroscopic power-law tails depend on the geometric interaction between the initial tracer placement and the domain’s boundary configuration. For a one-dimensional system, an asymmetric, volumetrically distributed initial concentration profile projects onto the low-wavenumber eigenmodes, generating an emergent Gamma distribution of relaxation rates; at an infinitesimal boundary layer thickness ($ \Delta z \to 0$ ), this profile yields the nonextensive $ q$ -exponential decay function exactly across the entire temporal domain with $ q = 5/3$ . Extended to $ d$ dimensions under a highly localized, boundary-adjacent singular initial condition, the resulting scaling exponents and corresponding $ q$ values depend explicitly on the spatial configuration of the absorbing boundaries. However, in the one-dimensional limit ($ d=1$ ), these distinct initial states and boundary formulations intersect, rendering the $ q=5/3$ exponent geometrically invariant. Our approach establishes a clear connection between linear diffusion transport and nonextensive statistical mechanics, showing how heavy-tailed transport can be derived from boundary geometry and spectral dimensionality.
Statistical Mechanics (cond-mat.stat-mech), Applied Physics (physics.app-ph), Classical Physics (physics.class-ph), Popular Physics (physics.pop-ph)
8 pages and 3 figures
Thermal Processing Limits in Oxide-Channel Ferroelectric Field Effect Transistors
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Lance Fernandes, Yu-Hsin Kuo, Chengyang Zhang, Priyankka Ravikumar, Ranie Jeyakumar, Dyutimoy Chakraborty, Jiayi Chen, Taeyoung Song, Kai Ni, Woohyun Hwang, Kwangyou Seo, Suhwan Lim, Wanki Kim, Daewon Ha, Julia Medvedeva, Suman Datta, Shimeng Yu, Asif Khan
In this work, we report a systematic study of the impact of high-temperature post-capping thermal annealing on the memory characteristics of Oxide-semiconductor channel ferroelectric field-effect transistors (OS-FeFETs). Using an identical engineered ferroelectric gate stack 8nm Hf0.5Zr0.5O2 (HZO) / 3 nm Al2O3 / 8 nm HZO (8/3/8) and a hybrid capping layer (3 nm HfO2 + 3 nm Al2O3), 10 percent Ga doped InO (IGO) channel and 4 percent W doped InO (IWO) channel FeFETs remain functional after annealing at temperatures up to 650 C for durations of up to 30 min and 10 min, respectively; further annealing results in irreversible loss of conduction and device failure. Detailed electrical analysis reveals that the MW enhancement originates from a preferential positive shift in the erased-state threshold voltage, while the programmed-state threshold voltage remains comparatively stable. Grazing-incidence X-ray diffraction measurements further indicate structural evolution in the IWO and IGO oxide channels with increasing annealing temperature, supporting the observed electrical trends.
Materials Science (cond-mat.mtrl-sci)
First-Principles Insights into Surface and Ligand Effects in Stoichiometric HgTe Quantum Dots
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Raagya Arora, Patrick J. Lohr, Dibyajyoti Ghosh, Jennifer Hollingsworth, Sergei Tretiak
HgTe quantum dots are promising mid-infrared nanomaterials owing to their exceptional bandgap tunability, yet their electronic structure is strongly influenced by surface coordination and ligand passivation at ultrasmall sizes. Here, we employ atomistic simulations to systematically investigate stoichiometric HgTe nanoclusters with sizes 0.86 to 1.85 nm. The in silico exploration uncovers a transition from confinement-dominated electronic structures with delocalized frontier states in small self-passivated clusters to surface influenced characteristics in larger nanoclusters. Increased coordination and bond-length inhomogeneity in the larger nanoclusters generate localized near-gap states centered on undercoordinated surface atoms. At intermediate sizes, the band edge states become spatially separated on different regions of the cluster without forming deep gap states, marking the onset of surface induced electronic asymmetry. In larger clusters (1.8 nm), common neutral ligands like amines, thiols, phosphines, and alcohols effectively eliminate surface-derived localized states by restoring local coordination and altering the band edge electronic structure through ligand surface hybridization. The sensitivity of the bandgap to ligand identity and binding site underscores the interplay between surface coordination and ligand chemistry in shaping the electronic structure of these nanoclusters. These insights provide an atomistic understanding of size-dependent electronic structures in ultrasmall HgTe clusters. The study further establishes neutral ligands as powerful chemical handles for engineering frontier electronic states relevant to infrared optoelectronic functionality.
Materials Science (cond-mat.mtrl-sci)
First-Principles Investigation of Electron–Phonon Coupling and Intrinsic Two-Gap Superconductivity in Hexagonal BAs3 Monolayer
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Jakkapat Seeyangnok, Udomsilp Pinsook
Two-dimensional superconductors with multiband electronic structures provide an ideal platform for exploring anisotropic and multigap superconductivity in the reduced-dimensionality limit. Here, we investigate the structural, electronic, vibrational, and superconducting properties of a hexagonal BAs$ _3$ monolayer using first-principles calculations combined with density functional perturbation theory and fully anisotropic Migdal–Eliashberg theory. The optimized structure is found to be dynamically and thermally stable, as confirmed by phonon calculations and ab initio molecular dynamics simulations. Electronic structure calculations reveal an intrinsic metallic state with multiple bands crossing the Fermi level and several disconnected Fermi-surface sheets derived primarily from hybridized B-$ p$ and As-$ p$ orbitals. The electron–phonon interaction is dominated by low-frequency As-derived phonon modes, yielding a total electron–phonon coupling constant of $ \lambda=0.75$ . Solving the anisotropic Eliashberg equations predicts a superconducting critical temperature of $ T_c=3.4$ K. The momentum-resolved superconducting gap exhibits a pronounced two-gap character with gap magnitudes of $ \Delta_1=0.75$ meV and $ \Delta_2=0.51$ meV at $ T=1$ K. The superconducting gaps remain finite over the entire Fermi surface, demonstrating a fully gapped nodeless superconducting state. Analysis of the momentum-dependent electron–phonon coupling reveals that the two-gap superconductivity originates from sheet-dependent pairing interactions associated with distinct Fermi-surface sheets. Our results establish monolayer BAs$ _3$ as an intrinsic anisotropic two-gap superconductor and expand the growing family of boron-based two-dimensional superconductors.
Superconductivity (cond-mat.supr-con)
14 pages, 6 figures
What Is a Pattern in Statistical Mechanics? Formalizing Structure and Patterns in One-Dimensional Spin Lattice Models with Computational Mechanics
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
This work formalizes the notions of structure and pattern for three distinct one-dimensional spin-lattice models (finite-range Ising, solid-on-solid, and three-body), using information-theoretic and computation-theoretic methods. We begin by presenting a novel derivation of the Boltzmann distribution for finite one-dimensional spin configurations embedded in infinite ones. We next recast this distribution as a stochastic process, thereby enabling us to analyze each spin-lattice model within the theory of computational mechanics. In this framework, the process’s structure is quantified by excess entropy (predictable information) and statistical complexity (stored information), and the process’s structure-generating mechanism is specified by its epsilon-machine. To assess compatibility with statistical mechanics, we compare the configurations jointly determined by the information measures and epsilon-machines to typical configurations drawn from the Boltzmann distribution, and we find agreement. We also include a self-contained primer on computational mechanics and provide code implementing the information measures and spin-model distributions.
Statistical Mechanics (cond-mat.stat-mech)
12 Figures. Published in Entropy
Entropy 2026, 28(1), 123
Topological bound states in the continuum with controllable multiplicity
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Bound states in the continuum (BICs) are spatially localized states embedded in the continuous spectrum without hybridizing with extended bulk modes. Recent advances in topological band theory have greatly enriched the understanding of BICs, which gives rise to boundary-localized topological BICs with extremely high robustness against disorders. However, there remains a challenge in realizing corner-localized topological BICs in a three-dimensional system due to the absence of both realistic theoretical models and effective topological characterization schemes. In particular, how to engineer a controllable number of corner-localized topological BIC is still an open question. Here, we propose that the corner-localized topological BICs can emerge in a class of generalized breathing pyrochlore lattice with general inter-cell hoppings. We further show that the number of BICs at each corner can be arbitrarily adjusted by changing the parameters of inter-cell hoppings. Remarkably, although these corner-localized topological BICs are intertwined with a substantial number of bulk modes, we can accurately characterize them through the polarized topological charges, which are nodal points with topological properties in Brillouin zone and are measurable in experiments. We also reveal three types of topological phase transitions of corner-localized BICs, which are associated with the different ways of closing the bulk energy gap and can be intuitively captured by the polarized topological charges. This work not only promotes the theoretical research of corner-localized topological BICs, but also opens an avenue for their experimental observation in the future.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
8+6 pages; 3+3 figures
Shear Banding in Amorphous Solids as a Nonlinear Screened Soft Mode Instability
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Yang Fu, Yuliang Jin, Avanish Kumar, Itamar Procaccia
Shear banding is a well-known and widespread instability in strained solids: under external strain, the deformation localizes along a line in two dimensions or a plane in three dimensions. Developing a proper theoretical description of this phenomenon is key to understanding mechanical failure in solid materials. Very recently, a nonlinear theory extending classical elasticity to include plastic deformations as topological charges was proposed, offering detailed predictions on the nature and consequences of the shear-banding instability. The theory derives a Hessian operator whose lowest eigenvalue vanishes at the onset of instability, and the corresponding critical eigenmode describes the displacement field across the shear band. The resulting soft mode possesses the selected localization scale and subsequently saturates into a finite-width shear band. The aim of this Letter is to examine this theory numerically, establishing the role of topological screening and nonlinear instability as the mechanisms governing shear banding during athermal quasistatic deformation. We show that the displacement profile around the shear band is directly determined by the screening parameter and the nonlinear coefficient, thereby quantitatively verifying the theoretical predictions. Our results demonstrate that shear banding differs fundamentally from fracture: it arises from a nonlinear instability of an elastic field screened by plastic deformations. This establishes topological screening as the essential mechanism governing shear banding in amorphous solids.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci), Statistical Mechanics (cond-mat.stat-mech)
7 pages, 9 figures
On the correlation lengths of confined spheres in a cylindrical pore
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
We investigate the structural correlations of hard spheres confined within a narrow cylindrical pore in the quasi-one-dimensional regime, where interactions are restricted to nearest neighbors. Using a Laplace-space formulation of the radial distribution function (RDF), we determine the correlation lengths and oscillation frequencies associated with its long-distance decay. In addition to the global RDF, we analyze transverse-resolved RDFs that account for the positions of particle pairs across the pore cross section. While these observables are associated with the same underlying pole spectrum, their residues depend on the transverse configuration and can vanish due to symmetry. As a result, different particle-pair configurations may be governed by different leading poles and display different correlation lengths and oscillation frequencies. In particular, the global RDF does not always reflect the longest-ranged correlations found in transverse-resolved observables. We examine how this behavior depends on density and confinement. In the strong-confinement limit, the system approaches the Tonks-gas behavior at finite pressure, and the differences between the RDFs disappear.
Soft Condensed Matter (cond-mat.soft)
10 pages, 7 figures
Dimensionality-Driven Charge Stabilization of Group-IV Color Centers in Diamond Ultrathin Films
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Jijun Huang, Bing Huang, Song Li
Neutral group-IV vacancy (XV, X = Si, Ge, Sn, and Pb) centers in diamond are emerging solid-state spin-photon interfaces because of their favorable spin coherence and inversion symmetry-protected optical transitions. However, stabilizing their neutral charge state typically requires stringent Fermi-level engineering in high purity boron-doped diamond, which poses significant materials-growth challenges. Here, we demonstrate that dimensional confinement in diamane provides an alternative route to charge-state stabilization without intentional doping. Using first-principles calculations, we show that quantum confinement and surface termination cooperatively tune the host band gap and shift the occupied defect states upward from the valence-band edge, thereby enlarging the thermodynamic stability window of the neutral charge state and suppressing valence-band assisted excitation pathways. We further reveal that the thickness and surface termination of diamane enable systematic tuning of the electronic structure, zero-field splitting, and spin-orbit coupling of XV centers while largely preserving their optical transition energies. Among the structures considered, hydrogenated diamane offers the most favorable balance between charge-state stability and magneto-optical performance. More broadly, our findings establish dimensional confinement as a general strategy for engineering the charge, optical, and spin properties of solid-state quantum defects.
Materials Science (cond-mat.mtrl-sci)
Microscopic universal theory of symmetry-enriched topological quantum spin liquids
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
An ultimate theory of a phase of matter should describe all its universal properties via quantities that are measurable numerically and experimentally. In this work, we present a microscopic universal theory of symmetry-enriched topological quantum spin liquids (TQSLs) in two spatial dimensions, which directly utilizes microscopically measurable quantities to describe the universal properties. This theory applies to generic TQSLs, which can be Abelian or non-Abelian, chiral or non-chiral. The symmetries are also general, which can include both internal and lattice symmetries, unitary and anti-unitary symmetries, and discrete and continuous symmetries. There can be spin-orbit coupling, the microscopic degrees of freedom may transform linearly or projectively under the symmetries, and the symmetries can permute anyons. The input of the theory is some microscopic states with anyons, operators that control the dynamics of anyons, and symmetry actions in the TQSL, and its output is a set of data characterizing the universal properties, whose underlying mathematical structure is a generalization of category theory. Based on this theory, we find an explicit bijective map between the universal data characterizing a TQSL with a symmetry described by a group $ G$ , where the symmetry actions may include both lattice and internal symmetries, and the corresponding universal data for a TQSL with only an internal symmetry group $ G$ , and thus establish a precise crystalline equivalence principle. We demonstrate our theory in symmetry-enriched TQSLs realized on quantum processors based on superconducting qubits, trapped ions, and Rydberg atoms, and in each example we verify the Lieb-Schultz-Mattis anomaly matching condition. Our theory provides a solid basis for identifying and manipulating symmetry-enriched TQSLs, which further paves the way for fault-tolerant quantum computation based on these systems.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Gases (cond-mat.quant-gas), High Energy Physics - Theory (hep-th), Mathematical Physics (math-ph), Quantum Physics (quant-ph)
36 pages + appendices + references
V-Doped Niobate Nanosheets for Enhanced Photocatalytic Activity
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
V-doped [Ca$ _{2}$ Nb$ _{3-x}$ V$ _{x}$ O$ _{10}$ ]$ ^{-}$ (x = 0, 0.15, 0.3, 0.6, 0.75) nanosheets were produced by solid state reaction followed by protonation and exfoliation by tetrabutylammonium ions. 2D nanosheets have improved photocatalytic activity due to their small thickness that reduces electron-hole recombination, larger surface area that increases photocatalytic sites, and decreased band gap from added V. V-doping has caused the wide band gap of 3.54 eV of undoped nanosheets to decrease to 2.60-2.88 eV range. 10 vol% methanol was used as a hole scavenger in the hydrogen evolution reactions, and 3 wt% Pt was deposited on nanosheets as a co-catalyst. Under a full-spectrum Xe light, [Ca$ _{2}$ Nb$ _{2.7}$ V$ _{0.3}$ O$ _{10}$ ]$ ^{-}$ has produced 4.7 times the H$ _{2}$ yield as undoped nanosheets with a 11.3 mmol/g/h production rate, [Ca$ _{2}$ Nb$ _{2.7}$ V$ _{0.3}$ O$ _{10}$ ]$ ^{-}$ with Pt co-catalyst has produced 2.9 times the H$ _{2}$ yield as undoped Pt-loaded nanosheets.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph)
Main Paper: 6 pages, 5 figures, 1 table. Supporting Information: 4 pages, 5 figures
Divergent Coherent Phonon Responses Across the Metal-Insulator Crossover
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Felix Hoff, Timo Veslin, Tim Bartsch, Carl-Friedrich Schön, Dante M. Kennes, Matthias Wuttig
Ultrafast laser control of material properties hinges on understanding light-matter interactions. We use two experimentally accessible response functions, laser fluence induced phonon softening and the amplitude of coherent reflectance oscillations, to compare how strongly different materials respond to ultrafast photoexcitation. Comparing a diverse set of materials, we find that only a narrow class, including Sb, GeTe, and Bi2Te3, shows exceptional responses such as pronounced phonon softening and a giant increase of reflectance oscillations with increasing fluence. These response functions peak in an intermediate conductivity regime of about 102 - 104 S/cm, at the crossover between localized and delocalized electronic states. The corresponding class of solids also shows other unconventional properties including high dielectric constants, enhanced Born effective charges, coordination numbers exceeding the 8-N rule and uncommon bond rupture. This suggests that these materials employ a unique bonding mechanism, coined metavalent bonding. Frozen-phonon DFT calculations show that the strong fluence dependence arises from Peierls-like instabilities, leading to large deformation potentials and anharmonic double-well potentials. These findings identify metavalent bonding as a design principle for enhanced coherent phonon control and provide a quantitative framework for identifying materials with exceptional ultrafast responses.
Materials Science (cond-mat.mtrl-sci)
Inhomogeneous Coulomb Models Without Defects are Sick: Domain Wall Energies Scaling as Volume (not Boundary Area)
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
In this work we show that coulomb models, ones that obey a $ \nabla\cdot\left\langle \mathbf{B}\right\rangle =0$ divergence free constraint - for $ \left\langle \mathbf{B}\right\rangle $ being some coarse grained variables related to the microscopic degrees of freedom of the lattice system - are sick without the inclusion of defects with $ \nabla\cdot\mathbf{B}\neq0$ . We show that for generic boundaries (ones where the fluxes of the pseudo-magnetic fields on the boundary do not cancel: $ \left(\left\langle \mathbf{B}{R}\right\rangle -\left\langle \mathbf{B}{L}\right\rangle \right)\cdot\mathbf{n}\neq0$ - here $ \mathbf{n}$ is the unit normal and $ \left\langle \mathbf{B}{R/L}\right\rangle $ are the two ground state pseudo-magnetic fields on either side of the domain wall) without the inclusion of defects, sharp domain walls (on the order of the width of a unit cell) between different phases of the system cost energy proportional to system size (not boundary area). We present several different examples of this phenomena in the square lattice six vertex model, in quantum dimers and in classical spin ice in the presence of magnetic fields. We also show by example that the condition $ \left(\left\langle \mathbf{B}{R}\right\rangle -\left\langle \mathbf{B}{L}\right\rangle \right)\cdot\mathbf{n}=0$ is a necessary but not sufficient condition for the boundaries to be compatible - that is domain wall energy to scale with domain wall area and not system size. To further present the importance of boundary conditions in Coulomb systems we show that system boundaries, even ones that satisfy $ \int{\partial V}\mathbf{B}\cdot\mathbf{n}=0$ , have thermodynamic consequences - that is there is a cost, extensive in system size, to the Helmholtz free energy.
Strongly Correlated Electrons (cond-mat.str-el)
Comments are welcome
Novel 2D Altermagnetic Vanadium Oxide with a Buckled Lieb Structure
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Tamer Taşkıran, Soheil Ershadrad, Biplab Sanyal, Cüneyt Şahin
Altermagnetism has recently emerged as a highly promising phase for spintronics, offering the combined advantages of both antiferromagnets and ferromagnets. Here, using a first-principles analysis based on density functional theory (DFT), we identify a monolayer V$ _2$ O crystal in a buckled Lieb lattice as a promising two-dimensional altermagnetic material. The structural and thermal stability of V$ 2$ O is verified through calculations of the crystal’s formation energy, phonon structure, room-temperature ab initio molecular dynamics, and stiffness matrix. The system is found to exhibit auxetic behavior with a negative Poisson’s ratio. Our calculations indicate an antiferromagnetic ground state with a local magnetic moment of $ 2.79,\mu{\mathrm{B}}$ per V atom and a magnetocrystalline anisotropy that favors an out-of-plane easy axis. The electronic structure exhibits a momentum-dependent spin splitting of 1.2 eV, which is a characteristic of altermagnets. Inclusion of spin-orbit coupling breaks the symmetry of the quadratic band crossing near the Fermi level, resulting in a large Berry curvature and significant intrinsic spin Hall conductivity around $ 40,(\hbar/e),\mathrm{S,cm^{-1}}$ . The results demonstrate that monolayer V$ _2$ O serves as a robust room-temperature altermagnetic platform, exhibiting magnetic anisotropy and spin-dependent transport responses.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
Nonperturbative isotope effect on light-matter interaction in boron arsenide
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
The interaction of light and matter under strong isotope disorder gives rise to unconventional physics that goes beyond the quantum perturbation theory. In boron arsenide, the large mass difference between the two stable boron isotopes presents a paradigmatic case where perturbation theory fails, yet a unified theoretical framework across the perturbative and nonperturbative regime has remained elusive. Here, we develop a nonperturbative approach to capture isotope-disorder effect in boron arsenide, which fundamentally alters light-matter interactions. We reveal that coherently mixed vibrations between two boron isotopes reshape the dielectric function in the nonperturbative regime. The nonperturbative isotope interactions dictate the properties of coupled surface phonon polaritons and near-field radiative heat transfer. Two-fold tuning of radiative heat flux is achieved by modulating the surface phonon polariton resonance via isotope engineering. This work establishes a unified framework connecting the perturbative and nonperturbative limits, enabling quantitative predictions across weak to strong disorder regime.
Materials Science (cond-mat.mtrl-sci)
Phys. Rev. B 113, 134316 (2026)
Coexistence of High Temperature Superconductivity and Antiferromagnetic Order in a Cuprate with Multiple Hole Fermi Pockets
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Xiangyu Luo, Yinghao Li, Hao Chen, Yiwen Chen, Jumin Shi, Taimin Miao, Bo Liang, Wenpei Zhu, Neng Cai, Xiaolin Ren, Yingjie Shu, Chaohui Yin, Jiuxiang Zhang, Chengtian Lin, Shenjin Zhang, Zhimin Wang, Fengfeng Zhang, Feng Yang, Qinjun Peng, Zuyan Xu, Guodong Liu, Xintong Li, Hanqing Mao, Tao Xiang, Lin Zhao, X. J. Zhou
The intricate relationship between high temperature superconductivity and antiferromagnetic order in cuprates, and the fundamental origin of electron pairing remain open questions. By utilizing high-resolution laser-based spatially-resolved angle-resolved photoemission spectroscopy, we investigate the seven-layer $ Bi_{2}Sr_{2}Ca_{6}Cu_{7}O_{18+\delta}$ (Bi2267) and identify a cuprate system that consists of multiple hole Fermi pockets. The observed Fermi pockets exhibit pronounced momentum-, temperature- and Fermi surface-dependent energy gaps. Crucially, high temperature superconductivity with a critical temperature ($ T_{\mathrm{c}}$ ) of $ \sim$ 75 K emerges in a system with multiple Fermi pockets and the presence of strong antiferromagnetic order and correlations. In particular, substantial electron pairing is observed along the Fermi pocket with an energy gap up to $ \sim$ 42 meV in lightly-doped CuO$ _{2}$ planes ($ p\sim$ 0.05). These findings challenge the conventional understanding of the roles of the nodal and antinodal electronic states in driving high-temperature superconductivity. They show that superconductivity and antiferromagnetism can coexist in a cuprate with multiple Fermi pockets, offering further insights into the pairing mechanism in cuprate superconductors.
Superconductivity (cond-mat.supr-con), Strongly Correlated Electrons (cond-mat.str-el)
Information Entropy Based Crystal Structure Prediction of Chemically Disordered Alloys via Graph Convolutional Neural Networks
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
The phase prediction of chemically disordered alloys poses a significant computational challenge due to the combinatorial complexity of such materials. The high-throughput compositional exploration of chemically disordered alloys, including high-entropy alloys, requires an approach to efficiently explore the potential energy landscape of such complex materials. Additionally, a metric to quantify the potential energy landscape explored for phase prediction of the compositions needs to be defined. We propose an information-theoretic approach to phase prediction in chemically disordered alloys in the present work. We demonstrate the applicability of alchemical Monte Carlo sampling using an efficient Graph Convolutional Neural Network-Based machine learning model. We additionally demonstrate the applicability and limitations of the Bond Disproportion Vector (BDV) as a low-computational-cost descriptor and benchmark it against the state-of-the-art Smooth Overlap of Atomic Positions (SOAP) descriptor. We show the applicability of an information entropy-based metric for the phase prediction of binary (CoNi, MoW, FeNi and TaW), ternary (CoCrNi, CrFeNi), quaternary (CoCrFeNi) and quinary ($ \mathrm{Al_x(CoCrFeNi)_{1-x}}$ ) alloys. Information entropy-based phase prediction can be applicable in challenging cases where conventional approaches are not feasible.
Materials Science (cond-mat.mtrl-sci)
Dynamical cavity method for continuous-time complex systems on sparse random graphs
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-09 20:00 EDT
Fernando L. Metz, Isaac Pérez Castillo
Dynamical mean-field theory (DMFT) reduces dense high-dimensional disordered dynamics to a self-consistent effective stochastic process. For sparse and heterogeneous networks, however, local fields contain finitely many strong inputs, so the Gaussian closure mechanisms of dense DMFT need not apply. We develop a continuous-time cavity derivation of sparse-network DMFT at the level of path measures for stochastic dynamics with general pairwise interactions on sparse random graphs. The cavity equations are exact on trees and yield the finite-time thermodynamic description on locally tree-like graphs. They show explicitly how reciprocity changes dynamical closure: fully directed graphs recover the sparse directed path-probability equation, whereas reciprocal or bidirected edges require conditional path kernels driven by the imposed history of the receiving node. Ensemble averaging gives laws over path-probability messages, with barycenters and higher-message moments closing by multilinearity and independence of incoming branches. A causal discrete-time derivation yields the corresponding population-dynamics representation, distinguishing trajectory populations for directed graphs from conditional branch-law or finite-depth tree populations for reciprocal graphs. We also formulate finite-memory numerical closures and test them in an additive-input recurrent neural network specialization. Finally, high-connectivity limits are obtained as projections of the sparse path-measure theory, clarifying when dense drift, noise, and response channels reduce to standard low-dimensional DMFT and when path-level descriptions remain essential.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
Discovering and decoding latent mean-field structure with variational autoencoders
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Marco Biroli, Max Welling, Vincenzo Vitelli
Generative models are increasingly used to capture correlations in many-body systems, but the representations they learn remain largely opaque to physical interpretation. Here, we establish an intuitive criterion that quantifies the capacity of a variational autoencoder (VAE) to faithfully reconstruct the joint probability distribution of a many body system. In a nutshell, a bound on the VAE capacity is obtained by comparing the rate of the latent channel to the bipartite mutual information of the data. Using this bound, we show that the conditionally independent decoder of any successful VAE is structurally identical to a finite-size mean-field factorization. Hence, a successful reconstruction is direct evidence for a latent mean-field theory and the microscopic parameters of that theory can be read off the trained decoder. We validate these conclusions on a hierarchy of solvable models with scalar (Curie-Weiss), vector (Hopfield) and tensor (Maier-Saupe) order parameters, recovering the full Hopfield pattern matrix from equilibrium samples alone. We find that, when applied to Salamander retinal recordings, a two-latent VAE reproduces the population statistics with only two effective collective variables allowing us to recover the `stored patterns’ of the neural population and write a generalized Hopfield model which correctly models the experimental data.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech), Machine Learning (cs.LG)
10 pages, 5 figures
Statistical Mechanics of Random Matrices
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-09 20:00 EDT
These lecture notes are based on the lectures on \emph{Statistical Mechanics of Random Matrices} delivered at the Spring College on the Physics of Complex Systems, held at the Abdus Salam International Centre for Theoretical Physics, Trieste, Italy, from 19 February to 15 March 2024. Their aim is to present a statistical-mechanics route to the spectral theory of sparse and diluted random matrices, with emphasis on cavity and replica methods, resolvent techniques, population dynamics, typical spectral densities, spectral-count fluctuations and large deviations, conditioned spectra, and non-Hermitian extensions. The written form of the notes has been deliberately expanded beyond the material actually covered during the lectures. This is partly because a set of lecture notes can afford a more systematic development than a sequence of blackboard lectures, and partly because several natural continuations of the material become clearer once the central methods have been introduced. Consequently, not every topic discussed here was presented during the College. The additional material is included to give a more coherent account of the subject and to indicate directions that, hopefully, can be covered in greater detail in future lectures or schools. Since these are lecture notes rather than a state-of-the-art review, the choice of topics is necessarily selective and is naturally tilted towards the author’s own work and collaborations on this subject. I have nevertheless tried, within the limits of this format, to place the material in contact with the broader literature and to represent the surrounding state of the art as fairly as possible. Inevitably, some relevant contributions may be missing or treated too briefly; such omissions are unintentional and reflect the pedagogical scope of the notes rather than a judgement on their importance.
Disordered Systems and Neural Networks (cond-mat.dis-nn)
Ultracold Amplification Proposal for Parity Violation in Chiral Molecules
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-09 20:00 EDT
Daniel Martínez-Gil, Pedro Bargueño, Salvador Miret-Artés
We propose a theoretical mechanism to indirectly detect the small parity-violating energy difference (PVED) between chiral enantiomers through a macroscopic enantiomeric excess observed in an ultracold gas. We consider that chiral molecules are formed resonantly via ultracold collisions of achiral diatomic molecules, with PVED inducing a slight asymmetry in the resonance energies of right- and left-handed configurations. After formation, chiral molecules evolve within a Bose-Einstein condensate (BEC), incorporating nonlinear interactions, tunneling between enantiomeric states, intrinsic PVED, and thermal conversion rates. These collective dynamics enable amplification of the microscopic bias into a global population imbalance. Using coupled rate equations, we show that, under realistic regimes, a complete enantiomeric excess can be achieved even for extremely small intrinsic asymmetries. We illustrate the model with concrete examples (HSOH, H$ _2$ Se$ _2$ , H$ _2$ Te$ _2$ ), predicting observable enantiomeric excesses under plausible experimental conditions. We also consider non-PVED effects that could be amplified under the proposed mechanism, including electric and magnetic fields as well as thermal fluctuations, the latter being illustrated through the aforementioned molecular examples. Overall, our results suggest that ultracold physics could provide a new pathway to probe molecular parity violation, a fundamental weak effect that remains experimentally undetected.
Quantum Gases (cond-mat.quant-gas), Quantum Physics (quant-ph)
Wave Resistance for Stochastic Motion at Interfaces
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Maxence Arutkin, Shlomi Reuveni, Elie Raphael
Wave resistance is the drag generated by the wave radiation that a source moving at a fluid interface sustains. Under stochastic trajectories, the mean drag is controlled by the ensemble-averaged surface profile built from the trajectory history. We show that the result is a finite resistance below the deterministic radiation threshold and a regularization of the singular response at the minimum phase velocity of the capillary-gravity waves. We derive explicit scaling laws for drifted Brownian trajectories, including a universal high-diffusivity decay. For drifted Lévy flight, we find the mean wave resistance in closed-form, extending wave-drag theory to non-Gaussian trajectories.
Statistical Mechanics (cond-mat.stat-mech), Fluid Dynamics (physics.flu-dyn)
4 pages, 4 figures
Chiral-Angle-Controlled Altermagnetic Spin Splitting in Nanotubes
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Ersoy Sasioglu, Tom. G. Saunderson, Börge Göbel, Ingrid Mertig, Samir Lounis
Altermagnets exhibit momentum-dependent spin splitting despite having zero net magnetization. Here, we show that rolling a two-dimensional (2D) $ d$ -wave altermagnet into a nanotube transforms this momentum-dependent spin splitting into chiral-angle-controlled one-dimensional (1D) spin splitting through dimensional projection. Using a minimal tight-binding model and first-principles calculations, we demonstrate that the nanotube spin splitting follows a characteristic $ \cos(2\theta)$ dependence, vanishing for nodal orientations and reaching extrema for antinodal orientations. The mechanism remains robust across a broad class of nanotubes derived from 2D altermagnets. Our results establish dimensional projection as a general route for transferring momentum-dependent altermagnetic spin splitting into 1D systems and provide a framework for engineering spin-split quantum states in low-dimensional magnetic materials.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 pages, 3 figures
Energy Barriers for Reversible Chain Scission and Healing under Tension with Displacement Control
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Mohammad A. Ansari, Kenneth M. Liechti, Dmitrii E. Makarov, Rui Huang
Polymer chain scission is a key mechanism for fracture of soft materials. It is well known from single-molecule force spectroscopy experiments that the critical condition for chain scission depends on the loading rate and other environmental effects (e.g., temperature and solvent). Common approaches to describing the kinetics of chain scission often assume force-controlled conditions, that is, when a polymer chain is stretched by a prescribed force. As a result of this assumption, chain scission is irreversible, excluding the possibility of healing. In many soft materials, however, self-healing has been observed after fracture, suggesting possibly reversible chain scission. Here, we show that reversible chain scission is possible under displacement-controlled conditions, that is, when a polymer chain is stretched with a prescribed end-to-end distance. We present a breakable freely-jointed chain model, assuming that a polymer chain breaks when one of its links breaks while the other links remain nearly rigid. At a prescribed end-to-end distance, the free energy of the chain has two local minima and a local maximum (the transition state), giving rise to energy barriers for chain scission and healing. As the prescribed displacement increases, the energy barrier decreases for scission but increases for healing, depending on the chain length (number of links) and the potential energy of the link. With the energy barriers, we adopt a kinetic approach to predict the statistics and kinetics of a single polymer chain under tension, first by integrating the rate equation and then by kinetic Monte Carlo simulations. Notably, the present model predicts rate-dependent chain scission, with a lower bound for the rupture force that could be several orders of magnitude lower than the upper bound (which is close to the theoretical strength of the covalent bonds).
Soft Condensed Matter (cond-mat.soft)
Under review
Fluctuation-stable generalized entropy probes of spectral heterogeneity
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Generalized entropy measures are widely used to characterize localization and multifractality, and the regime (q>1) is often empirically found to exhibit improved numerical stability and cleaner scaling behavior. Here, we develop a fluctuation-stability framework for generalized entropy diagnostics and show that weak-amplitude spectral fluctuations are amplified for (q<1) and suppressed for (q>1), thereby providing a theoretical basis for the physically robust (q>1) regime. A thermodynamic scaling analysis further identifies an asymptotically stable regime beyond a critical threshold. As an application, we introduce the entropy-gradient susceptibility (\chi_q) as a coarse-grained probe of spectral heterogeneity. Using the Aubry-André and generalized Aubry-André models, we demonstrate that (\chi_q) sharply distinguishes homogeneous localization transitions from mobility-edge coexistence regimes. Our results establish fluctuation stability as a guiding principle for generalized entropy diagnostics in quasiperiodic systems.
Statistical Mechanics (cond-mat.stat-mech)
9 pages, 3 figures
Predictable Mean-Field Chaos in Random Recurrent Networks
New Submission | Disordered Systems and Neural Networks (cond-mat.dis-nn) | 2026-06-09 20:00 EDT
Alkesh Yadav, Vladimir Shaidurov, Jonathan Kadmon
Dynamical mean-field theory recasts deterministic chaos in random recurrent networks as an effective stochastic process. We show that for analytic nonlinearities with sufficiently fast Fourier decay, this stochasticity is only apparent: the continuous past of a realized mean-field trajectory uniquely determines its future. The mean-field theory is therefore not merely an ensemble description, but a conditional prediction theory for individual trajectories. Unfolding the power spectrum into a Krylov state space exposes how this latent determinism is organized across an infinite hierarchy of temporal modes. The associated Krylov growth rate sets the complexity of finite-resolution prediction and upper-bounds the largest Lyapunov exponent in this class of networks. Thus, microscopic sensitivity and predictive complexity are distinct aspects of mean-field chaos. Our results extend Krylov growth ideas developed for Hamiltonian chaotic dynamics to classical dissipative systems.
Disordered Systems and Neural Networks (cond-mat.dis-nn), Neurons and Cognition (q-bio.NC)
5 pages, 2 figures, Supplementary material
Chiral Surface Phonons
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
We use symmetry arguments combined with density functional theory to demonstrate that all surfaces of crystalline materials host surface phonons that are chiral. As model system, we study slabs of highly symmetric AB rocksalt compounds, and find surface-localized phonons whose atomic displacements exhibit chiral motion. We further show that these chiral surface phonons generate sheets of in-plane magnetism at the surface. Our results reveal that chiral phonons can emerge in all crystalline materials as a result of reduced symmetry at surfaces or interfaces. These findings establish surfaces as a previously overlooked source of chiral phonons and their associated magnetic moments, which could play a role in a broad range of surface-sensitive measurements.
Materials Science (cond-mat.mtrl-sci)
6 pages, 5 figures
Time Evolution of Heat Conduction in a Generalized Model of Brownian Motion
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
We investigate the properties of heat conduction in a network of harmonic oscillators interacting with heat baths, described by a generalized model of Brownian motion. This model includes noise and dissipation terms in both the momentum and position equations. This generalization is motivated by the requirement of consistency with the Gorini-Kossakowski-Sudarshan-Lindblad (GKSL) equation. Because standard definitions of heat current based on velocity become mathematically inconsistent in this framework, we derive an analytical expression for the steady-state heat flow based on an extended framework of stochastic energetics. We confirm that Fourier’s law (linear thermal response) is satisfied and that the model naturally captures microscopic thermal boundary resistance, analogous to Kapitza resistance. This demonstrates that our generalized model functions as a valid phenomenological framework for simulating non-equilibrium processes, marking a crucial step toward a unified formulation of stochastic and quantum thermodynamics. Furthermore, we analyze the time evolution of heat conduction by numerically solving the corresponding differential equations for the correlation functions. Unlike standard Brownian motion, the generalized model generates continuous and nowhere differentiable trajectories for both momentum and position (as is characteristic of overdamped dynamics). Finally, we show that the heat current exhibits characteristic transient behavior when the inter-particle interaction is switched on. Specifically, an instantaneous heat flow emerges, whose direction is strictly governed by whether the interaction is attractive or repulsive, significantly differing from the predictions of the standard model.
Statistical Mechanics (cond-mat.stat-mech), Nuclear Theory (nucl-th), Quantum Physics (quant-ph)
17 pages, 16 figures
Topological invariant responsible for the integer QHE and non-commutative geometry
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
G. Kovyrshin, A. Mekrami, J. Miller, M.A. Zubkov, A. Zuevsky
We consider a wide class of $ 2D$ tight - binding models of solid state physics. These models are, in the most general case, non - homogeneous. The topological invariant $ {\cal N}_3$ responsible for the quantization of the Hall conductivity, for the specific case of the integer quantum Hall effect in $ 2D$ , is expressed through the Wigner transformation of the two-point electron Matsubara Green function. We express this invariant as a pairing of the element of the $ K^{-1}$ group (generated by the Green function) with the specific element of the cyclic cohomology group $ HC^3$ . According to a set of local index theorems the values of $ {\cal N}_3$ can be shown to be integer for a limited class of tight - binding models.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Latex, 53 pages, 1 figure
Local electronic structure and dynamics of hydrogen in $\text{CeO}_2$
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
A. Koda, T. U. Ito, M. Hiraishi, H. Okabe, R. Kadono
The local electronic states of muon (Mu) as an isotope of hydrogen (H) in high-quality single-crystalline ceria (CeO$ _2$ ) are investigated using muon spin rotation/relaxation ($ \mu\text{SR}$ ) and first-principles density functional theory (DFT) calculations. Upon positive muon implantation, both paramagnetic (Mu$ ^0$ ) and diamagnetic (Mu$ ^\ast$ ) states are observed below $ \approx$ 10 K. Magnetic field dependence of the Mu$ ^0$ signals combined with DFT results provides evidence for the formation of a polaron state, consisting of Mu bonded to a ligand oxygen and a $ 4f$ electron localized on a nearby Ce site. The crystal-orientation dependence of the Mu$ ^0$ signal suggests strong anisotropy of the $ 4f$ electron due to the spin-orbit coupling with lifted degeneracy. Furthermore, the Mu$ ^0$ state exhibits transition to the Mu$ ^\ast$ state that corresponds to another Mu$ ^0$ state (exhibiting a diamagnetic response due to fast spin/charge fluctuations) at temperatures above $ \approx$ 10 K, before disappearing above $ \approx$ 30 K. These findings suggest rapid diffusive motion of the $ 4f$ electrons and/or Mu (as well as H) at higher temperatures.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 5 figures, with supplemental material
Chemical tuning of magnetic ordering and cryogenic magnetocaloric response in zircon-type Gd1-xErxVO4
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Ming Zeng, Muqing Su, Liang Ming, Xiaolong Yang, Wang Chen, Lingwei Li, Hai-Feng Li
Chemical substitution offers an effective route to tune magnetic ordering and magnetocaloric performance in rare-earth oxides for cryogenic refrigeration. Here we investigate the structural evo lution, magnetic properties, and magnetocaloric effect of polycrystalline zircon-type Gd1-xErxVO4 (x=0, 0.1, 0.25, 0.5, and 0.75). Powder X-ray diffraction confirms that all samples crystallize in the tetragonal zircon structure without detectable impurity phases. Substitution of Gd3+ by the smaller Er3+ ion produces a systematic lattice contraction and modifies the magnetic behavior of the rare-earth sublattice. In particular, the magnetic ordering temperature is suppressed from 3.65(2) K in GdVO4 to 2.76(2) K in Gd0.9Er0.1VO4 , accompanied by a weakening of the spin-flop-like field-induced anomaly observed in the parent compound. A low Er concentration correspondingly improves the low-temperature magnetocaloric performance, with Gd0.9Er0.1VO4 exhibiting a max imum magnetic entropy change of 45.1 J kg-1 K-1 for mu_0 Delta H=7T. These results demonstrate that weak Er substitution effectively tunes the competition among exchange interactions, dipolar coupling, and magnetic anisotropy, optimizing the balance between magnetic ordering and available spin entropy in zircon-type rare-earth vanadates, which is crucial for developing efficient cryogenic refrigeration materials.
Materials Science (cond-mat.mtrl-sci), Applied Physics (physics.app-ph), Quantum Physics (quant-ph)
11 pages, 8 figures
Valley Engineering in Bilayer WSe$_2$ Gate-All-Around Transistors
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Katsunori Wakabayashi, Souren Adhikary, Kazuhito Tsukagoshi
In bilayer WSe$ 2$ , interlayer coupling reduces the K–$ \Gamma$ valley splitting to $ \Delta{K\Gamma} \approx k_BT$ at room temperature, placing two hole-transport channels of markedly different effective mass in near-thermal equilibrium. We combine density functional theory (DFT) with spin–orbit coupling and an analytical two-valley device model to quantify how this near-degeneracy governs hole transport in gate-all-around (GAA) field-effect transistors. Three main results are obtained: (i)the subthreshold swing is protected near $ 60$ ~mVdec$ ^{-1}$ by quantum-capacitance screening independently of layer number; (ii)the effective mobility is set by the K-to-$ \Gamma$ valley occupation ratio and decreases monotonically with layer number; and (iii)in the bilayer, compressive biaxial strain \emph{simultaneously} enhances the on-current, suppresses the off-current, and improves the on/off ratio from $ {\approx}69$ to $ {\approx}156$ , while the subthreshold swing remains near the thermionic limit. This decoupling of on-state performance from switching slope is inaccessible through conventional mobility engineering and establishes a concrete design principle: \emph{valley-engineering sensitivity is maximized when $ \Delta_{K\Gamma} \approx k_BT$ }, the condition most naturally satisfied by bilayer WSe$ _2$ at room temperature and zero strain, making it the optimal channel for valley-engineered GAA transistors.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
12 pages, 7 figures
Superconducting diode effect in magnetic superconductors realized by nonreciprocal domain-wall dynamics
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
Dong Hui Han, Suk Bum Chung, Se Kwon Kim
A superconducting diode effect is shown to arise in ferromagnetic superconductors through the nonreciprocal dynamics of magnetic domain walls. Specifically, we show that current-driven dynamics of a magnetic domain wall under a certain external field can exhibit a nonreciprocal Walker breakdown, possessing two distinct direction-dependent critical currents beyond which the domain wall precesses continuously. In ferromagnetic superconductors, the constant rotation of a domain wall is shown to give rise to phase slips, opening up dissipation channels, whereby the nonreciprocal Walker breakdown is mapped to the superconducting diode effect. For the nonreciprocal Walker breakdown of a magnetic domain wall, we analytically examine its dependence on the magnetic field and the Gilbert damping and verify the theoretical results with micromagnetic simulations. We then extend the analysis to ferromagnetic superconductors by considering additional effects from the superconductivity and identify criteria for experimental conditions to realize the predicted superconducting diode effect. Our work demonstrates that topological defects, such as domain walls, in magnetic superconductors can serve as an intrinsic nanoscale platform for nonlinear nonreciprocal superconducting functionalities within a single homogeneous material, circumventing the need for complicated engineered heterostructures and thereby enabling the miniaturization of superconducting devices down to the nanometer scale that is challenging to achieve with conventional Josephson junctions.
Superconductivity (cond-mat.supr-con), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Precipitate phase selection and grain boundary morphology in Cu-Ni-Si-Mn alloys: A machine-learning interatomic potential study
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Aadil Fayaz Wani, Il-Seok Jeong, Haekwan Jeon, Jaesun Kim, SuDong Park, Eun-Ae Choi, Seung Zeon Han, Seungwu Han, Byungki Ryu
Alloys inevitably contain interphase boundaries, whose energetics govern nucleation processes and precipitate morphology. In Cu-Ni-Si alloys, Mn addition markedly changes grain boundary (GB) precipitation behavior. While GB precipitation of stable Ni$ _2$ Si in Mn-free alloys is associated with degraded mechanical properties, Mn addition instead promotes film-shaped Mn$ _6$ Ni$ _{16}$ Si$ _7$ (G-phase) precipitation, which is correlated improved mechanical properties. However, the atomic origin of the contrasting GB phase selection and morphology remains unclear. Here we perform machine-learning interatomic potential (MLIP) calculations to investigate the effect of interphase-boundary atomic structure on GB precipitates in Cu-Ni-Si alloys with and without Mn. The MLIP calculations reliably reproduce DFT-level energetics for interfacial bonding and microstructural configurations, and further predict that Mn addition favors GB precipitation of Mn$ _6$ Ni$ _{16}$ Si$ _7$ rather than Ni$ _2$ Si. Experimentally, Mn-free alloys are observed to exhibit irregularly-shaped Ni$ _2$ Si precipitates with open-boundary-like Cu/Ni$ _2$ Si interfaces, whereas Mn-added alloys exhibit film-like G-phase at GBs. Large-scale atomistic interface calculations reveal that the coherent interface structure between Cu and Ni$ _2$ Si favors the formation of plate-like strained Ni$ _2$ Si precipitates in the matrix. Upon coarsening and stress release, an out-of-phase coherent-like interface can form at GBs, generating a local repulsive region that gives rise to surface-like open-boundary structures and explains the irregular morphology of GB stable Ni$ _2$ Si precipitates. In contrast, Cu/Mn$ _6$ Ni$ _{16}$ Si$ _7$ interfaces remain predominantly incoherent with moderate boundary energies and no pronounced repulsive regime, thereby stabilizing continuous interfacial contact and explaining film-shaped GB precipitation.
Materials Science (cond-mat.mtrl-sci)
45 pages, 3 tables, 9 figures, 61 references, 3 SM tables, 2 SM figures
Dynamic scaling and Family-Vicsek universality in the Hubbard model at infinite temperature
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Cătălin Paşcu Moca, Doru Sticlet, Balázs Dóra
We study Family-Vicsek scaling of charge, spin, and energy fluctuations in the one-dimensional Hubbard model at infinite temperature. Using a quantum generating function approach, we compute time-dependent cumulants of transferred conserved quantities and analyze how the corresponding roughness depends on subsystem size and time. We start by focusing on a single interface at half the chain and determine the transport exponents. Then we turn to fluctuations of a small finite interval and study the Family-Vicsek universality of fluctuations over an extended timescale. We find that the long-time scaling behavior is controlled by integrability. In the free limit, charge, spin, and energy all display ballistic transport. In the interacting integrable Hubbard chain, charge and spin cross over to a KPZ scaling regime, while the energy sector remains ballistic. Once integrability is broken by a next-nearest-neighbor density interaction, the long-time dynamics becomes diffusive in all sectors. In every case we also observe a short-time microscopic regime with apparently universal ballistic growth before the hydrodynamic scaling window sets in. The Family-Vicsek setup allows us to determine the growth, the saturation as well as the dynamical exponents.
Strongly Correlated Electrons (cond-mat.str-el), Quantum Physics (quant-ph)
11 pages, 6 figures
Symmetry-Breaking Induced Spin Transport and Magneto-Optical Regulation in 2D Altermagnet Ru2MoSe4
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Wenpeng Wang, Hang Shi, Yuping Tian, Wei-Jiang Gong, Xiangru Kong
Two-dimensional (2D) altermagnets (AMs) offer a compelling paradigm for advanced spintronics, yet their fully compensated macroscopic spin currents inherently limit practical device integration. In this work, using first-principles calculations and theoretical analysis, we demonstrate that the 2D material Ru2MoSe4 hosts AM ground state protected by S4zT symmetry. Using uniaxial strain modulation and stacking configuration, we show that the monolayer and the AC-stacking bilayer Ru2MoSe4 host fully spin-polarized currents, piezomagnetically induced net magnetization, and the magneto-optical Kerr effect. Our findings establish Ru2MoSe4 as a tunable platform, offering a feasible mechanism to simultaneously trigger electrical spin transport signals and amplify optical readout signatures for next-generation spintronics and valleytronics.
Materials Science (cond-mat.mtrl-sci)
Molecular dynamic simulation of multicomponent CoCrFeNiMn high-entropy alloy thin film deposition
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Oleksandr I. Kushnerov, Sergey I. Ryabtsev, Valerij F. Bashev
The deposition and growth of a thin CoCrFeMnNi high-entropy alloy film on an Al(100) substrate were investigated by molecular dynamics simulation. Interatomic interactions were described using a calibrated set of Morse potentials combined with mixing rules for regular solutions. During a 100 ns simulation, 50,000 atoms with an incident energy of 10 eV were deposited, producing a film of about 6.1 nm thickness. The resulting film contains face-centred cubic (FCC), body-centred cubic (BCC), hexagonal close-packed (HCP), and amorphous regions. Analysis of the radial distribution function (RDF) was used to determine nearest-neighbour distances and estimate lattice parameters for the crystalline phases. The simulated phase composition and structural parameters are in good agreement with available experimental data.
Materials Science (cond-mat.mtrl-sci)
Accepted manuscript. 12 pages, 5 figures. Published in Molecular Crystals and Liquid Crystals 769(7-8) (2025), 762-772. DOI: https://doi.org/10.1080/15421406.2025.2504044
Mol. Cryst. Liq. Cryst. 769(7-8) (2025) 762-772
Artificial Intelligence for Instability in Inorganic Perovskites: From Mechanism Discovery to Engineering Strategies
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Xue Zhao, Chuan-Xin Cui, Zi-Hao Xu, Yuan-Long Pang, Jun-Jie Li, Jin-Wu Jiang
Three-dimensional all-inorganic halide perovskites, represented by CsPbX$ _3$ (X = Cl, Br, I), have attracted broad interest in photovoltaics, photodetectors, and light-emitting devices because of their outstanding optoelectronic properties. Their practical deployment, however, remains limited by instability under thermal, chemical, optical, and electrical stress. Conventional studies have established important experimental and theoretical foundations, but they still struggle with multimodal data, coupled degradation pathways, protocol dependence, sparse statistics, and uncertainty quantification. Artificial intelligence (AI) offers a practical route to address these limitations. This review summarizes recent progress in AI-assisted studies of instability in 3D CsPbX$ _3$ and organizes the discussion around four linked tasks, including stability discrimination and diagnosis, microscopic mechanism analysis, consequence and reliability modeling, and engineering stability enhancement. We further discuss the main limitations of current methods, especially in data quality, protocol consistency, benchmark design, interpretability, and transferability across domains. Finally, we outline future directions for the field, including standardized data infrastructures, interpretable cross-scale models, and tighter integration of AI with automated experiments and physics-based modeling. The aim of this review is to provide a coherent and practically useful framework for researchers seeking to use AI to understand, predict, and mitigate instability in inorganic perovskites.
Materials Science (cond-mat.mtrl-sci)
6 figures
Designing electronic magnetoelectric matter with organic quantum spin trimers
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Yuko Hosokoshi, Christopher P. Aoyama, Zhuowei Zhang, Toshio Ono, Kosuke Takada, Ayaka Higashiguchi, Seitaro Iisaka, Koudai Yamasaki, Hironori Yamaguchi, Shengzhi Zhang, Mohammad Irfan, Minseong Lee, Eun Sang Choi, Yasuyuki Shimura, Toshiro Sakakibara, Zhiyuan Xie, Hiroki Nakano, Yasu Takano, Cristian D. Batista, Yoshitomo Kamiya
Magnetoelectric (ME) phenomena are commonly driven by spin-lattice coupling. Here we demonstrate a different route based on frustrated quantum spin trimers that intrinsically intertwine magnetic moments and electric dipoles. Using molecular design principles, we realize a weakly coupled lattice of equilateral $ S=1/2$ spin trimers in the organic radical crystal TNN$ \cdot$ CH$ _3$ CN. In this material, correlated electronic fluctuations within each trimer generate electric dipoles, while geometrically frustrated intertrimer interactions organize them into collective ME states. Magnetization, thermodynamic, and dielectric measurements reveal multiple magnetic-field-induced phases, including the $ 1/3$ -magnetization plateau marked by pronounced dielectric anomalies. Effective low-energy theories and numerical simulations show that these phenomena are driven by electronically generated trimer dipoles whose collective order is stabilized by frustration relief of the intertrimer interactions, establishing a direct connection between geometric frustration and emergent magnetoelectricity. Our results identify quantum spin trimers as multifunctional building blocks, providing a bottom-up route for designing correlated ME materials from electronically active quantum spin clusters.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
13 pages, 6 figures; Supplementary Information included
BSE+ calculations for 2D materials: a unified description of excitons and plasmons
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Amalie H. Svaneborg, and Kristian S. Thygesen
The Bethe-Salpeter equation (BSE) accurately describes low-energy optical spectra in materials with strong excitonic effects, but its high computational cost limits the number of electron-hole transitions that can be included. Neglecting high-energy transitions leads to an underestimation of the real part of the dielectric function, often producing a spurious plasmon peak in the BSE electron energy loss spectrum (EELS). The recently introduced BSE+ method addresses this by combining a four-point BSE-like equation for the irreducible polarisability with a two-point Dyson equation that includes the high-energy transitions at the Random Phase Approximation (RPA) level. Here, we present a detailed account of the method, extend it to two-dimensional materials, and apply it to a set of transition metal dichalcogenide monolayers. BSE+ preserves the excitonic features of the BSE at low energies while reproducing the plasmonic structure of the RPA at higher energies, yielding good agreement with experimental EELS data across the full energy range and strongly suppressing the spurious plasmon. BSE+ converges much faster than BSE with respect to the electron-hole basis size, at a comparable computational cost, and is implemented in the GPAW code.
Materials Science (cond-mat.mtrl-sci)
8 pages, 3 figures
Quantitative measurement of fluid inertial effects in confined Brownian motion
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Quentin Ferreira, Pablo Palacios-Alonso, Harshit Joshi, Rafael Delgado-Buscalioni, Yacine Amarouchene, Thomas Salez (LOMA, X)
The hydrodynamic response of Brownian particles in liquids is fundamentally altered by inertial forces arising from unsteady momentum transport in the surrounding fluid. These forces are of two distinct types,: the added mass and the history effect. While both are well understood in bulk and weakly-confined geometries, under deterministic driving, their respective behaviours under strong confinement and thermal fluctuations remain scarcely addressed, unclear and often entangled together. The goal of the present study is thus to fill this fundamental gap. The behaviours of the two distinct inertial contributions are quantitatively investigated in the vicinity of a flat, rigid wall, using a combination of broadrange thermal colloidal-probe atomic-force-microscopy experiments, advanced numerical simulations and theory. The separation of the added-mass and history-force contributions is achieved through their different frequency-scaling signatures within the measured high-resolution thermal spectra. Our results establish a complete picture of Brownian motion at interfaces, in the lubrication regime, with direct relevance to nanofluidics and interfacial biophysics.
Soft Condensed Matter (cond-mat.soft), Statistical Mechanics (cond-mat.stat-mech), Classical Physics (physics.class-ph), Fluid Dynamics (physics.flu-dyn)
Metal Halide Perovskite/Chalcohalide Heterojunctions for the Photoinduced Oxidative Coupling of p-substituted Thiophenols
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Anna Cabona, Stefano Toso, Alejandro Cortés-Villena, Ignacio Rosa-Pardo, Mirko Prato, Michele Ferri, Julia Perez-Prieto, Ilka Kriegel, Liberato Manna, Raquel E. Galian
The introduction of a semiconductor-semiconductor junction is an effective strategy to enhance the photocatalytic performance of perovskite nanocrystal-based systems. Herein, we optimized the synthesis of CsPbX3/Pb4S3X2 (X= Cl, Br, I) perovskites-chalcohalides heterostructures, whose band alignment can be tuned by halide composition. As a proof-of-concept, we evaluated the photooxidative coupling of p-substituted thiophenols at room temperature, under visible-light, air, and without sacrificial electron donor. Notably, CsPbBr3/Pb4S3Br2 achieved up to 94 % selectivity toward disulfide (p-OCH3 thiophenol with a turnover number of 14300) highlighting the crucial role of the type-II heterojunction to promote charge separation and efficient electron delocalization across the junction.
Materials Science (cond-mat.mtrl-sci)
55 pages, 35 figures
ACS Applied Nano Materials 2026 9 (11), 4841-4847
Order parameters and ground-state phase diagram of the interacting topological Su-Schrieffer-Heeger model with extended-range hoppings
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Tsz Hin Hui, Pedro D. Sacramento, Wing Chi Yu
Topological insulators have attracted numerous attentions recent years, where the Su-Schrieffer-Heeger (SSH) model is one of the most studied models. While the interacting version of it has been explored recently, the interplay between interactions and long-range hoppings merit further investigations. In this work, we uncover a rich phase diagram of the interacting SSH model with extended-range hoppings, in which it consists of several topological phases, two novel superconducting-like (SC-like) phases and five distinct charge-density-wave (CDW) phases. We substantiate that the SC-like and two CDW phases are direct consequences of imbalanced interactions and extended-range hoppings. We derive the order parameters (OPs) for each of the phases and verify them in large-system simulations, finding consistency with the entanglement entropy and the fidelity in capturing the phase transitions. In contrast to the non-interacting case where the favored hoppings are unidirectional in the topological phases, the derived OPs suggest non-unidirectional hoppings are possible under the influence of interactions.
Strongly Correlated Electrons (cond-mat.str-el), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Superconductivity (cond-mat.supr-con), Quantum Physics (quant-ph)
17 pages, 8 figures
Evaluation of nonlinear optical coefficients in uniformly aligned dioxane-based ferroelectric nematic liquid crystals using second harmonic generation
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Hirokazu Kamifuji, Jigen Furukawa, Kazuma Nakajima, Hirotsugu Kikuchi, Kenjiro Fukuda, Masanori Ozaki
Ferroelectric nematic liquid crystals (FNLCs) are promising soft platforms for nonlinear optics, but quantitative determination of their second-order nonlinear optical coefficients has been hindered by limited alignment control. Here, polarization-resolved second-harmonic generation (SHG) measurements on a uniformly aligned dioxane-based FNLC, combined with Jones-matrix simulations, enable determination of all principal tensor components. The resulting tensor is consistent with the expected $ C_{\infty v}$ and Kleinman symmetries, while the measured coefficients cannot be explained by a simple sum of molecular first hyperpolarizabilities. These results provide a quantitative basis for understanding nonlinear optical responses and guiding the design of FNLC-based nonlinear optical materials and devices.
Soft Condensed Matter (cond-mat.soft)
Main text: 11 pages, 6 figures; Supplementary information: 5 pages, 6 figures
Strain-Induced Tuning of Third-Harmonic Generation in Monolayer Black Phosphorene
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Yan Meng, Kainan Chang, Wei Song, Yuwei Shan, Jin Luo Cheng, Luxia Wang
Based on the tight-binding model and the semiconductor Bloch equations, this work systematically reveals the microscopic mechanism of strain engineering in turning of third-harmonic generation (THG) in monolayer black phosphorene (BP). %
The results show that under strain-free conditions, monolayer BP exhibits significant in-plane anisotropy, and its dominant susceptibility component reaches a maximum of $ \chi^{(3);xxxx} = 1.8 \times 10^{-17} , \text{m}^2/\text{V}^2$ , agreeing well with the experimental results. %
By applying uniaxial and biaxial strains along the armchair ($ x$ ), zigzag ($ y$ ), and out-of-plane ($ z$ ) directions, we find that the THG response presents strong direction dependence and unique spectral shifting behaviors: in-plane compressive strain and out-of-plane tensile strain both significantly enhance the THG conductivity and induce a redshift, whereas in-plane tensile strain and out-of-plane compression lead to suppression and a blueshift, with the tuning efficiency following the order of $ z > y > x$ . The microscopic origin of these phenomena is identified as the synergistic modulation of the bandgap and Berry connection by strain. %
Furthermore, the synergistic or competitive effects of biaxial strain further enrich the manipulation of THG signals. %
Strain engineering can serve as an effective strategy for dynamically controlling nonlinear optical processes in two-dimensional materials, and it also lays a theoretical foundation for the development of high-performance reconfigurable infrared photonic devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Correlation enhanced resistance hysteresis near half filling in MoS2/WSe2 heterobilayer
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Yong Chen, Weikang Zhang, Meizhen Huang, Shengling Xiang, Zishu Zhou, Yaqi Ma, Chenxuan Lou, Haoxi Ji, Aoqian Zhang, Yifei Jin, Liheng An, Zefei Wu, Chun Cheng, Ning Wang
Ferroelectricity, typically arising from ionic displacements in noncentrosymmetric lattices, enabling applications in memory devices and sensors. Recent advances in two-dimensional materials and van der Waals heterostructures have revealed novel ferroelectric phenomena, including sliding ferroelectricity and correlation-driven ferroelectricity in moire superlattices. In this work, we fabricate and study a MoS2/WSe2 moire superlattice device exhibiting a high field-effect mobility of 17,650 $ cm^2V^{-1}s^{-1}$ . Electrical transport measurements reveal correlated insulating states accompanied by a prominent and reproducible resistance hysteresis near half filling. Temperature and displacement field dependence further confirms the correlation-enhanced nature of the hysteresis. Our analysis suggests that displacement field-induced metal-to-insulator transition at correlated insulating state coupled with interfacial dipoles enables the observed resistance hysteresis. These results establish correlation enhanced resistance hysteresis near half filling in a MoS2/WSe2 heterobilayer, offering opportunities for exploring emergent quantum phases and device functionalities.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
accepted in Chinese Physics Letters
The impact of interfacial chemistry on the band offset of GaAs/Ga$_2$O$_3$ heterostructures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Sofia Apergi, Alfredo Pasquarello, Charles Cornet, Laurent Pedesseau
Ga$ _2$ O$ _3$ /GaAs heterojunctions are emerging as promising candidates for next-generation power electronics, photonics, and energy devices, leveraging the high breakdown voltage and thermal stability of Ga$ _2$ O$ _3$ alongside the mature technology, high hole mobility, and higher refractive index of GaAs. The efficiency of these devices depends strongly on the band alignment between the two materials, however both type-I and type-II alignment have been reported in the literature for these heterostructures. To address this ambiguity, we use hybrid density functional theory to systematically investigate the band alignment at GaAs/Ga$ _2$ O$ _3$ interfaces, focusing on the role of interface chemistry. By considering Ga-O-, As-, and As-O-rich interfaces both in amorphous and crystalline Ga$ _2$ O$ _3$ phases, we demonstrate that interface stoichiometry determines the alignment type: Ga-O-rich interfaces exhibit type-II alignment with large valence band offsets (3.1 eV), while As-rich and As-O-rich interfaces favor type-I alignment with reduced offsets (2.3-2.6 eV). These trends are attributed to interface dipole formation driven by bonding configuration. Our findings provide insight into the relationship between chemistry and band alignment in GaAs/Ga$ _2$ O$ _3$ heterostructures, enabling targeted optimization for specific device applications.
Materials Science (cond-mat.mtrl-sci)
Curvature-guided topology and self-assembly in chiral nematics and liquid-crystal colloids
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Ivan I. Smalyukh, Mykola Tasinkevych
In soft condensed matter, curvature does more than simply distort an ordered medium: it helps select defect structures, redistribute elastic stress, bias chirality, and guide self-assembly. This review examines how curved, multiply connected, and knotted boundaries in liquid-crystal colloids and confined nematics generate topological defects and localized solitonic textures, and how these structures mediate interactions between mesoscale building blocks. We introduce a unifying framework based on genus, Euler characteristic, anchoring, and chirality, and use it to discuss spherical, handlebody, and boundary-bearing colloids, together with droplets and polymer-dispersed nematics of nontrivial topology. Particular emphasis is placed on the interplay of geometry and topology in determining boojums, disclination loops, hedgehog charges, and linked and knotted defect structures. We then turn to chiral systems hosting skyrmions, torons, hopfions, and related localized textures, highlighting how chirality and confinement stabilize three-dimensional topological states. Finally, we discuss how these concepts translate into design principles for controlled self-assembly, templating, and functional composite materials. More broadly, we argue that liquid-crystal colloids and confined nematics provide experimentally accessible model systems in which curvature, topology, and chirality can be harnessed as programmable tools for designing organized soft matter.
Soft Condensed Matter (cond-mat.soft), Materials Science (cond-mat.mtrl-sci)
43 pages, 24 figures
Non-Bloch band theory of boundary-controlled magnon edge modes in an antiferromagnetic chain
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Suman Debnath, Sonu Verma, Rohit Mukherjee, Arijit Kundu
We define a winding number within the Non-Bloch band theory framework that captures the emergence of magnon edge modes in a one-dimensional antiferromagnetic spin chain, even when the conventional Bloch winding number is trivial. Within linear spin-wave theory, magnon excitations are governed by a non-Hermitian dynamic matrix, despite the underlying Hamiltonian being Hermitian. The symmetry classification of this matrix yields a trivial bulk invariant, however, finite systems exhibit boundary-localized modes, signaling a breakdown of the conventional bulk-boundary correspondence. We further show that these edge modes can be controlled via boundary perturbations. By tuning the boundary potential, the modes can be driven into or out of the bulk spectrum. To resolve the bulk-boundary mismatch, we develop a non-Bloch framework based on a generalized Brillouin zone and a winding number that correctly predicts the presence of edge states. Our results establish boundary-controlled topological transitions that are experimentally accessible through local Zeeman fields or modified edge anisotropy in antiferromagnetic van der Waals nanostructures.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
12 pages. Comments welcome
Layer-parity-defined surface polarization in Nb$_3$Cl$_8$ for excitonic modulation at van der Waals interfaces
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Xinyue Huang, Hansheng Xu, Yuchen Gao, Yushen Zhou, Zhijie Ma, Kenji Watanabe, Takashi Taniguchi, Zuxin Chen, Jianqi Huang, Jianpeng Liu, Teng Yang, Youguo Shi, Yu Ye
The intrinsic symmetry breaking in the breathing kagome lattice of layered Nb$ _3$ Cl$ _8$ provides a unique mechanism for realizing electrically polar surfaces. In each monolayer, the trimerization of Nb atoms breaks inversion and mirror symmetries, generating an out-of-plane electric dipole. The AB-stacked $ \alpha$ phase arranges adjacent layer dipoles antiferroelectrically, leaving the uncompensated surface polarization strictly governed by layer parity. Here, using atomic force microscopy operated in Kelvin probe force microscopy mode, we directly visualize layer-dependent polarization states in exfoliated Nb$ _3$ Cl$ _8$ flakes and resolve a pronounced odd-even oscillation of the surface electrostatic potential. Beyond this parity-locked antiferroelectric order, we further identify intralayer polar domains in which local atomic reconstructions of the breathing kagome network reverse the out-of-plane dipole of the surface layer, producing ferroelectric-like stacking configurations. By interfacing monolayer MoSe$ _2$ with Nb$ _3$ Cl$ _8$ , we demonstrate that these surface-polarization textures effectively modulate adjacent excitonic emission through domain-dependent interfacial band alignment and charge transfer. Our findings establish Nb$ _3$ Cl$ _8$ as an intrinsic layer-polarized van der Waals platform and show that layer parity provides powerful structural degree of freedom for programming excitonic and optoelectronic responses at van der Waals interfaces.
Materials Science (cond-mat.mtrl-sci), Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
9 pages, 4 figures
Unconventional incommensurate epitaxy of superconducting FeSe films on SrTiO$_3$
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
M. Klement, K. M. Fijalkowski, M. Kamp, C. Gould, L. W. Molenkamp
We present a combined X-ray diffraction and transmission electron microscopy study of superconducting FeSe/FeTe multilayers grown by molecular beam epitaxy on SrTiO$ _3$ (001) substrates. While X-ray diffraction confirms perfect in-plane epitaxial alignment between FeSe, FeTe, and the substrate, scanning transmission electron microscopy reveals a surprising lack of atomic registry at the FeSe/SrTiO$ _3$ interface. Instead of adapting to the substrate lattice, FeSe retains its own in-plane lattice spacing. A periodic lateral shift between the atomic positions of FeSe and SrTiO$ _3$ is observed, with a registry recurrence length that matches the lattice mismatch determined by X-ray diffraction. No misfit dislocations or other relaxation features are detected at the interface. This coexistence of directional alignment and registry-free growth suggests an unconventional regime of epitaxy in which crystallographic orientation is maintained without atomic matching. The findings offer insight into strain accommodation in layered systems and may have implications for interface engineering in Fe-based superconductors.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci), Superconductivity (cond-mat.supr-con)
Phys. Rev. Materials 10, 064801 (2026)
Control transition in a temporally random classical spin chain
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Elisha Shmalo, J. H. Pixley, Manas Kulkarni, Sarang Gopalakrishnan, David A. Huse
We theoretically explore a phase transition between controlled and chaotic dynamics in a classical spin chain model subject to chaotic Hamiltonian dynamics and a contractive “control map”, which alternate in time. The control map drives the system toward a target configuration that is an unstable fixed point under the chaotic dynamics. When the control is strong enough, the target configuration is the globally attracting stable fixed point of the dynamics; for weaker control, the many-body dynamics remains chaotic for almost all initial states. The phase transition between controlled and chaotic phases has a mixed character: As the transition is approached from the chaotic phase, the fraction of the spins that are far from the target configuration goes continuously to zero, and there are diverging spatial and temporal correlation lengths; however, the leading Lyapunov exponent is discontinuous across the transition, jumping from a positive value in the chaotic phase to a negative value in the controlled phase. We present evidence that this transition is in the same universality class as directed percolation in the presence of temporal randomness, a universality class for which we obtain results that are consistent with the dynamical Harris criterion but do not saturate the bound.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Chaotic Dynamics (nlin.CD)
13 pages, 11 figures
Crystal Shape and Lattice Deformation in Powder Diffraction
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Matteo Leoni, Alberto Leonardi
Accurate modelling of diffraction peak shapes is essential for extracting microstructural information from nanocrystalline materials. Common-volume functions are widely used to describe finite-size and shape broadening in powder diffraction, but analytical expressions are available only for a limited set of ideal geometries. Here, we introduce a generalized Fourier-based framework in which crystal-domain shape deformation, lattice deformation, and relative shape-lattice misorientation are treated as independently refinable tensor operations within a unified formalism. The approach enables continuous affine transformations of both crystal shape and lattice base while preserving analytical evaluation of directional Fourier coefficients. As a result, complex particle shapes, anisotropic deformations, and arbitrary relative orientations between shape and lattice can be modelled within a single reciprocal- and real-space framework, including coupled shape-lattice transformations not accessible using conventional powder diffraction line-profile methods. The formalism can be applied to individual diffraction peaks, full powder patterns, and total-scattering shape corrections. Validation against virtual scattering experiment data demonstrates that crystal size, shape, lattice deformation, and relative shape-lattice orientation can be simultaneously recovered with high accuracy.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Submitted for publication to the Journal of Applied Crystallography
The group theory of Raman effect in magnetic materials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Rui-Chun Xiao, Xue Liu, Yuxuan Jiang, Hang Zhou, Zi-Hao Feng, Jie Hou, Xiangru Kong, Yujun Zhang
Although Raman scattering in magnetic materials exhibits rich experimental phenomena, the symmetry constraints on Raman tensors have not been fully elucidated. In this work, we use Onsager reciprocity relation, other than the conventional corepresentation method, to deal with the mathematical structures of Raman tensors in magnetic groups. Using this approach, we generate Raman tensor tables for all magnetic point groups, and present a comprehensive understanding of the Raman selection rules in magnetic materials with direct product representations method. Our theoretical and numerical results match previous experiments well, and resolve a puzzle in the Raman spectroscopy of CrSBr. Moreover, we identify a common but overlooked phenomenon: the magneto-Raman vector can be orthogonal to the magnetic moment direction. Our method and associated Raman tensor tables will be helpful for the Raman studies in both experimental and theoretical domains.
Materials Science (cond-mat.mtrl-sci)
Hydride formation and phase separation in palladium nanoparticles from a transferable atomic cluster expansion potential
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Minaam Qamar, Apinya Ngoipala, Matous Mrovec, Matthias Vandichel, Ralf Drautz
The palladium-hydrogen system is a prototype for hydrogen-metal interactions and underpins technologies such as hydrogen storage, catalysis and purification. Yet its nanoscale behaviour – where surface and interface energetics, elastic coherency strain and size-dependent thermodynamics govern phase separation – has eluded accurate atomistic simulation. Empirical potentials misrepresent the energetics of interstitial hydrogen, while existing machine-learning models are restricted to bulk phases at low-hydrogen environments. Here we introduce an atomic cluster expansion (ACE) for Pd-H that reproduces formation energies, phonon spectra, elastic constants, hydrogen migration barriers and surface adsorption with near-DFT accuracy, benchmarked directly against neutron-scattering, high-pressure and lattice-expansion experiments. Its near-linear scaling and CPU efficiency make molecular dynamics of PdH$ _x$ nanoparticles exceeding 28,000 atoms ($ \sim$ 12 nm in diameter) tractable over nanosecond timescales. These simulations resolve, at the atomic scale, the kinetic separation of $ \alpha$ - and $ \beta$ -PdH$ _x$ into a core-shell architecture, reproduce the experimentally observed size dependence of the lattice parameter, and uncover a pronounced hydrogen-induced lowering of the nanoparticle melting temperature. The potential brings experimentally relevant scales of metal-hydride dynamics within quantitative reach.
Materials Science (cond-mat.mtrl-sci)
14 pages, 12 figures
Context-Aware Deep Learning for Defect Classification in Atomic-Resolution STEM
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Jiadong Dan, Cheng Zhang, Leyi Loh, Ivan Verzhbitskiy, Yuan Chen, Goki Eda, Michel Bosman, N. Duane Loh
Artificial intelligence is rapidly advancing materials characterization, yet most applications in electron microscopy rely solely on image contrast, overlooking the chemical and experimental context that shapes image formation. This limitation makes defect classification inherently ambiguous, as similar contrasts can arise from different materials or imaging conditions. Here we develop a context-aware learning framework that integrates image-derived contrast with metadata describing composition, beam energy, and detector geometry. Using a systematically constructed dataset of ~55 million simulated patches spanning 576 cases across 96 doped monolayer transition-metal dichalcogenides, we show that conditioning on contextual variables transforms defect classification from an ill-posed image-only task into a well-posed, physically grounded problem. The framework achieves over 98% accuracy on simulations and near-human agreement on experimental data, with a 94% reduction in posterior entropy. By emphasizing contextual grounding over architectural complexity, this approach links experimental image contrast to the underlying chemical and imaging conditions, supporting physically grounded defect assignments and a general pathway toward multimodal AI models for autonomous materials characterization.
Materials Science (cond-mat.mtrl-sci), Artificial Intelligence (cs.AI)
6 figures
A Robust Agentic Framework for Expert-Level Automation of Atomistic Simulations
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Yutack Park, Yeonwoo Chung, Jinmu You, Jisu Kim, Suyeon Ju, Seungwu Han
Traditionally, atomistic simulation has been constrained by the computational scaling limits of ab initio methods and the parameterization overhead of empirical force fields. The recent emergence of universal machine learning interatomic potentials has significantly mitigated these bottlenecks, offering near-quantum accuracy and generalizability across diverse chemical spaces at a fraction of the computational cost. However, this shift has relocated the bottleneck to the human dimension: time-consuming mechanical processes, such as input preparation and data analysis, now dominate the research lifecycle. We introduce Paimon, a Platform for Agentic Integration in Materials Optimization and Nanoscale-simulations. Through hundreds of trials on an expert-level liquid electrolyte simulation, we show that Paimon substantially improves the reliability of agentic workflows by suppressing silent errors: plausible yet physically incorrect results. We further demonstrate that Paimon can cooperate with an external scientific agent and autonomously reproduce simulation methodologies from the literature. As an agent harness for atomistic simulations, Paimon affords researchers a continuous, science-centric workflow throughout the entire simulation lifecycle.
Materials Science (cond-mat.mtrl-sci)
\textit{\textbf{First-principles}} description of pumped inelastic X-ray scattering: example of K-edge RIXS in graphite
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Elias Richter, Benedikt Maurer, Claudia Draxl
We present an \textit{ab initio} framework for predicting resonant inelastic X-ray scattering (RIXS) in optically pumped materials. Our methodology is based on the Kramers-Heisenberg formula for the double-differential cross section formulated using the results of the Bethe-Salpeter equation (BSE) from many-body perturbation theory. To extend this approach to the time domain, we incorporate non-equilibrium charge-carrier distributions obtained from real-time, time-dependent density-functional theory (RT-TDDFT). Generalizing the RIXS implementation with respect to arbitrary polarizations, allows us to consider different orientations of incoming and outgoing light. We demonstrate our method’s capabilities by studying RIXS at the K-edge of graphite for various non-equilibrium charge-carrier distributions, representing different delay times after optical pumping. Our results reveal angular dependencies in $ \pi$ - and $ \sigma$ -orbital-derived spectral regions, in good agreement with experiment.
Materials Science (cond-mat.mtrl-sci)
10 pages, 8 figures
Free fermions in disguise without exponential degeneracies
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Recently, a number of spin chain models have been discovered that are solvable via hidden free-fermionic structures, going beyond the Jordan-Wigner paradigm. However, all examples in the literature displayed degeneracies that grow exponentially with the volume and that are homogeneous in the spectrum (identical degeneracies for all energy levels). In this note we present a model that can be solved by ``free fermions in disguise’’ (FFD), such that the spectrum is free from exponential degeneracies for generic coupling constants. The model can be seen as a particular perturbation of two Ising chains. Alternatively, it can be realized as an interpolation between a standard Jordan-Wigner solvable chain and the original FFD model of Fendley. We used ChatGPT Pro 5.4 and 5.5 as a research assistant; in the Supplemental Material we provide details about the collaboration between the AI and the human author.
Statistical Mechanics (cond-mat.stat-mech), Exactly Solvable and Integrable Systems (nlin.SI)
37 pages
Planar Hall effect in single and bilayer Rashba systems
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Rahul Biswas, Sunit Das, Amit Agarwal
The planar Hall effect (PHE) is an anisotropic magnetotransport response generated by coplanar electric and magnetic fields. We investigate the PHE in single- and bilayer two-dimensional electron gases (2DEGs) with Rashba spin-orbit coupling and identify two distinct mechanisms: Zeeman coupling and a band geometric channel. In the Zeeman channel, an in-plane magnetic field distorts the Rashba spin-orbit-coupled band dispersion and generates anisotropic carrier velocities, producing a finite PHE. In an asymmetric Rashba bilayer, interlayer electronic delocalization generates finite planar Berry curvature and orbital magnetic moment components, giving rise to a band geometric PHE channel. Using semiclassical Boltzmann transport theory, we calculate the chemical potential and angular dependence of the planar Hall conductivity for both mechanisms. Symmetry analysis shows that the leading response is quadratic in the magnetic field and exhibits the characteristic $ \pi$ -periodic angular dependence. For the parameter regime considered here, the Zeeman-induced contribution dominates, while the band geometric channel provides a distinct symmetry-allowed contribution unique to asymmetric Rashba bilayers. Our results reveal microscopic origins of anisotropic magnetotransport in spin-orbit-coupled two-dimensional materials.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
Comments are welcome
Controlled component segregation in vapor-deposited organic semiconductor glass mixtures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Shinian Cheng, Yejung Lee, Lian Yu, Mark D. Ediger, Dean M. DeLongchamp, Camille E. Bishop
Multicomponent vapor-deposited organic glasses are essential in organic electronic applications, but achieving controlled component segregation at the nano- and mesoscale remains a challenge, hindering the rational development of high-performance devices. In this study, we investigate binary organic semiconductor mixtures of TPD (N,N’-Bis(3-methylphenyl)-N,N’-diphenylbenzidine) and TCTA (Tris(4-carbazoyl-9-ylphenyl)amine). Despite being miscible in the bulk liquid state, the co-deposited glassy films of these two organic semiconductors exhibit a range of segregation behaviors, from homogenous to clearly phase-separated structures. We employed differential scanning calorimetry and resonant soft X-ray scattering (RSoXS) to study the component segregation behavior and used the National Institute of Standards and Technology RSoXS Simulation Suite, paired with Atomic Force Microscopy, to interpret the energy-dependent RSoXS spectra. Our results indicate that component segregation in co-deposited TPD-TCTA films is due to a kinetically-arrested nucleation-and-growth mechanism, in contrast to the segregation mechanism of a previously reported TPD-DO37 (disperse orange 37) mixture which is strongly immiscible in bulk. This work provides a demonstration of tunable molecular aggregation in organic semiconductor glasses, enabling access to a continuum of morphologies from homogeneously mixed to segregated phases.
Materials Science (cond-mat.mtrl-sci), Soft Condensed Matter (cond-mat.soft)
32 pages, 7 figures
Scaling Behaviors of Work Cumulants in Slow Isothermal Processes
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Ruohan Xu, Yanbo Qiao, H. T. Quan
We study the cumulants of work in a slow isothermal process for gapped systems. Using the Martin-Siggia-Rose-De Dominicis-Janssen (MSRDJ) formalism and the properties of connected correlation functions, we show that in this process, the $ n$ -th cumulant of work scales as $ 1/T^{n-1}$ , where $ T$ is the time duration. This result holds generally for arbitrary smooth protocols. Furthermore, we derive the coefficients of the cumulants from equilibrium properties. These coefficients are found to be relevant to thermodynamic geometric tensors.
Statistical Mechanics (cond-mat.stat-mech)
Predicting Physical and Physical-Chemical Properties of Molecular-Based Materials Using Computational Neural Networks
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Andrei A. Gakh, Bobby G. Sumpter, Donald W. Noid
A computational scheme, which utilizes neural networks, was developed to predict properties of molecular-based materials from chemical structures. The method uses a set of simple algorithms to encode the structure and composition of organic molecules directly into numerical vectors, which is used as input for neural networks. Backpropagation type neural networks are then used to correlate these numeric inputs with a set of desired properties. Calculated results for a series of hydrocarbons, hydrofluorocarbons, and crown ethers demonstrate average accuracies of 0.2-8.1% with maximum deviations of 16-20% for a broad range of thermodynamic, physical, and physical-chemical characteristics (heat capacity, enthalpy, heat of evaporation, boiling point, density, refractive index, stability constants, etc.). In addition, a number of physical and mechanical properties were estimated for polymeric materials and compared with regression analysis. Based on the neural network capabilities of formulating accurate quantitative structure property relationships, a technique called computational synthesis is suggested for performing materials design.
Materials Science (cond-mat.mtrl-sci), Soft Condensed Matter (cond-mat.soft)
31 pages, 9 figures
International Journal of Smart Engineering System Design, 1, 255-272 (1998)
Deviations from Debye’s specific heat due to excess energy fluctuations
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
Ralph V. Chamberlin, Sumiyoshi Abe
Measured specific heats often exceed Debye’s T^3-law, even in high-purity single crystals. Analogous excess energy fluctuations in molecular dynamics (MD) simulations of crystals with no defects come from fast energy modulations involving next-nearest-neighbor atoms. Here, a theory is developed for these modulations, based on time- and phase-averaging followed by thermal averaging. This order of averaging is guided by evidence from the simulations and various experimental techniques showing that localized excitations are decoupled from the heat bath. Emergent nonextensivity is interpreted by analogy with anomalous diffusion. The theory modifies the standard relation between energy fluctuations and specific heat, giving good agreement with the simulations and new insight into many measurements. The theory may also provide a basis for understanding excess specific heat in amorphous materials and anomalous noise in quantum devices.
Statistical Mechanics (cond-mat.stat-mech), Disordered Systems and Neural Networks (cond-mat.dis-nn), Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Materials Science (cond-mat.mtrl-sci)
14 pages, 3 figures
Stoichiometric Epitaxial Strontium Titanate Thin Films on Silicon by High-Temperature Sr Segregation
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Andries Boelen, Marina Baryshnikova, Maxim Korytov, Sean R. C. McMitchell, Felix Cahyadi, Christian Haffner, Clement Merckling
Thin-film strontium titanate (SrTiO$ _3$ , STO) layers grown on silicon require accurate stoichiometry and single-crystalline order to exploit their functional properties optimally. Oxide molecular beam epitaxy can provide an epitaxial interface, but suffers from source oxidation and resulting flux instabilities, yielding only a narrow growth process window for cationic stoichiometry control. Here, we investigate post-growth annealing in oxygen as a pathway to drive the STO layer toward stoichiometry in intentionally Sr-rich epitaxial STO films on silicon (001). Annealing over a broad temperature range revealed two distinct Sr-segregation mechanisms. Below 800 °C, excess Sr segregates toward the surface, forming SrO outgrowths that progressively sublimate at elevated temperatures. Above 800 °C, a second mechanism dominates: Sr accumulates within the interfacial SiO$ _2$ layer formed by oxygen diffusion at the STO/Si interface. Together, these mechanisms effectively remove excess Sr from the STO lattice, yielding a more stoichiometric perovskite layer. Our results demonstrate that growing slightly Sr-rich STO templates followed by controlled annealing provides a practical route to improve crystalline quality, offering a scalable strategy for high-quality STO integration on silicon.
Materials Science (cond-mat.mtrl-sci)
k-Means Clustering in Fingerprint-Based Configuration Selection for Fitting Interatomic Potentials
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Miroslav Lebeda, Jan Drahokoupil, Ludvík Löbel, Petr Vlčák
In this study, we present a method for selecting an arbitrary number of distinct configurations from a larger data set by applying k-means clustering to atomistic configuration fingerprints based on the CrystalNN model and radial distribution function (RDF). This approach improves the accuracy of fitting classical molecular dynamics interatomic potentials to density functional theory (DFT) data for both energies and forces while requiring fewer configurations than random selection. We demonstrate this improvement by fitting an embedded-atom method (EAM) potential for titanium, using various configurational sizes from an initial set of 1800 configurations. The k-means clustering consistently achieves better precision and lower standard deviations for a smaller number of configurations than random selection. The results also suggest that only about 30 configurations are sufficient to obtain an EAM model that describes well the full set of 1800 configurations in terms of energies and forces. Additionally, t-distributed stochastic neighbor embedding (t-SNE) method was used to reduce the configuration fingerprints into 2D space, and it revealed an overlap between two configuration subsets with and without Ti vacancy, indicating similar atomic environments. This similarity is captured by k-means clustering but not by random selection. Furthermore, when the overlapping configurations with vacancies were excluded from the k-means algorithm and used only as a test set, their energy and force predictions showed similar precision to those when they were included. This indicates that the overlapping configurations in the 2D t-SNE space indeed imply potential information redundancy among the atomistic configurations.
Materials Science (cond-mat.mtrl-sci)
Journal of Chemical Theory and Computation 20.23 (2024): 10676-10683
ARTGEL: A temperature-regulated electrophoresis platform for quantitative studies of reversible association in gels
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Here we present ARTGEL, an actively regulated-temperature gel electrophoresis platform designed for long-duration experiments under independently controlled thermal and electrical conditions. ARTGEL combines thermoelectric regulation of the gel temperature, a large heated and circulated buffer reservoir, and an automated electrode-wiping mechanism that stabilizes the voltage across the gel during runs exceeding 24 h. The platform was developed to address a limitation of conventional electrophoretic mobility shift assays, which are commonly used to analyze reversible biomolecular association but usually aim to suppress reaction during electrophoresis by dilution, competitors, or reduced temperature so that the gel reports a pre-equilibrated bulk solution. For temperature-sensitive systems, these strategies can alter the chemical state during loading and migration and obscure whether the measured band pattern reflects the original bulk sample or a re-equilibrated state inside the porous gel. Rather than attempting to quench reactions, ARTGEL enables electrophoresis to be performed at the same temperature as complementary bulk measurements, so that reversible association can be quantified directly in the gel and compared with matched measurements in solution. Using DNA origami assemblies, we show that ARTGEL preserves distinct temperature-dependent association states, resolves reaction-dependent distortions of migrating bands, and supports extraction of in-gel kinetic and thermodynamic parameters from reaction-diffusion-advection modeling.
Soft Condensed Matter (cond-mat.soft), Instrumentation and Detectors (physics.ins-det)
Lattice genome: representation and analysis of heterogeneous crystalline microstructures
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Jiayang Wang, Mathieu Calvat, J.C. Stinville, Marat I. Latypov
Inspired by the concept of a generalized materials genome, we introduce the notions of lattice gene and lattice genome for crystalline materials. A lattice gene is a compact representation of the local crystalline structure obtained by encoding the Kikuchi diffraction patterns with a variational autoencoder. We show that this representation satisfies key criteria for a materials gene: compactness, experimental accessibility, existence of a distance metric reflecting structural similarity, and sufficient information content for reconstructing the original diffraction patterns. The lattice genome is the spatially resolved collection of lattice genes across a representative area mapped by electron backscatter diffraction (EBSD), which captures mesoscale heterogeneity that ultimately controls properties. We demonstrate three applications of the lattice genome: (i) latent component maps that visualize grain-scale and intra-grain heterogeneities, (ii) domain segmentation based on distance and angle metrics in the latent space, and (iii) kernel and domain latent vector spreads that quantify intragranular heterogeneity as high-dimensional analogs of kernel average misorientation and grain orientation spread. All three tools are validated on microstructures of additively manufactured and wrought Ni-base superalloys in as-built and recrystallized conditions.
Materials Science (cond-mat.mtrl-sci)
Evolution of terahertz third harmonic response across rare-earth nickelate phase-diagram
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Gulloo Lal Prajapati, Igor Ilyakov, Alexey Ponomaryov, Atiqa Arshad, Sanjeev Kumar, Jayaprakash Sahoo, Dhanvir Singh Rana, Abdelrahman Azab, Friedemann Queisser, Ralf Schützhold, Jan-Christoph Deinert
High harmonic generation (HHG) is a sensitive probe for investigating electronic structures and dynamics of materials and a source for attosecond pulses. In particular, HHG with terahertz (THz) light can enable probing of nonlinear responses in correlated materials arising from low-energy many-body interactions. However, THz HHG studies have so far largely focused on topological materials and superconductors, leaving out other potential material systems which could also become efficient THz HHG sources. Here, we report THz third harmonic generation (THG) in rare-earth nickelates – a prototype material for exploring the Mott insulator-metal transition and related technological applications. We find that the THG amplitude is highly sensitive to the strengths of electronic and magnetic phases of nickelates. In films with sharp phase-transitions, the local maximum and minimum in the temperature-dependent THG amplitude coincide with insulator-metal and magnetic transition temperatures, respectively. While in films with weaker transitions, these features shift toward lower temperatures or even monotonous THG enhancement is observed down to low temperatures. We developed a generalized theory for THz harmonic generation in negative charge-transfer insulators and outlined strategies to enhance the THz nonlinearities further. Our study broadens the scope of THz HHG studies and related applications to strongly correlated materials.
Strongly Correlated Electrons (cond-mat.str-el), Materials Science (cond-mat.mtrl-sci)
Uniaxial-Stress-Induced Magnetic Transitions in the Triangular-Lattice Antiferromagnet PdCrO2
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Nina Stilkerich, Tobias Ritschel, Hilary M. L. Noad, Richard Waite, Dmitry Khalyavin, Kousuke Ishida, Pascal Manuel, Fabio Orlandi, Seunghyun Khim, Elena Gati, Andrew P. Mackenzie, Jochen Geck, Clifford W. Hicks
Uniaxial stress is a promising method to tune magnetic frustration, allowing its effects to be studied in a precise way. In this work, uniaxial stress is applied to the triangular-lattice antiferromagnet PdCrO2. The Cr-Cr magnetic interaction is very sensitive to interatomic separation, so laboratory-achievable stress can induce substantial changes in magnetic structure. Results from three types of measurement are presented: X-ray diffraction, the stress-strain relationship, and neutron diffraction. The combined data show that the elastic moduli of PdCrO2 are strongly affected by stress-induced changes in magnetic structure. A new, first-order stress-induced magnetic transition is observed, at which the lattice constant shrinks by 0.21%. The lattice stiffens dramatically across this transition: the Young’s modulus increases by about 80 GPa, and the Poisson ratio falls from about 1 to about 0.4. This stiffening indicates that the magnetic order “locks,” that is, becomes insensitive to lattice strain. This locking might occur because the new stress-induced magnetic order nests the Fermi surface of the Pd sheets. Other frustrated magnets, including candidate spin liquids, may show similarly strong coupling between magnetic and elastic degrees of freedom.
Strongly Correlated Electrons (cond-mat.str-el)
16 pages. To be published in Reports on Progress in Physics
The Map of Parameter Space in Double Microwave Shielding
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-09 20:00 EDT
Hubert J. Jóźwiak, Ian Stevenson, Sebastian Will, Tijs Karman
Double microwave shielding employs $ \sigma^{+}$ - and $ \pi$ -polarized microwave fields, tuned close to the lowest rotational transition, to engineer a long-range repulsive barrier between polar molecules. By preventing molecules from reaching the short range, this technique suppresses detrimental two-body losses and recently enabled the realization of molecular Bose-Einstein condensates and self-bound droplets. Yet, the optimal operating regimes of the shielding mechanism remain largely unexplored. Here, by leveraging the underlying universality of the scattering problem, we systematically map the four-dimensional microwave parameter space-spanned by the detunings and intensities of the two fields-to identify configurations that maximize both shielding efficiency and interaction tunability. We define optimal operating regimes as configurations that are strictly free of field-linked bound states while sufficiently suppressing two-body losses to exceed typical lifetimes of ultracold samples. In these regimes, we evaluate the elastic-to-inelastic collision ratios required for efficient evaporative cooling and explore the accessible tuning range of the effective dipolar interactions. Finally, to identify the best platforms for future quantum simulation experiments, we conduct a global survey of candidate molecular species under realistic field constraints. We identify heavy, strongly dipolar molecules as the most promising candidates, demonstrating that they can achieve extreme loss suppression alongside robust interaction tunability using only moderate field strengths.
Quantum Gases (cond-mat.quant-gas), Atomic Physics (physics.atom-ph), Chemical Physics (physics.chem-ph), Quantum Physics (quant-ph)
Ab initio parametrization of distributed polarizable force fields
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Felix Post, Jean-Philip Filling, Toulik Maitra, Falk May, Michael Wand, Denis Andrienko
Polarizable force fields offer superior transferability and accuracy compared to classical force fields, enabling access to electronic response properties such as refractive index and electronic density of states. Here, we demonstrate two key improvements that significantly enhance their accuracy: (1) assigning atomic polarizability to individual atoms rather than atom types, and (2) employing atomic polarizability tensors instead of scalar values. These modifications extend the applicability of polarizable force fields to cations, anions, and excited states, while also providing more accurate descriptions of neutral molecules. We propose a first-principles-based parameterization procedure for atomic polarizability tensors and scalars, validated on a set of small organic molecules with conjugated building blocks. To overcome the computational cost of ab initio calculations, we train a message-passing graph neural network to predict polarizability parameters, enabling efficient and scalable parameterization. Crucially, this approach imposes no additional computational cost during simulations and provides a clear diagnostic criterion for identifying cases where polarizable force field models fail to accurately describe molecular polarizability.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Geometric Dissipation Constraints in Stochastic Reaction Dynamics: A Variational Observable for Hidden Kinetic Structure in Energy Landscapes
New Submission | Statistical Mechanics (cond-mat.stat-mech) | 2026-06-09 20:00 EDT
We propose a geometric framework for characterizing hidden kinetic constraints in stochastic reaction dynamics. While free-energy barriers and entropy production provide global descriptors of thermodynamic behavior, they are largely insensitive to local geometric structure in configuration space that governs pathway selection. Starting from overdamped Langevin dynamics formulated as a gradient flow in Wasserstein space, we derive a variational functional whose leading-order asymptotic structure defines a local dissipation-geometry coupling observable. This quantity combines force-drift alignment with phase-space contraction induced by the divergence of the drift field, yielding a scalar field that reflects second-order geometric features of the underlying energy landscape. We demonstrate that this observable distinguishes kinetically distinct reaction channels that are degenerate under conventional free-energy analysis, as shown through numerical experiments on benchmark systems including the Muller-Brown potential, corrugated periodic landscapes, and the conformational transitions of Alanine Dipeptide. These experiments demonstrate robust separation of pathways and are consistent with a quadratic scaling behavior in the high-frequency homogenization regime. Our results suggest that stochastic reaction dynamics contain an additional geometric layer of kinetic control in molecular motion not captured by standard thermodynamic or reaction-coordinate descriptions.
Statistical Mechanics (cond-mat.stat-mech)
5 pages, 3 figures
Crystallography of periodic nanotextures in a strained Mott insulator
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Benjamin Z. Gregory, Yorick A. Birkhölzer, Noah Schnitzer, Ziming Shao, Jeff Hodgson, Suchismita Sarker, Jacob P. Ruff, Berit H. Goodge, David A. Muller, Kyle M. Shen, Darrell G. Schlom, Andrej Singer
Here we investigate stripes of alternating structural phases spontaneously forming in epitaxially strained $ Ca_2RuO_4$ thin films below the metal-insulator transition. Using large-volume X-ray reciprocal-space mapping, we show that satellite-pattern intensities across 24 symmetry-inequivalent Bragg reflections collapse onto a single parameter-free curve. The collapse identifies a coherent martensitic laminate of few-nm-wide domains separated by $ {012}$ interfaces, with displacements along $ \left\langle01\bar{2}\right\rangle$ . Satellite-extinction analysis demonstrates that both coexisting phases retain the bulk orthorhombic space group despite the pseudocubic $ LaAlO_3$ substrate, biaxial epitaxial strain, and intrinsic strain at the interfaces. Classical invariant-plane-strain crystallography thus governs the nanoscale domain geometry of a Mott insulator with intertwined magnetic, electronic, and lattice order.
Materials Science (cond-mat.mtrl-sci), Strongly Correlated Electrons (cond-mat.str-el)
Elastoinertial effects govern dynamic response of soft hair beds
New Submission | Soft Condensed Matter (cond-mat.soft) | 2026-06-09 20:00 EDT
Jonas Smucker, Naiesa Freeman, Eric Caballero, Philip J. Morrison, José Alvarado
Fluid-immersed hair beds are ubiquitous in biology-from the endothelial glycocalyx and primary cilia to intestinal microvilli-where they serve as mechanosensors that transduce dynamic flow signals into biochemical regulatory responses. Despite the inherently dynamic nature of physiological flows, the dynamic mechanical properties of fluid-immersed hair beds under time-varying conditions remain poorly characterized. Here we investigate the transient rheological response of elastic hair beds to large-amplitude oscillatory shear flows at low to intermediate Reynolds number. While the hairs and fluid themselves obey linear constitutive laws, their coupled interaction produces a dynamic nonlinear response that depends sensitively on driving frequency and amplitude. We identify a crossover from a stress-lagging regime to a stress-leading regime, which is governed by an interplay between fluid viscosity, fluid inertia, and hair elasticity. A simplified rigid-beam model qualitatively captures the crossover behavior. Characterizing the dynamic flow response of soft hair beds has direct biological implications, since the lag time sensitively determines the stability of mechanosensory signaling in the feedback loops underlying essential biological processes such as vasodilation, ciliary remodeling, and tubular reabsorption. Our results establish a framework for understanding how the physical properties of biological hair beds optimize dynamic information transmission during mechanotransduction.
Soft Condensed Matter (cond-mat.soft)
Research article
Bi-S network origin of cation-disorder stability and dispersive band edges in AgBiS2
New Submission | Materials Science (cond-mat.mtrl-sci) | 2026-06-09 20:00 EDT
Han-Pu Liang, Songyuan Geng, Heng Kang, Chen Qiu, Xiao-Ping Yao, Qing’an Li, Bozhao Zhang, Lechuan Sun, Yuxuan Chen, Shan Zhang, Su-Huai Wei, Peng-Fei Guan
Cation-disordered AgBiS2 is a promising lead-free optoelectronic material, but both its ordered structure and the microscopic origin of its favorable electronic properties remain debated. Theory has proposed a mixed-coordination tendency with tetrahedral AgS4 and octahedral BiS6 units, whereas experiments mainly report octahedrally coordinated ordered and cation-disordered phases, together with local cation off-centering. Here, we combine a machine-learning interatomic potential with a deep-learning Hamiltonian to resolve the coupled structural and electronic evolution of AgBiS2 at large length scales. We identify the three-dimensional Bi-S network as the central structural motif governing both disorder stability and band-edge electronic states. At weak disorder, Ag/Bi exchange competes with the off-centering tendency of the Ag sublattice, producing strongly distorted local environments and convoluted diffraction signatures that hinder the identification of the ordered phase. With increasing disorder, BiS6-like units connect into a continuous Bi-S network, which stabilizes the rocksalt-like disordered phase. Despite strong cation disorder, AgBiS2 retains clear semiconductor-like band dispersion and develops a direct band gap. The connected Bi:p-S:p states supported by the Bi-S network preserve a dispersive conduction-band edge and a small electron effective mass. In contrast, mobile Ag disrupts the long-range periodicity of Ag-S bonding, leading to strongly localized valence states. These results clarify the structural controversy in ordered AgBiS2 and establish a unified physical picture of disorder stability and optoelectronic response in nonisovalent semiconductor alloys.
Materials Science (cond-mat.mtrl-sci), Computational Physics (physics.comp-ph)
Analog quantum simulation of chiral magnetic dynamics using optical superlattices
New Submission | Quantum Gases (cond-mat.quant-gas) | 2026-06-09 20:00 EDT
We propose an analog quantum simulation of chiral magnetic dynamics using ultracold atoms in an optical superlattice. The massive Schwinger model in the zero gauge coupling limit maps onto the Rice-Mele model, with the fermion mass and topological angle encoded in the superlattice parameters. We study the real-time dynamics of the vector current following two quench protocols that drive continuous chirality injection and chirality relaxation. Simulations with realistic superlattice parameters and experimental noise demonstrates clear mass dependence of the current dynamics in both protocols, robust against experimental imperfections. The vector current may be directly measurable via single-bond-resolved detection, establishing cold atom superlattices as a viable platform for probing non-equilibrium chiral phenomena.
Quantum Gases (cond-mat.quant-gas), High Energy Physics - Lattice (hep-lat), Quantum Physics (quant-ph)
Comments welcome !
Frequency-resolved decoherence spectroscopy of a semiconductor charge qubit coupled to a high-impedance resonator
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Ekaterina Al-Tavil, Wonjin Jang, David J. van Woerkom, Ville Maisi, Stefano Bosco, Jan A. Krzywda, Jeroen Danon, Christian Reichl, Werner Wegscheider, Thomas Ihn, Klaus Ensslin, Andreas Wallraff, Pasquale Scarlino
Superconducting resonators coupled to semiconductor quantum dots provide a powerful platform to investigate light-matter interaction and decoherence mechanisms in solid-state quantum systems. Here we study a hybrid circuit quantum electrodynamics architecture consisting of a GaAs double-quantum-dot charge qubit capacitively coupled to a high-impedance, frequency-tunable SQUID-array resonator. By tuning the qubit transition frequency over the range $ \omega_\mathrm{q}/2\pi \sim 3$ -$ 6$ GHz, we perform frequency-resolved decoherence spectroscopy of the charge qubit across a broad energy window. Time-resolved measurements enable us to disentangle relaxation and pure dephasing processes and to identify distinct decoherence regimes as a function of qubit frequency. We find that at lower frequencies ($ \leq 4.5$ GHz) dephasing dominates the qubit linewidth, whereas at higher frequencies energy relaxation becomes the leading contribution. The measured frequency dependence of the relaxation rate exhibits a cubic scaling, consistent with charge-qubit decay dominated by coupling to a piezoelectric phonon bath and providing frequency-resolved access to the corresponding phonon-induced spectral density. Our results show that hybrid semiconductor–superconducting circuits can serve as sensitive spectroscopic tools to probe microscopic decoherence mechanisms relevant for a wide range of hybrid quantum devices.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Quantum Physics (quant-ph)
Radiowave-induced Resistance Oscillations
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
E. Bell, C. Hnatovsky, K. W. Baldwin, L. N. Pfeiffer, K. W. West, S. Studenikin, M. A. Zudov
Microwave-induced resistance oscillations (MIROs) \cite{zudov:2001a} occur when a 2D electron gas is subjected to radiation of frequency $ \omega = 2 \pi f$ and varying magnetic field $ B$ . MIROs are periodic in $ 1/B$ , with the period determined by the radiation frequency $ \omega$ , and their amplitude scales with the radiation power. Stepping from single-photon transitions between Landau levels, MIROs are found on the lower-field side of the cyclotron resonance, $ \omega_c \lesssim \omega$ , where $ \omega_c$ is the cyclotron frequency. Here, we report on experimental observation of another class of magneto resistance oscillations, which are also induced by radiation, but in the radio frequency (UHF band) range. These oscillations are distinct from MIROs in the following aspects: (i) they occur at $ \omega_c \gg \omega$ , (ii) their amplitude is independent of radiation power, (iii) their period is controlled by the radiation electric field, rather than by $ \omega$ , and (iv) they can be either $ 1/B$ or $ 1/B^2$ -periodic, depending on $ B$ . We further show that these oscillations can be explained by a displacement model in the limit of short-range disorder.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
5 pages, 5 figures
Proximity-induced orbital antiferromagnetism in Ising superconductors
New Submission | Superconductivity (cond-mat.supr-con) | 2026-06-09 20:00 EDT
G. A. Bobkov, V. A. Bobkov, T. Karabassov, I. V. Bobkova, A. A. Golubov
We predict a fundamentally new superconducting state in superconductor/antiferromagnet heterostructures with Ising spin–orbit coupling: proximity-induced orbital antiferromagnetism. In this state, the order parameter acquires a periodic phase modulation locked to the magnetic lattice, generating atomic-scale loop currents with opposite orbital moments on neighboring unit cells. Its emergence requires at least three nonequivalent magnetic sublattices per unit cell and finite spin–orbit coupling. Using NbSe$ _2$ /MnPS$ _3$ as a concrete example, we combine first-principles and Bogoliubov–de Gennes calculations to demonstrate that the proximity-induced exchange field leads to robust phase modulation. Unlike FFLO and helical states, the phase gradient is atomic-scale, the state is current-carrying, and it remains uniquely stable over the full parameter range. The state manifests as characteristic finite-energy dips in the local density of states, accessible by STM.
Superconductivity (cond-mat.supr-con)
Persistent currents, whirlpools, and local Chern markers in twisted TMD Chern insulators
New Submission | Mesoscale and Nanoscale Physics (cond-mat.mes-hall) | 2026-06-09 20:00 EDT
Francesco Cioni, Lorenzo Cavicchi, Nazzareno Africani, Giacomo Mazza, Fabio Taddei, Amir Yacoby, Marco Polini
Recent materials advances have made it possible to fabricate twisted transition metal dichalcogenide homobilayers. These systems have been shown to host integer and fractional Chern insulating states. Because of spontaneous time reversal symmetry breaking, their ground state harbors intriguing spin-polarized currents with whirlpools on the moiré length scale that can be measured by scanning probe methods. We first provide a quantitative analysis of these persistent currents and then show that the maximum of the amplitude of the current density in the bulk of the sample is an accurate tracker of topological order. We conclude by calculating how the quantization of the Hall conductance is affected by finite-size effects.
Mesoscale and Nanoscale Physics (cond-mat.mes-hall), Strongly Correlated Electrons (cond-mat.str-el)
7 pages, 4 figures + Supplemental Material
Topological Triplons in the Pinwheel Valence Bond Solid on the Kagome Lattice
New Submission | Strongly Correlated Electrons (cond-mat.str-el) | 2026-06-09 20:00 EDT
Laura Calonge-Martínez, Peng Rao, Frédéric Mila, Johannes Knolle
We investigate the triplon excitations of the pinwheel valence-bond-solid phase on the deformed kagome lattice compound Rb2Cu3SnF12. Using bond-operator mean-field theory, we compute the triplon band structure, dynamical structure factor, Berry curvatures and the associated thermal Hall response. We show that the presence of Dzyaloshinskii-Moriya interactions and an external magnetic field are key for endowing triplon bands with nontrivial Chern numbers. We find good qualitative agreement of the low-energy dynamical structure factor with neutron-scattering experiments. An applied magnetic field can isolate the lowest triplon Chern band leading to a tunable thermal Hall conductivity for accessible temperature and field regimes. Our results establish the deformed kagome pinwheel valence-bond solid as a promising platform for topological triplon physics and for observing the associated thermal Hall effect.
Strongly Correlated Electrons (cond-mat.str-el)