Showing 1–50 of 564 results for author: Li, G

Transport-defined photodetection through electrically selectable nonequilibrium carrier transport

Authors: Jiaxuan Cai, Yan Xie, Ning Yang, Weidong Chu, Peng Bai, Lianhe Li, Edmund H. Linfield, Hanbing Wang, Meng Chen, Guanchen Li, Yingxin Wang, Ziran Zhao

Abstract: Broadband optical fields can change in both intensity and spectral distribution, but a fixed-response detector maps this evolving information onto a single electrical signal. Here we demonstrate transport-defined photodetection, in which electrical bias selects how photoexcited carriers are redistributed, escape and are collected, creating complementary response functions within one shared active… ▽ More Broadband optical fields can change in both intensity and spectral distribution, but a fixed-response detector maps this evolving information onto a single electrical signal. Here we demonstrate transport-defined photodetection, in which electrical bias selects how photoexcited carriers are redistributed, escape and are collected, creating complementary response functions within one shared active region. In a GaAs/AlGaAs semiconductor ratchet, light-driven ratchet transport defines the response at 0 V, whereas the spectral evolution at -2 V is consistent with field-assisted hot-carrier transport. The overlapping states span a measured spectral range of 0.4-94.5 μm at 5 K, provide state-dependent calculated detection floors and support joint infrared operation at 30 K. Direct optical beat notes at 7.432 GHz in the mid-infrared and 17.103 GHz in the terahertz demonstrate optical-to-electrical conversion. Their common-path outputs recover an imposed spatial temperature gradient and the transient field-of-view-integrated effective radiation temperature of laser-excited graphite. These results establish post-photoexcitation transport as a function-defining design variable for semiconductor photodetectors, complementing structure-defined, field-tuned and optically encoded approaches to reconfigurable photodetection. △ Less

Submitted 16 August, 2026; originally announced August 2026.

Comments: 18 pages, 6 figures

Shortcuts to Parameter Sweeps

Authors: Chi Xiang, Guodong Cheng, Geng Li

Abstract: Efficient evaluation of stationary parametric sensitivities over broad parameter ranges is important for identifying influential training data, fitting force fields, and predicting material responses, but standard pointwise approaches require repeated relaxation and sampling. Here we introduce Shortcuts to Parameter Sweeps (STPS), an engineered control strategy that uses an auxiliary control to tr… ▽ More Efficient evaluation of stationary parametric sensitivities over broad parameter ranges is important for identifying influential training data, fitting force fields, and predicting material responses, but standard pointwise approaches require repeated relaxation and sampling. Here we introduce Shortcuts to Parameter Sweeps (STPS), an engineered control strategy that uses an auxiliary control to transport the probability density along a prescribed family of instantaneous stationary states during a finite-time parameter sweep. This enables the continuous response curve over the full parameter interval to be estimated from a single controlled sweep using covariance-based response relations. STPS applies to both equilibrium and nonequilibrium steady-state systems, including those with unknown stationary distributions, and can be implemented directly using stationary samples in high-dimensional settings. Numerical tests on single-particle and interacting many-body systems show that STPS yields response curves in close agreement with reference results. These findings establish STPS as an efficient, sample-based framework for continuous sensitivity analysis in stochastic simulations. △ Less

Submitted 12 August, 2026; originally announced August 2026.

Comments: 6 pages main text, 2 figures; 11 pages supplemental material

Process-fracture mapping of a DLP-printed photopolymer using Bayesian active learning and surrogate-based sensitivity analysis

Authors: Ethan Blackwell, Yogesh C. Chandrashekar, Guoqiang Li, Kshitiz Upadhyay

Abstract: Digital light processing (DLP) enables rapid fabrication of polymer structures, but fracture performance depends on multiple interacting processing variables, making exhaustive experimental characterization impractical. This work presents a data-efficient framework for process-fracture mapping of a DLP-printed photopolymer using Bayesian active learning and digital image correlation (DIC)-assisted… ▽ More Digital light processing (DLP) enables rapid fabrication of polymer structures, but fracture performance depends on multiple interacting processing variables, making exhaustive experimental characterization impractical. This work presents a data-efficient framework for process-fracture mapping of a DLP-printed photopolymer using Bayesian active learning and digital image correlation (DIC)-assisted Mode I fracture experiments. Four processing parameters were considered: layer angle, UV exposure time, layer height, and print temperature. Fracture resistance was quantified by the critical J-integral, $J_c$, obtained from three-point-bending tests with DIC-based evaluation of crack-mouth opening displacement and hinge-point kinematics. Beginning with two randomly selected conditions, Gaussian process regression (GPR) and a modified upper confidence bound (UCB)-style acquisition function selected 26 additional experiments, yielding 28 processing conditions with three replicates each. The final GPR surrogate reproduced the training data with $R^2=0.99$ and achieved leave-one-out cross-validation performance of $R^2=0.63$ and Pearson $r=0.81$. Surrogate-based sensitivity analysis quantified parameter effects and global contributions. One-at-a-time response curves revealed nonlinear conditional trends, while global Sobol analysis identified UV exposure time as the dominant processing variable, with first-order and total-order indices of 0.6780 and 0.7581, respectively. Based on total-order influence, the parameters ranked as UV exposure time, layer angle, print temperature, and layer height. The first-order Sobol indices summed to 0.8058, indicating non-negligible interaction and higher-order effects. These results demonstrate that Bayesian-active-learning-guided experimentation can efficiently recover process-fracture relationships and parameter interactions from a sparse experimental campaign. △ Less

Submitted 11 August, 2026; originally announced August 2026.

Bulk Ising superconductivity in an intercalated TaSe2 bilayer structure

Authors: Yupeng Li, Zhaopeng Guo, Lihong Hu, Guoan Li, Siqi Wu, Xinyi Zheng, Xiao Deng, Zhiyuan Zhang, Anqi Wang, Xingchen Guo, Ziwei Dou, Peiling Li, Yuke Li, Fanming Qu, Guangtong Liu, Jin-Ke Bao, Guang-Han Cao, Li Lu, Jie Shen, Zhu-An Xu

Abstract: Ising spin-orbit coupling in bulk systems has drawn considerable interest for its ability to conveniently construct spin-orbit environments and enable exotic quantum phenomena. In this work, we synthesize intercalated 2Hb-TaSe$_2$ bilayers with noncentrosymmetric structure and, through multifaceted analysis, present multiple lines of evidence for the emergence of bulk Ising superconductivity. Resi… ▽ More Ising spin-orbit coupling in bulk systems has drawn considerable interest for its ability to conveniently construct spin-orbit environments and enable exotic quantum phenomena. In this work, we synthesize intercalated 2Hb-TaSe$_2$ bilayers with noncentrosymmetric structure and, through multifaceted analysis, present multiple lines of evidence for the emergence of bulk Ising superconductivity. Resistivity measurements reveal anisotropic superconducting behavior, with a remarkably large in-plane upper critical field $B_{c2}^{\|}$ that exceeds the Pauli limit $B_{p}$. Band structure calculations further show band splitting accompanied by out-of-plane spin polarization. Collectively, these observations point to the presence of Ising superconductivity. Additional measurements of the thickness-dependent ratio $B_{c2}^{\|}$/$B_{p}$ and the superconducting diode effect not only further support the Ising superconducting nature of this material, but also reveal additional features of bulk Ising superconductivity evolving with thickness. Our findings provide valuable insights that may contribute to the search for bulk Ising superconductors. △ Less

Submitted 2 August, 2026; originally announced August 2026.

Comments: 8 pages, 4 figures

Metamagnetism in UTe2: the roles of itinerancy and localization

Authors: Theodore I. Weinberger, Daniel Shaffer, Zheyu Wu, Dmitry V. Chichinadze, Jinxu Pu, Gang Li, Rui Zhou, Yurii Skourski, Dave Graf, Andrej Cabala, Vladimir Sechovsky, Michal Valiska, Michal P. Kwasigroch, F. Malte Grosche, Alexander G. Eaton

Abstract: The metamagnetic transition in UTe$_2$ plays a key role in stabilizing two enigmatic field-induced superconducting phases. One of these phases (SC2) is truncated by the transition, lying directly below it, while the other (SC3) sits predominantly above it and appears to be stabilized because of it. While numerous pulsed field studies have examined this transition, comparatively few steady field ex… ▽ More The metamagnetic transition in UTe$_2$ plays a key role in stabilizing two enigmatic field-induced superconducting phases. One of these phases (SC2) is truncated by the transition, lying directly below it, while the other (SC3) sits predominantly above it and appears to be stabilized because of it. While numerous pulsed field studies have examined this transition, comparatively few steady field experiments have investigated it. Here we report a suite of measurements of metamgnetism in UTe$_2$, at ambient pressure by torque magnetometry and extraction magnetometry techniques, and of the magnetoconductance under pressure. Our steady field measurements resolve a complex sub-structure within the transition, with separate features that possess different temperature evolutions, pointing to distinct contributions from itinerant and localized moments. The itinerant contribution might relate to a possible spin-density wave state. We theoretically model the evolution of Kondo and RKKY interactions and propose that the SC2 state is stabilized under pressure due to the collapse of magnetic anisotropy, leading to an enhancement of longitudinal spin fluctuations along the hard $b$ axis, which are pair-forming in the $p$-wave channel. △ Less

Submitted 26 June, 2026; originally announced June 2026.

Preparing two-mode magnonic Schrödinger cat states in a cavity-magnon-qubit system

Authors: Gen Li, Gang Liu, Rong-Can Yang, Jie Li

Abstract: The cavity-magnon-qubit system has recently been demonstrated as a new platform for preparing macroscopic quantum states in magnonic systems. Here, we propose to prepare a two-mode magnonic cat state, which is also a non-Gaussian entangled state, based on this practical system involving two yttrium-iron-garnet (YIG) spheres and a superconducting qubit coupled to a common microwave cavity. By adiab… ▽ More The cavity-magnon-qubit system has recently been demonstrated as a new platform for preparing macroscopic quantum states in magnonic systems. Here, we propose to prepare a two-mode magnonic cat state, which is also a non-Gaussian entangled state, based on this practical system involving two yttrium-iron-garnet (YIG) spheres and a superconducting qubit coupled to a common microwave cavity. By adiabatically eliminating the cavity and resonantly driving the qubit, an effective magnon-qubit conditional-displacement interaction is achieved. Further working in the magnon-magnon strong-coupling regime and considering two identical magnon frequencies and coupling strengths to the cavity, two hybridized magnon modes are formed, of which the bright mode is prepared in a cat state after a projective measurement on the qubit, while the dark mode remains in its initial vacuum state. Such a state corresponds to a two-mode cat state of two original magnon modes, which share strong non-Gaussian entanglement. We also discuss practical dissipation and dephasing effects on the cat state. The results indicate that strong nonclassicality and non-Gaussian entanglement are present in the two-mode cat state using fully feasible parameters. △ Less

Submitted 24 June, 2026; originally announced June 2026.

Formation and dynamics of self-bound droplets in dipolar molecular condensate

Authors: Xinyi Tang, Tianmiao Zhang, Zibin Zhao, Guilong Li, Zhaopin Chen, Bin Liu, Boris A. Malomed, Yongyao Li

Abstract: Recent advances in the work with ultracold condensates of polar molecules have enabled the realization of highly tunable self-bound quantum droplets (QDs), with the help of dual microwave fields dressig the dipole-dipole interactions (DDIs) It has been reported that symmetry properties and the equilibrium phase diagram of such QDs can be controlled by parameters of the two microwave fields. Howeve… ▽ More Recent advances in the work with ultracold condensates of polar molecules have enabled the realization of highly tunable self-bound quantum droplets (QDs), with the help of dual microwave fields dressig the dipole-dipole interactions (DDIs) It has been reported that symmetry properties and the equilibrium phase diagram of such QDs can be controlled by parameters of the two microwave fields. However, the effect of these fields on the formation and dynamics of the QD has not yet been systematically explored. Here we address self-bound QDs in a regime dominated by non-axisymmetric DDIs and governed by the extended Gross-Pitaevskii equation with the Lee-Huang-Yang corrections. Within this framework, we identify the existence region of the self-bound QDs and characterize their chemical potential, total energy, effective volume, peak density, and geometric anisotropy. The results reveal a pronounced nonmonotonous dependence on the non-axisymmetric DDI strength, whereas the increase of the number of particles in the condensate leads to tighter bound and more anisotropic QDs. Furthermore, reducing the s-wave scattering length drives a transition from stable self-bound states to the collapse. Collisions between QDs moving along different directions reveal a strong directional dependence, with outcomes ranging from quasi-elastic rebound and merger to fragmentation. △ Less

Submitted 21 June, 2026; originally announced June 2026.

Comments: 9 pages, 8 figures, and 66 References

Machine Learning Accelerated SSNEB for Efficient Minimum Energy Pathway Calculations

Authors: Yu Zhang, Guanzhi Li, Minkyung Han, Sean Gasiorowski, Daniel Ratner, Chunjing Jia, Yu Lin

Abstract: Metastable states and their minimum energy pathways (MEPs) are central to understanding transformations and phase stability in complex materials, yet mapping transition pathways between competing states remains computationally demanding and experimentally challenging. Here, we introduce a hybrid solid-state nudged elastic band (SSNEB) framework that integrates two pretrained machine learning model… ▽ More Metastable states and their minimum energy pathways (MEPs) are central to understanding transformations and phase stability in complex materials, yet mapping transition pathways between competing states remains computationally demanding and experimentally challenging. Here, we introduce a hybrid solid-state nudged elastic band (SSNEB) framework that integrates two pretrained machine learning models, EquiformerV2 (eqV2) and the equivariant Smooth Energy Network (eSEN), with DFT for energy, force, and stress evaluations. Applied to three solid-state systems, CsPbI$_3$, GaN, and TiO$_2$, our framework achieves up to a 7-fold speedup while converging to the same pathways predicted by first-principles calculations. Moreover, the hybrid SSNEB framework enables systematic benchmarking of existing ML models, providing both efficiency and reliability for predicting MEPs across various materials. △ Less

Submitted 11 June, 2026; originally announced June 2026.

Supermoiré Chern mosaic in helical trilayer WSe2

Authors: Zhenyu Wang, Mingjie Zhang, Hai Meng, Xiuzhen Li, Subi Du, Yaotian Liu, Siyu Fan, Xiaofan Shi, Kenji Watanabe, Takashi Taniguchi, Wei Yang, Guangyu Zhang, Bingbing Tong, Guangtong Liu, Li Lu, Jie Shen, Gang Li, Jing Song, Enke Liu, Song Liu, Fengcheng Wu, Yang Xu

Abstract: Helically twisted multilayers offer access to moiré physics beyond the single-superlattice paradigm, yet their correlated and topological transport properties remain largely unexplored in semiconductor moiré materials. Here we report magnetotransport measurements of helical trilayer WSe2, in which two coupled moiré patterns relax into a supermoiré landscape composed of inequivalent local topologic… ▽ More Helically twisted multilayers offer access to moiré physics beyond the single-superlattice paradigm, yet their correlated and topological transport properties remain largely unexplored in semiconductor moiré materials. Here we report magnetotransport measurements of helical trilayer WSe2, in which two coupled moiré patterns relax into a supermoiré landscape composed of inequivalent local topological domains with distinct electronic structures and unequal spatial areas. By electrostatic tuning, we identify a trilayer-hybridized regime where interactions and real-space reconstruction combine to generate a plethora of magnetic and topological states absent in the twisted bilayers. At moiré filling factor $ν$ = -1, we observe a ferromagnetic insulating state that is robust against magnetic field and accompanied by a non-quantized anomalous Hall response ~-4 kOhms. This behaviour is consistent with a time-reversal-symmetry-breaking supermoiré Chern mosaic, in which the Hall response arises from the non-cancelling contributions of local domains with opposite Chern character arranged by the relaxed structure. Under strong magnetic fields, a symmetry-broken Chern insulating state (C = 1) emerges near $ν$ = -2/3, displaying a much larger positive Hall response together with strongly enhanced longitudinal resistance, suggestive of field-reconstructed topological minibands and domain-boundary scattering. These results establish relaxed supermoiré semiconductor trilayers as a platform for spatially organized magnetism and topology beyond the bilayer limit. △ Less

Submitted 9 June, 2026; originally announced June 2026.

Comments: 30 pages, including 4 main figures and 10 supplemental figures

Geometric Bounds on the Finite-Time Performance of Active Machines

Authors: Geng Li, Z. C. Tu

Abstract: Optimizing energy conversion in active matter remains a central challenge in nonequilibrium physics. Here, we develop a unified thermodynamic framework that characterizes the finite-time performance of interacting active machines. We show that cyclic work admits a geometric decomposition into an antisymmetric thermodynamic curvature, governing work extraction, and a symmetric metric, controlling d… ▽ More Optimizing energy conversion in active matter remains a central challenge in nonequilibrium physics. Here, we develop a unified thermodynamic framework that characterizes the finite-time performance of interacting active machines. We show that cyclic work admits a geometric decomposition into an antisymmetric thermodynamic curvature, governing work extraction, and a symmetric metric, controlling dissipation. Minimal-dissipation protocols follow geodesics in parameter space, while optimal work extraction deviates from them due to a curvature-induced, Lorentz-like effect. This geometric structure directly determines the finite-time scaling of work and dissipation, enabling a mapping onto Onsager-type quasi-linear current--force relations. We show that both the maximal efficiency and the efficiency at maximum power are governed by an asymmetry parameter and a figure of merit, establishing a formal correspondence between active machines and thermoelectric devices with broken time-reversal symmetry. Our results reveal a fundamental geometric origin of energy-conversion performance and provide a general framework for optimizing active machines. △ Less

Submitted 9 June, 2026; v1 submitted 2 June, 2026; originally announced June 2026.

MatterSim-MT: A multi-task foundation model for in silico materials characterization

Authors: Han Yang, Xixian Liu, Chenxi Hu, Yichi Zhou, Yu Shi, Chang Liu, Junfu Tan, Jielan Li, Guanzhi Li, Qian Wang, Yu Zhu, Zekun Chen, Shuizhou Chen, Fabian Thiemann, Claudio Zeni, Matthew Horton, Robert Pinsler, Andrew Fowler, Daniel Zügner, Tian Xie, Lixin Sun, Yicheng Chen, Lingyu Kong, Yeqi Bai, Deniz Gunceler , et al. (3 additional authors not shown)

Abstract: Accurate property characterization is a major bottleneck in materials design. While first-principles methods and task-specific machine-learning models have driven important progress, they remain fundamentally limited in scalability and generalizability across the vast space of structures and properties relevant to real-world materials design. We present MatterSim-MT, a multi-task foundation model… ▽ More Accurate property characterization is a major bottleneck in materials design. While first-principles methods and task-specific machine-learning models have driven important progress, they remain fundamentally limited in scalability and generalizability across the vast space of structures and properties relevant to real-world materials design. We present MatterSim-MT, a multi-task foundation model for in silico materials simulation and property characterization. The model is pretrained on over 35 million first-principles-labeled structures covering 89 elements, temperatures up to 5000 K and pressures up to 1000 GPa, and is fine-tuned on various properties including Bader charges, magnetic moments, Born effective charges, and dielectric matrices. Out of the box, MatterSim-MT not only serves as a foundation model for predicting material structure, dynamics and thermodynamics, its multi-task architecture also enables a wide range of complex simulations that cannot be captured by potential energy surfaces alone. For example, we demonstrate pressure-dependent LO-TO phonon splitting in SiC with close agreement with experiment, electric hysteresis in ferroelectric BaTiO3, and the cationic-to-anionic redox transition during delithiation of a Li-rich cathode material. Finally, we show that MatterSim-MT scales well with more data and parameters, can be efficiently fine-tuned to higher levels of theory, and can be efficiently extended to new systems via active learning. Overall, we believe this approach provides a scalable route to accurate in silico materials characterization. △ Less

Submitted 28 May, 2026; v1 submitted 8 May, 2026; originally announced May 2026.

Macroscopic entanglement between two magnon modes via two-tone driving of a superconducting qubit

Authors: Rong-Can Yang, Gang Liu, Gen Li, Jie Li

Abstract: The cavity-mediated coupling between magnons in an yttrium-iron-garnet (YIG) sphere and a superconducting qubit has recently been demonstrated as a new platform for preparing macroscopic quantum states. Here, based on this system, we propose to entangle two magnon modes in two YIG spheres by driving the qubit with a two-tone field and by appropriately choosing the frequencies and strengths of the… ▽ More The cavity-mediated coupling between magnons in an yttrium-iron-garnet (YIG) sphere and a superconducting qubit has recently been demonstrated as a new platform for preparing macroscopic quantum states. Here, based on this system, we propose to entangle two magnon modes in two YIG spheres by driving the qubit with a two-tone field and by appropriately choosing the frequencies and strengths of the two driving fields. We show that strong entanglement can be achieved with fully feasible parameters. We further provide a detection scheme for experimentally verifying the entanglement. Our results indicate that macroscopic entanglement between two magnon modes in two millimeter-sized YIG spheres, involving more than $10^{18}$ spins, can be realized using currently available parameters, which finds promising applications in fundamental studies, such as macroscopic quantum mechanics and the test of unconventional decoherence theories. △ Less

Submitted 7 May, 2026; originally announced May 2026.

Two distinct superconducting regimes in Ti4Co2O under pressures

Authors: Lifen Shi, Keyuan Ma, Binbin Ruan, Zhen Wang, Pengtao Yang, Zhian Ren, Jianping Sun, Gang Li, Fabian O. von Rohr, Bosen Wang, Jinguang Cheng

Abstract: We report on the pressure dependence of superconducting transition temperature Tc and upper critical field Bc2(0) through electrical transport of the Ti4Co2O superconductor (eg.,the superconducting transition temperature Tc = 2.5 K and the Bc2(0)=7.2T=2.9Tc). We find that the Tc exhibits non-monotonic pressure dependence:it rises monotonically at first with a pressure coefficient of dTc/dP=0.034 K… ▽ More We report on the pressure dependence of superconducting transition temperature Tc and upper critical field Bc2(0) through electrical transport of the Ti4Co2O superconductor (eg.,the superconducting transition temperature Tc = 2.5 K and the Bc2(0)=7.2T=2.9Tc). We find that the Tc exhibits non-monotonic pressure dependence:it rises monotonically at first with a pressure coefficient of dTc/dP=0.034 K/GPa, but rapidly decreases around 10-20 GPa, and then increases with the dTc/dP = 0.023 K/GPa, up to= 4.31 K at 69.7 GPa. Concurrently, the Bc2(0)exhibits a dome shaped pressure dependence, with its maximum at 5 GPa of almost twice the value at ambient pressure, exceeding the weak-coupling Pauli paramagnetic limit Bp throughout the whole pressure range. By comparing the normal-state and superconducting properties, we identify two distinct superconducting regimes, with a low-pressure superconducting phase characterized by an enhanced Bc2(0)values and Fermi-liquid normal-state electrical transport (the exponent n = 2), and a high-pressure superconducting phase with a monotonically increased Tc and an enhancement in phonon scatterings (the exponent n = 4). Room-temperature synchrotron X-ray diffraction indicates that there is no structural transition up to 55.8 GPa, which gives a relatively large bulk modulus of 192 GPa in comparison with other alloy superconductors. First-principles calculations suggest that the nonmonotonic Tc maybe closely related to the evolution of the density of states of Ti4Co2O upon compression, which is different from those of isostructural superconductors Ti4Ir2O and Nb4Rh2C. Our results show that even in the Ti4Co2O with weak spin-orbit coupling, superconductivity remains highly sensitive to the external stimuli such as pressure. △ Less

Submitted 3 May, 2026; originally announced May 2026.

Comments: 18 pages, 6 figures

Bragg-Williams order competes with superconductivity

Authors: Xu Liu, Xu Chen, Chuizhen Chen, Boqin Song, Jing Chen, Xijing Dai, Qinghua Zhang, Feng Jin, Xingya Wang, Weiwei Dong, Dongliang Yang, Gefei Li, Pengju Zhang, Jiangping Hu, Jian-gang Guo, Tianping Ying, Xiaolong Chen

Abstract: Orderings in charge and spin have been extensively studied to unravel their correlation to emergent superconductivity over the past decades. Bragg-Williams order (BWO), a classical structural order parameter describing site occupancy in alloys, has long been speculated to influence superconducting behavior. Yet, its role still remains ambiguous, largely due to the difficulty of isolating BWO from… ▽ More Orderings in charge and spin have been extensively studied to unravel their correlation to emergent superconductivity over the past decades. Bragg-Williams order (BWO), a classical structural order parameter describing site occupancy in alloys, has long been speculated to influence superconducting behavior. Yet, its role still remains ambiguous, largely due to the difficulty of isolating BWO from concomitant charge doping or competing electronic instabilities. Here, we establish In2/3PSe3 as a platform wherein indium vacancies are reversibly configurable between ordered and disordered states via thermal treatment. We show that the disordered phase undergoes a pressure-induced superconducting transition with a Tc of 11 K, significantly higher than the 7 K observed in its ordered counterpart. This constitutes a rare instance in which pure BWO variation drives a substantial shift in Tc. By combining a Ginzburg-Landau phenomenological analysis with a BCS-McMillan microscopic description, we demonstrate that BWO naturally suppresses superconductivity through electron-phonon interactions, a mechanism supported by ultra-low-wavenumber Raman measurements. Our findings support BWO as an independent order parameter that competes directly with superconductivity, extending the concept of competing orders beyond conventional electronic and magnetic degrees of freedom. △ Less

Submitted 28 April, 2026; originally announced April 2026.

Comments: 16 pages, 14 figures

Spin Seebeck Effect in Normal-Metal--Chiral-Insulator Heterostructure

Authors: Jiayan Zhang, Gaoyang Li, Gaomin Tang, Yanxia Xing

Abstract: Phonons can carry angular momentum and exhibit chirality through the circular polarization of atomic motion. This enables a phonon-mediated spin Seebeck effect (SSE) via the conversion of phonon angular momentum into electron spin angular momentum. In this Letter, we develop a theoretical framework for calculating the spin current in a normal-metal--chiral-insulator (NM--CI) heterostructure within… ▽ More Phonons can carry angular momentum and exhibit chirality through the circular polarization of atomic motion. This enables a phonon-mediated spin Seebeck effect (SSE) via the conversion of phonon angular momentum into electron spin angular momentum. In this Letter, we develop a theoretical framework for calculating the spin current in a normal-metal--chiral-insulator (NM--CI) heterostructure within the nonequilibrium Green's function formalism. We discuss the influence of (i) the thermal bias across the NM--CI interface, (ii) the chemical potential of the NM, and (iii) the modification of the interfacial on-site potential on the spin transport properties. We identify two characteristic nonlinear spin-transport phenomena: negative differential SSE and spin-current rectification. The negative differential SSE arises from the competition between the thermal bias and the density of thermally excited electrons. Spin-current rectification suggests the possibility of realizing a thermally controlled spin diode. We also find that the spin-transport behavior is closely associated with an effective interfacial spectral density. This work suggests a novel route toward thermally controlled spintronic devices using chiral phonons. △ Less

Submitted 30 June, 2026; v1 submitted 24 April, 2026; originally announced April 2026.

Discovery of parity-violating chiral polar-nematic charge density wave and superconductivity in kagome metals

Authors: Xingwei Shi, Geng Li, Zhan Wang, Chuqi Zhang, Ke Zhu, Keyu Zeng, Zikun Tang, Li Huang, Zhen Zhao, Jianping Sun, Xiao Liu, Jin-Guang Cheng, Chengmin Shen, Shu Ping Lau, Kian Ping Loh, Haitao Yang, Xiao Lin, Ziqiang Wang, Hong-Jun Gao

Abstract: Nonmagnetic kagome metals and superconductors AV3Sb5 (A = K, Rb, Cs) host unconventional charge density wave (CDW) and superconducting (SC) phases accompanied by multiple electronic symmetry breaking. Due to the centrosymmetric crystal structure, inversion symmetry has generally been assumed to hold. Here, using scanning tunneling microscopy complemented by atomic force microscopy and optical seco… ▽ More Nonmagnetic kagome metals and superconductors AV3Sb5 (A = K, Rb, Cs) host unconventional charge density wave (CDW) and superconducting (SC) phases accompanied by multiple electronic symmetry breaking. Due to the centrosymmetric crystal structure, inversion symmetry has generally been assumed to hold. Here, using scanning tunneling microscopy complemented by atomic force microscopy and optical second-harmonic generation, we directly reveal that inversion symmetry in the kagome plane is spontaneously broken in the CDW state. The mixed-parity CDW state exhibits ferroelectric dipolar and nematic quadrupolar ordered moments. The coexistence and coupling between the dipole and quadrupole favor noncollinear ferro-polar and nematic alignment that breaks all mirror symmetries and gives rise to robust electronic chirality in the 3Q CDW. The multipolar coupling to in-plane electric field enables electric field control and manipulation of the chiral polar-nematic CDW state, including its chirality. Below the SC transition, we observe parity-violating pair density modulations at both the original and the CDW lattice wavevectors. Our findings of parity-violating electronic chiral multipolar order provide microscopic insights into the magnetoelectric and nonreciprocal transport, loop current order, pairing density waves, and unconventional superconductivity in kagome metals and related quantum materials. △ Less

Submitted 22 April, 2026; originally announced April 2026.

Atomic-scale origin of charge density wave-driven metal-semiconductor transition in an incommensurately modulated metal-organic framework

Authors: Ling Zhang, Zeyue Zhang, Liu He, Bin Jiang, Yingchao Wang, Jiaxiang Zhang, Huimin Qi, Chao Zhang, Jinkun Guo, Hao Chen, Yunlong Fan, Yanran Shen, Hongli Jia, Guobao Li, Yu-Qing Zheng, Julius J. Oppenheim, Tianyang Chen, Jian Wang, Lei Sun, Junliang Sun, Jin-Hu Dou

Abstract: The intrinsic incommensurate charge density wave in metal-organic frameworks has remained elusive due to the lack of direct evidence linking atomic-scale structural modulation to macroscopic electronic properties. Using high-quality Pr3HHTP2 (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) single crystals as a model system, we precisely resolve, for the first time, the incommensurately modulated str… ▽ More The intrinsic incommensurate charge density wave in metal-organic frameworks has remained elusive due to the lack of direct evidence linking atomic-scale structural modulation to macroscopic electronic properties. Using high-quality Pr3HHTP2 (HHTP = 2,3,6,7,10,11-hexahydroxytriphenylene) single crystals as a model system, we precisely resolve, for the first time, the incommensurately modulated structure of a conductive metal-organic framework at 100 K (modulation vector q = 0.39143(12) c*) via temperature-dependent single-crystal X-ray diffraction. The subsequent observation of a reversible metal-semiconductor transition around 350 K, which perfectly synchronizes with the disappearance of the structural modulation, provides convincing evidence for the electronic origin of the lattice distortion. Guest water molecules stabilize the modulated phase by synergistically regulating the relative rotation of the linkers and the interlayer spacing, thereby optimizing the inter-linker interactions. This work establishes a concrete experimental criterion for one-dimensional charge density wave in metal-organic frameworks and provides an ideal platform for probing coupled electronic-lattice modulations. △ Less

Submitted 21 April, 2026; originally announced April 2026.

Shortcuts to state transitions for active matter

Authors: Guodong Cheng, Z. C. Tu, Geng Li

Abstract: Shortcut schemes can accelerate quasi-static processes in passive systems by adding auxiliary controls to realize swift transitions between equilibrium states. In active systems, however, inherently directed motion driven by free energy consumption continually drives the system away from equilibrium. In this work, we develop a shortcut framework to realize swift state transitions for active system… ▽ More Shortcut schemes can accelerate quasi-static processes in passive systems by adding auxiliary controls to realize swift transitions between equilibrium states. In active systems, however, inherently directed motion driven by free energy consumption continually drives the system away from equilibrium. In this work, we develop a shortcut framework to realize swift state transitions for active systems operating in the weak activity regime. An auxiliary potential is introduced to guide the system along a predefined distribution path, allowing it to reach the target state within a finite time. Considering unavoidable energy cost in such a finite-time process, we derive a thermodynamic metric from the dissipative work to induce a Riemann manifold on the space spanned by the control parameters. The optimal protocol with minimum dissipative work is then identical to the geodesic path in the geometric space. We demonstrate this framework by considering active systems confined in an external harmonic trap and interacting via two distinct internal potentials, respectively: an attractive harmonic coupling and a repulsive pairwise Gaussian-core coupling. The strengths of both the external trap and the internal interactions are controllable. For the latter case, since the auxiliary potential can not be derived precisely, we adopt a variational method to obtain an approximate auxiliary control. Compared to linear protocols, the geodesic protocols can effectively reduce dissipation. △ Less

Submitted 7 April, 2026; originally announced April 2026.

Cs$_3$V$_9$Te$_{13}$: A Correlated Electron System with Topological Flat Bands

Authors: Chang-Chao Liu, Ji-Yong Liu, Jing Li, Hua-Xun Li, Jia-Yi Lu, Tong Shi, Qing-Xin Dong, Gen Li, Bo-Sen Wang, Yi Liu, Jin-Guang Cheng, Guang-Han Cao

Abstract: Correlated electron systems with topological flat bands show great promise in exploring exotic quantum phenomena. However, such crystalline materials remain rare. Here we report the discovery of a novel material, Cs$_3$V$_9$Te$_{13}$, which unexpectedly exhibits magnetism and significant electron correlations. The crystal structure features two interpenetrating sets of vanadium triangles that can… ▽ More Correlated electron systems with topological flat bands show great promise in exploring exotic quantum phenomena. However, such crystalline materials remain rare. Here we report the discovery of a novel material, Cs$_3$V$_9$Te$_{13}$, which unexpectedly exhibits magnetism and significant electron correlations. The crystal structure features two interpenetrating sets of vanadium triangles that can be linked with an ideal kagome lattice. The physical property measurements demonstrate a cascade of correlated electron phenomena, including quasi-two-dimensional bad metal, non-Fermi-liquid behavior, antiferromagnetic spin-density-wave transition at $T_\mathrm{N}$ = 47 K, possible short-range spin ordering at $\sim$350 K, a large Sommerfeld coefficient of 246 mJ mol-fu$^{-1}$ K$^{-2}$, and pressure-induced quantum criticality. These correlated electron behaviors are associated with the topological flat bands at the Fermi level, the latter of which are generated from the V2 sublattice in terms of a bipartite kagome model. Our findings establish Cs$_3$V$_9$Te$_{13}$ as a brand new correlated matter that synergistically combines flat-band physics and tunable properties. △ Less

Submitted 29 March, 2026; originally announced March 2026.

Comments: 23 pages, 9 figures, 2 tables

Lattice-Expansion-Driven Stabilization of Helical Magnetic Order in Ru-Doped MnP

Authors: Xin-Wei Wu, Deng-lu Hou, Li Ma, Cong-mian Zhen, De-wei Zhao, Guoke Li

Abstract: The practical utilization of MnP in chiral spintronic devices is fundamentally constrained by its low helical ordering temperature ($T_{\rm S}$). Here, we demonstrate that Ru substitution in Mn$_{1-x}$Ru$_x$P single crystals drives a highly anisotropic lattice expansion, where the $b$-axis elongation is one-quarter that of the $a$- and $c$-axes ($\sim$ 0.04 Å). This structural distortion profoundl… ▽ More The practical utilization of MnP in chiral spintronic devices is fundamentally constrained by its low helical ordering temperature ($T_{\rm S}$). Here, we demonstrate that Ru substitution in Mn$_{1-x}$Ru$_x$P single crystals drives a highly anisotropic lattice expansion, where the $b$-axis elongation is one-quarter that of the $a$- and $c$-axes ($\sim$ 0.04 Å). This structural distortion profoundly stabilizes the helical ground state, elevating $T_{\rm S}$ from 51~K to 215~K and the critical field along the [010] direction at 5~K from 2.3 to 30.0~kOe, while suppressing the Curie temperature ($T_{\rm C}$) from 291~K to 215~K. Synthesizing these results with reported data on Mo- and W-doped analogues reveals that $T_{\rm S}$ and $T_{\rm C}$ are governed primarily by the $b$-axis parameter, exhibiting universal linear scaling relationships ($dT_{\rm S}/db = 1.59 \times 10^4\ \text{KÅ}^{-1}$, $dT_{\rm C}/db = 0.69 \times 10^4\ \text{KÅ}^{-1}$) far greater than those associated with the $a$- or $c$-axes. First-principles calculations reveal that the lattice expansion selectively attenuates ferromagnetic coupling while preserving antiferromagnetic interactions between nearest-neighbor Mn atoms, thereby enhancing magnetic frustration and stabilizing helimagnetism. These findings establish chemical pressure via directed $b$-axis engineering as a robust, generalizable paradigm for stabilizing helimagnetism in MnP. △ Less

Submitted 25 March, 2026; originally announced March 2026.

Mn substitution induced a ferrimagnetic to ferromagnetic transition in trigonal $\text{Cr}_5\text{Te}_8$

Authors: Ze-Xin Liu, Yu Liu, Sen-Miao Zhao, De-Wei Zhao, Li Ma, Deng-Lu Hou, Guo-Ke Li

Abstract: Tailoring the magnetic properties of chromium tellurides via heterointercalation with extrinsic transition metals remains largely unexplored. Here, we report a comprehensive investigation of trigonal Cr$_5$Te$_8$ and Cr$_4$MnTe$_8$ single crystals, in which Mn substitution elevates the magnetic ordering temperature from 226 to 249 K and enhances the saturation magnetic moment per magnetic ion (… ▽ More Tailoring the magnetic properties of chromium tellurides via heterointercalation with extrinsic transition metals remains largely unexplored. Here, we report a comprehensive investigation of trigonal Cr$_5$Te$_8$ and Cr$_4$MnTe$_8$ single crystals, in which Mn substitution elevates the magnetic ordering temperature from 226 to 249 K and enhances the saturation magnetic moment per magnetic ion ($m_{\text{S}}$) from 2.00 to 2.66 $μ_{\text{B}}$ at 5 K. Remarkably, the observed $m_{\text{S}}$ enhancement significantly exceeds the contribution of Mn ion moments alone, indicating the relief of intrinsic spin compensation within the parent lattice. First-principles calculations definitively establish that pristine $\text{Cr}_5\text{Te}_8$ exhibits ferrimagnetic ordering with a computed $m_\text{S}$ of 1.98~$μ_\text{B}$, and further reveal that preferential occupation of the van der Waals gaps by Mn ions induces a ferrimagnetic-to-ferromagnetic transition, yielding a predicted $m_\text{S}$ of 2.94~$μ_\text{B}$. These findings not only resolve the magnetic ground state of trigonal Cr$_5$Te$_8$ but also identify heterointercalation as a robust strategy for engineering the spin textures of chromium tellurides. △ Less

Submitted 27 April, 2026; v1 submitted 25 March, 2026; originally announced March 2026.

Tunable intersublattice exchange coupling drives magnetic evolution in Mn$_{3+x}$Ga$_{1-x}$C ($0 \le x \le 0.60$)

Authors: Dong-Hui Xu, Cong-Mian Zhen, Deng-Lu Hou, Li Ma, De-Wei Zhao, Guo-ke Li

Abstract: We investigate the magnetic and transport evolution in Mn$_{3+x}$Ga$_{1-x}$C ($0 \le x \le 0.60$), where Mn substitution at corner Ga sites induces lattice contraction and suppresses the antiferromagnetic order of Mn$_3$GaC. As $x$ increases, the magnetic ground state of the system undergoes a sequential transition from an antiferromagnetic state, via a canted ferrimagnetic state, to a robust ferr… ▽ More We investigate the magnetic and transport evolution in Mn$_{3+x}$Ga$_{1-x}$C ($0 \le x \le 0.60$), where Mn substitution at corner Ga sites induces lattice contraction and suppresses the antiferromagnetic order of Mn$_3$GaC. As $x$ increases, the magnetic ground state of the system undergoes a sequential transition from an antiferromagnetic state, via a canted ferrimagnetic state, to a robust ferrimagnetic state, accompanied by a surge in the magnetic ordering temperature. Saturation magnetic moments reaches a maximum of 3.63~$μ_{\mathrm{B}}$/f.u. at $x = 0.10$, whereas the topological Hall resistivity peaks at 1.47~$μΩ\cdot$cm for $x = 0.20$ before decreasing with further doping. First-principles calculations demonstrate a $\sim\!40^{\circ}$ canting of face-centered Mn moments at $x = 0.20$, signifying spin frustration, and an eventual antiparallel alignment of face-centered and corner-site Mn moments at higher $x$. These results reveal that intersublattice antiferromagnetic coupling governs the magnetic transformation and emergent transport phenomena, thus providing a microscopic foundation for designing high-ordering-temperature antiperovskites. △ Less

Submitted 25 March, 2026; originally announced March 2026.

Coupling of phase transition, anharmonicity, and thermal transport in CaSnF$_6$

Authors: Daxue Hao, Hao Huang, Geng Li, Yu Wu, Shuming Zeng

Abstract: Understanding the coupling between structural phase transitions and thermal transport is essential for designing functional materials with tunable properties. Here, we investigate this interplay in CaSnF$_6$ by combining first-principles calculations with a machine-learned neuroevolution potential that enables large-scale molecular dynamics simulations across a wide temperature range. The simulati… ▽ More Understanding the coupling between structural phase transitions and thermal transport is essential for designing functional materials with tunable properties. Here, we investigate this interplay in CaSnF$_6$ by combining first-principles calculations with a machine-learned neuroevolution potential that enables large-scale molecular dynamics simulations across a wide temperature range. The simulations accurately capture the first-order structural phase transition and associated lattice dynamics. We show that the negative thermal expansion originates from low-energy rigid unit modes involving cooperative rotations of corner-sharing [CaF$_6$]$^{4-}$ octahedra, which induce bond-angle bending and volume contraction. At the same time, strong anharmonicity, dominated by four-phonon scattering, plays a central role in suppressing lattice thermal conductivity ($κ_L$). Crucially, non-equilibrium simulations reveal a pronounced non-monotonic anomaly in $κ_L$ near the phase transition, deviating from the conventional $\sim 1/T^α$ behavior and providing direct transport evidence of lattice reconstruction. These results establish a unified mechanism linking lattice geometry, anharmonic vibrational dynamics, and thermal transport, and highlight the potential of machine-learned potentials for bridging atomic-scale phase transitions with macroscopic transport properties. △ Less

Submitted 13 April, 2026; v1 submitted 24 March, 2026; originally announced March 2026.

Observation of Resonance of Kagome Flat Band Doublet

Authors: Renjie Zhang, Bei Jiang, Xiangqi Liu, Hengxin Tan, Xuefeng Zhang, Mojun Pan, Quanxin Hu, Yiwei Cheng, Chengnuo Meng, Yudong Hu, Yufan Zhao, Runze Wang, Dupeng Zhang, Junqin Li, Zhengtai Liu, Mao Ye, Ziqiang Wang, Yaobo Huang, Gang Li, Yanfeng Guo, Hong Ding, Baiqing Lv

Abstract: The interplay between local and itinerant electrons underpins many correlated and topological quantum states. Kagome lattices provide an ideal platform by hosting both flat (localized states) and dispersive bands (itinerant states), yet direct spectroscopic evidence of their dynamical coupling has remained elusive. Here we report the long-sought flat band resonance in the quasi-two-dimensional kag… ▽ More The interplay between local and itinerant electrons underpins many correlated and topological quantum states. Kagome lattices provide an ideal platform by hosting both flat (localized states) and dispersive bands (itinerant states), yet direct spectroscopic evidence of their dynamical coupling has remained elusive. Here we report the long-sought flat band resonance in the quasi-two-dimensional kagome bilayer material CsCr6Sb6. Using angle-resolved photoemission spectroscopy, transport measurements, and combined density functional theory and dynamical mean-field theory, we identify coexisting flat band doublets and dispersive bands near the Fermi energy. Upon cooling, the flat and dispersive bands exhibit a pronounced enhancement of spectral weight and hybridization, directly evidencing flat band resonance. Crucially, this emergence coincides with the onset of short-range antiferromagnetic correlations, contrasting sharply with conventional Kondo lattice behavior. Our findings demonstrate not only the long-sought flat band resonance in kagome materials, but also its unconventional correlation with magnetism. △ Less

Submitted 19 March, 2026; originally announced March 2026.

Comments: accepted by Nature Communications

Journal ref: Nature Communications 17, 4013 (2026)

Site-selective renormalization and competing magnetic instabilities in paramagnet Y$_{3}$Cu$_{2}$Sb$_{3}$O$_{14}$

Authors: Yanpeng Zhou, Gang Li

Abstract: Quantum spin liquids (QSLs) are exotic phases of matter characterized by long-range entanglement and the absence of magnetic order even at zero temperature. Here, we present a comprehensive theoretical study of the frustrated magnet Y$_3$Cu$_2$Sb$_3$O$_{14}$ to elucidate its electronic and magnetic properties. We uncover completely opposite crystal-field splittings of the two inequivalent Cu sites… ▽ More Quantum spin liquids (QSLs) are exotic phases of matter characterized by long-range entanglement and the absence of magnetic order even at zero temperature. Here, we present a comprehensive theoretical study of the frustrated magnet Y$_3$Cu$_2$Sb$_3$O$_{14}$ to elucidate its electronic and magnetic properties. We uncover completely opposite crystal-field splittings of the two inequivalent Cu sites owing to their fundamentally distinct oxygen coordination - trigonal distorted octahedral CuO$_6$ and axially compressed CuO$_8$. This inversion places the unpaired hole in the $d_{z^2}$ orbital at the Cu-2 site, while Cu-1 maintains conventional $d_{x^2-y^2}/d_{xy}$ character, which results in a selective band-renormalization of orbitals from the two Cu ions. We further find multiple magnetic instabilities competing with nearly equal strength in this system: the spin susceptibility lacks dominant peaks, and the leading eigenvalues approach unity simultaneously across all wavevectors with increasing interactions. This competitive interplay, originating from the distinct local environments and geometric frustration on the triangular lattice, agrees well with the absence of long-range magnetic order in experiment. Our results support Y$_3$Cu$_2$Sb$_3$O$_{14}$ as a promising QSL candidate where the unique combination of disparate crystal-field environments, strong correlations, and competing exchange interactions conspire to stabilize an exotic quantum ground state. △ Less

Submitted 19 March, 2026; v1 submitted 18 March, 2026; originally announced March 2026.

Comments: 3 figures, 9 pages. Important reference updates and inconsistency fixes

Scalar Spin Chiral Order via Bond Selectivity in Strained Collinear Ferrimagnets

Authors: Xin Liu, Li Ma, Mingyue Zhao, Shun Niu, Yu Liu, Yang Li, Jiayao Zhu, Yiwen Zhang, Fengxian Ma, Dewei Zhao, Guoke Li, Congmian Zhen, Denglu Hou

Abstract: Scalar spin chirality (SSC) drives a series of topological transports in noncoplanar magnets. However, the ordering temperature of magnet hosting intrinsic SSC order is typically below 100 K. Current approaches to achieve near room temperature SSC order largely rely on external fields or chemical doping in noncollinear magnets. A significant challenge persists in generating and controlling SSC ord… ▽ More Scalar spin chirality (SSC) drives a series of topological transports in noncoplanar magnets. However, the ordering temperature of magnet hosting intrinsic SSC order is typically below 100 K. Current approaches to achieve near room temperature SSC order largely rely on external fields or chemical doping in noncollinear magnets. A significant challenge persists in generating and controlling SSC order in high temperature collinear magnets. Here, using the collinear ferrimagnet Mn4N with Neel temperature ~740 K as a platform, we demonstrate that isotropic strain acts as a clean and continuous tuning parameter to induce long range SSC order by first principles calculations. As strain increases from to, the magnetic ground state evolves continuously from a collinear to a noncoplanar configuration, activating the SSC order and enhancing its magnitude from 0 to ~2.32. Our quantitative orbital-resolved bonding analysis reveals that strain selectively suppresses the bond between Mn 3d orbitals and N 2p orbitals, driving dual prerequisites for the SSC order. Specifically, the decreased covalent spin-pairing activates Mn3c moments within the plane, simultaneously the suppressed N-mediated ferromagnetic superexchange interaction shifts the balance of the nearest-neighbor Mn3c sites toward antiferromagnetic exchange interaction. Our findings establish a powerful strain mediated route to construct the SSC order in high temperature collinear magnets. △ Less

Submitted 16 March, 2026; originally announced March 2026.

Giant Full-Space Anomalous Hall Effect Induced by Non-Coplanar Spin State in Mn-Rich Mn3Sn

Authors: Yiming Liu, Xin Liu, Jiayao Zhu, Fengxian Ma, Li Ma, Dewei Zhao, Guoke Li, Congmian Zhen, Denglu Hou

Abstract: Antiferromagnets are promising candidates for next-generation spintronic devices owing to their negligible stray fields and ultrafast spin dynamics. The noncollinear antiferromagnet $\mathrm{Mn}_{3}\mathrm{Sn}$ exhibits a large anomalous Hall effect (AHE). However, its specific noncollinear spin configuration leads to the forbiddance of the anomalous Hall conductivity from the (0001) basal plane,… ▽ More Antiferromagnets are promising candidates for next-generation spintronic devices owing to their negligible stray fields and ultrafast spin dynamics. The noncollinear antiferromagnet $\mathrm{Mn}_{3}\mathrm{Sn}$ exhibits a large anomalous Hall effect (AHE). However, its specific noncollinear spin configuration leads to the forbiddance of the anomalous Hall conductivity from the (0001) basal plane, $σ_{(0001)}$, limiting practical applications. Here, using first-principles density functional theory, we demonstrate that Mn enrichment in $\mathrm{Mn}_{3}\mathrm{Sn}$ drives a magnetic transition from the coplanar $120^\circ$ spin configuration to a non-coplanar state with moments tilted toward the $c$-axis. This transition is primarily mediated by four-spin ring exchange interaction in the local triangular lattice, which breaks the time-reversal symmetry and generates a giant intrinsic anomalous Hall conductivity over the full three-dimensional space in $\mathrm{Mn}_{3}\mathrm{Sn}$. We predict that $σ_{(0001)}$ reaches as high as $\sim\!-468~Ω^{-1}\cdot\mathrm{cm}^{-1}$, and an enhanced $σ_{(01\bar{1}0)}$ of $\sim\!-229~Ω^{-1}\cdot\mathrm{cm}^{-1}$ is expected in light Mn self-doping of $\mathrm{Mn}_{3}\mathrm{Sn}$ ($\mathrm{Mn}_{3.125}\mathrm{Sn}_{0.875}$). Unlike previously reported mechanisms relying on external magnetic fields or strain, our approach exploits intrinsic compositional tuning to stabilize a non-coplanar magnetic ground state for realizing a strong full-space AHE in antiferromagnets, providing another viable pathway toward high-performance, low-power spintronic devices. △ Less

Submitted 13 March, 2026; originally announced March 2026.

Comments: 16 pages, 5 figures

Electrically-controllable superconducting memory effect in UTe2

Authors: Zheyu Wu, Hanyi Chen, Mengmeng Long, Daniel Shaffer, Dmitry V. Chichinadze, Andrej Cabala, Theodore I. Weinberger, Alexander J. Hickey, Jinxu Pu, Dave Graf, Vladimir Sechovsky, Michal Valiska, Gang Li, Rui Zhou, F. Malte Grosche, Alexander G. Eaton

Abstract: If a computer could be assembled from superconducting components, the energy efficiency would far surpass that of conventional electronics. Historic research efforts towards this goal yielded pivotal breakthroughs in the development and discovery of scanning tunnelling microscopy and high temperature superconductivity. Although recent strides have been taken in advancing superconducting diode and… ▽ More If a computer could be assembled from superconducting components, the energy efficiency would far surpass that of conventional electronics. Historic research efforts towards this goal yielded pivotal breakthroughs in the development and discovery of scanning tunnelling microscopy and high temperature superconductivity. Although recent strides have been taken in advancing superconducting diode and switching technologies, harnessing read/writeable memory functionality in superconducting platforms has remained challenging. Here we show that bulk single crystal specimens of the triplet superconductor candidate uranium ditelluride (UTe$_2$) possess such properties. Upon applying a magnetic field to access an intermediate regime straddling two distinct superconducting phases, we find that direct current pulses can push the material in and out of a metastable state possessing an enhanced critical current $J_c$. This switching is controllable by the strength and duration of the stimuli, with the system `remembering' whether it is in the high or low $J_c$ state for extended periods. We interpret this to be due to competition between two distinct vortex species, which can be perturbatively pushed into a non-equilibrium high-disorder configuration with stronger pinning forces and thus higher $J_c$. Rather than requiring proximate magnetic or semiconducting interfaces, this memory functionality appears to be an intrinsic property of UTe$_2$ rooted in the superconducting order itself. Our findings underscore the rich complexity of quantum vortex matter, and demonstrate the viability of engineering a new class of superconducting memory elements with ultralow-power switching. △ Less

Submitted 1 May, 2026; v1 submitted 2 March, 2026; originally announced March 2026.

Double-Carrier Fitting of Hall Resistance Assisted by Gate-Induced Shubnikov-de Haas Oscillations in Possible Excitonic Insulator Ta2Pd3Te5

Authors: Xing-Chen Guo, An-Qi Wang, Xiu-Tong Deng, Yu-Peng Li, Guo-An Li, Zhi-Yuan Zhang, Xiao-Fan Shi, Xiao Deng, Zi-Wei Dou, Guang-Tong Liu, Fan-Ming Qu, Jie Shen, Li Lu, Zhi-Jun Wang, You-Guo Shi, Hang Li, Tian Qian

Abstract: Hall effect is an important phenomenon when a magnetic field is applied to materials. From the curve depicting the Hall resistance versus the magnetic field, crucial information such as carrier concentration can be extracted. If the curve exhibits a linear dependence up to rather high magnetic fields, it indicates that charge transport involves only a single type of carrier, and if a non-linear cu… ▽ More Hall effect is an important phenomenon when a magnetic field is applied to materials. From the curve depicting the Hall resistance versus the magnetic field, crucial information such as carrier concentration can be extracted. If the curve exhibits a linear dependence up to rather high magnetic fields, it indicates that charge transport involves only a single type of carrier, and if a non-linear curve is measured, then the double-carrier model should be considered for fitting. However, this model involves four unknown parameters, including the concentration and mobility of the two carriers, resulting in that such fitting is usually non-unique, which significantly reduces the reliability and accuracy. In this work, a double-carrier platform was constructed on a probable excitonic insulator Ta2Pd3Te5, and the four-parameter fitting based on the double-carrier model was simplified to a single-parameter fitting by employing methods such as analyzing the shape of the Hall resistance curve and generating gate-induced Shubnikov-de Haas oscillations. Thus, we provide a reliable method for double-carrier fitting of Hall resistance and a new evidence for the existence of excitonic-insulator state in Ta2Pd3Te5. △ Less

Submitted 26 February, 2026; originally announced February 2026.

Charged moments and symmetry-resolved entanglement from Ballistic Fluctuation Theory

Authors: Giorgio Li, Léonce Dupays, Paola Ruggiero

Abstract: The charged moments of a reduced density matrix provide a natural starting point for deriving symmetry-resolved Rényi and entanglement entropies, which quantify how entanglement is distributed among symmetry sectors in the presence of a global internal symmetry in a quantum many-body system. In this work, we study charged moments within the framework of Ballistic Fluctuation Theory (BFT). This the… ▽ More The charged moments of a reduced density matrix provide a natural starting point for deriving symmetry-resolved Rényi and entanglement entropies, which quantify how entanglement is distributed among symmetry sectors in the presence of a global internal symmetry in a quantum many-body system. In this work, we study charged moments within the framework of Ballistic Fluctuation Theory (BFT). This theory describes large-scale ballistic fluctuations of conserved charges and associated currents and, by exploiting the height-field formulation of twist fields, gives access to the asymptotic behaviour of their two-point correlation functions. In Del Vecchio Del Vecchio et al. $[1]$, this approach was applied to the special case of branch-point twist fields used to compute entanglement entropies within the replica approach. Here, we extend those results by applying BFT to composite branch-point twist fields, obtained by inserting an additional gauge field. Focusing on free fermions, we derive analytic expressions for charged Rényi entropies both at equilibrium, in generalized Gibbs ensembles, and out of equilibrium following a quantum quench from $U(1)$ preserving pair producing integrable initial states. In the latter case, our results agree with the conjecture arising from the quasiparticle picture. △ Less

Submitted 12 February, 2026; originally announced February 2026.

Comments: 36 pages

Realization of a Wigner-Mott insulator in 6R-TaS$_2$ superconductor

Authors: Hongqin Xiao, Geng Li, Yuxuan He, Ke Zhu, Yuhan Ye, Yumeng Li, Lijing Huang, Pucen Xiong, Haitao Yang, Ziqiang Wang, Hong-Jun Gao

Abstract: Wigner-Mott insulating states represent a paradigmatic manifestation of strong electronic correlations, in which long-range Coulomb interactions drive spontaneous charge ordering and enable Mott localization at fractional electronic fillings. Such states have been theoretically proposed to arise from the cooperative interplay between onsite and inter-site Coulomb interactions. However, experimenta… ▽ More Wigner-Mott insulating states represent a paradigmatic manifestation of strong electronic correlations, in which long-range Coulomb interactions drive spontaneous charge ordering and enable Mott localization at fractional electronic fillings. Such states have been theoretically proposed to arise from the cooperative interplay between onsite and inter-site Coulomb interactions. However, experimental realizations of the simultaneous microscopic observation of interaction-driven charge order and genuine Mott localization, which are the defining hallmarks of a Wigner-Mott insulator, have remained elusive. Here we report the observation of a Wigner-Mott insulating state in 6R-TaS$_2$ using scanning tunneling microscopy. By locally injecting electrons into the depleted 1T layer, we induce distinct Star-of-David charge-ordered superstructures and realize a cascade of insulating phases. In particular, a $\sqrt{3}\times \sqrt{3}$ charge-ordered superstructure at one-third filling hosts a robust Mott gap despite fractional filling. The spontaneous relaxation from excited states back to the ground state demonstrates that this Wigner-Mott phase is stabilized by the cooperative effects of onsite and inter-site Coulomb interactions. Our results provide direct microscopic evidence for a Wigner-Mott mechanism and establish 6R-TaS$_2$ as a platform for the controlled realization and investigation of Wigner-Mott insulating states. △ Less

Submitted 4 February, 2026; v1 submitted 27 January, 2026; originally announced January 2026.

Density of States of Ru3 and Pt3 Clusters Supported on Sputter-Deposited TiO2

Authors: Liam Howard-Fabretto, Timothy J. Gorey, Guangjing Li, Siriluck Tesana, Gregory F. Metha, Scott L. Anderson, Gunther G. Andersson

Abstract: In this work, 3-atom clusters, Ru3 and Pt3, were deposited onto radio frequency RF-sputter deposited TiO2, treated with Ar+ ion sputtering. Ru3 was deposited by both solution submersion and chemical vapor deposition of Ru3(CO)12, while Pt3 was deposited under ultra-high vacuum using a laser vaporisation cluster source. The valence electronic density of states (DOS) of the deposited clusters were a… ▽ More In this work, 3-atom clusters, Ru3 and Pt3, were deposited onto radio frequency RF-sputter deposited TiO2, treated with Ar+ ion sputtering. Ru3 was deposited by both solution submersion and chemical vapor deposition of Ru3(CO)12, while Pt3 was deposited under ultra-high vacuum using a laser vaporisation cluster source. The valence electronic density of states (DOS) of the deposited clusters were analysed after heat treatment using ultraviolet photoelectron spectroscopy (UPS) and metastable impact electron spectroscopy (MIES), where UPS measures the top several layers while MIES measures only the top atomic layer. XPS was used to determine the cluster surface coverages. The DOS were found to be very similar between Ru3 deposited by solution submersion and chemical vapor deposition. MIES results for Ru3 had contributions from titania O 2p sites due to encapsulation by a reduced titania overlayer. For Pt3 clusters the UPS and MIES results provided evidence that Pt was present on the topmost layer, and encapsulation did not occur. The proposed reason for the encapsulation of Ru3 but not of Pt3 is the higher surface energy of Ru over Pt. It is concluded that Pt clusters deposited onto TiO2 can modify the outermost layer by adding discrete energy levels on the surface, whereas the Ru clusters being encapsulated just below the surface generate a broad distribution of energy states close to the Fermi level. The outcome of this work is that Pt3-cluster-modified surfaces could be used as catalysts for reactions where the Pt3 energy levels are suitable for the respective reaction. The implication of the DOS found for photocatalytic water splitting are discussed. △ Less

Submitted 15 January, 2026; originally announced January 2026.

Comments: 43 pages, 13 Figures

Charge disproportionation as a possible mechanism towards polar antiferromagnetic metal in molecular orbital crystal

Authors: Yang Shen, Shuai Qu, Gang Li, Pu Yu, Guang-Ming Zhang

Abstract: Polar antiferromagnetic metals have recently garnered increasing interests due to their combined traits of both ferromagnets and antiferromagnets for spintronic applications. However, the inherently incompatible nature of antiferromagnet, metallicity and polarity pose a significant challenge. We propose that charge disproportionation can lead to this novel state in negative charge transfer gap reg… ▽ More Polar antiferromagnetic metals have recently garnered increasing interests due to their combined traits of both ferromagnets and antiferromagnets for spintronic applications. However, the inherently incompatible nature of antiferromagnet, metallicity and polarity pose a significant challenge. We propose that charge disproportionation can lead to this novel state in negative charge transfer gap regime in molecular orbital crystal by molecular orbital analyses of first-principles DFT+$U$ electronic band structure for representative Ruddlesden-Popper bilayer perovskite oxides Sr$_3$Co$_2$O$_7$, corroborated by Density Matrix Renormalization Group calculation. Due to the negative charge transfer nature of Co$^{4+}$ and imposed by strong interlayer coupling, localized molecular orbitals stemming from the hybridization of Co $d_{z^2}$ and $d_{xz/yz}$ orbitals through the apical oxygen $p$ orbitals are preferably emergent within each bilayer unit, which develop antiferromagnetic ordering by invoking Hubbard repulsion. Charge disproportionation driven by Hund's physics, makes an occupation imbalance with broken inversion symmetry in the remaining $d_{xy}$ and $d_{x^2-y^2}$ orbitals from distinct Co atoms within the bilayer unit, resulting in the polar metallicity. Meanwhile, this charge disproportionation scenario allows consequent conducting carriers to couple with interlayer local spins via Hund's coupling, giving rise to in-plane double-exchange ferromagnetism. Our molecular orbital formulation further provides a guide towards an effective Hamiltonian for modelling the unconventional synergy of metallicity, polarity and antiferromagnetism in Sr$_3$Co$_2$O$_7$, which may be a unified framework widely applicable to double-layer Ruddlesden-Popper perovskite oxides. △ Less

Submitted 5 January, 2026; originally announced January 2026.

Comments: 7 pages, 5 figures

Journal ref: Physical Review B 114, 034407 (2026)

Multiple nodal superconducting phases and order-parameter evolution in pressurized UTe$_2$

Authors: Shuo Zou, Fengrui Shi, Zhuolun Qiu, Jialong Zhang, Yan Zhang, Weilong Qiu, Zhuo Wang, Hai Zeng, Yinina Ma, Zheyu Wu, Andrej Cabala, Michal Valiska, Ning Li, Zihan Yang, Kaixin Ye, Jiawen Zhang, Yanan Zhang, Kangjian Luo, Binbin Zhang, Alexander G. Eaton, Chaofan Zhang, Gang Li, Jianlin Luo, Wen Huang, Huiqiu Yuan , et al. (2 additional authors not shown)

Abstract: Spin-triplet superconductivity (SC) offers a unique avenue for realizing non-Abelian Majorana zero modes and thus the fault-tolerant topological quantum computation, and has attracted a broad audience for both fundamental research and potential applications. The recently discovered heavy-fermion spin-triplet superconductor candidate UTe$_2$ has sparked great interest for its ultrahigh upper critic… ▽ More Spin-triplet superconductivity (SC) offers a unique avenue for realizing non-Abelian Majorana zero modes and thus the fault-tolerant topological quantum computation, and has attracted a broad audience for both fundamental research and potential applications. The recently discovered heavy-fermion spin-triplet superconductor candidate UTe$_2$ has sparked great interest for its ultrahigh upper critical field and reentrant SC phases in the proximity to a field-polarized magnetic state. Despite extensive studies on the phase diagrams and competing orders induced by pressure and magnetic field, limited has been known about its SC order parameters and their evolution with these control parameters, largely due to the lack of appropriate symmetry-sensitive detections. Here, we report comprehensive point-contact spectroscopy measurements of pressurized UTe$_2$ on the (0~0~1) surface. The observation of Andreev bound state strongly suggests the presence of a $p_z$ component in the SC order parameters. Quantitative analysis based on an extended Blonder-Tinkham-Klapwijk model unveils $B_{2u}$ or $B_{3u}$ as the most likely representation for both ambient and pressurized UTe$_2$, and remarkably, the multiple SC phases can be distinguished by a single parameter $\langle Δ_{z}\rangle/\langleΔ_{x(y)}\rangle$, the relative weight between the $p_z$-wave and $p_{x(y)}$-wave pairings. These findings not only impose stringent constraints on the superconducting order parameter in UTe$_2$, but also provide key spectroscopic evidence for the existence of multiple SC phases tuned through pressure. △ Less

Submitted 5 January, 2026; originally announced January 2026.

Comments: 21+14 pages, 5+9 figures, 1+1 tables

Magnetism and Correlated Electrons in LaCr$_2$Ge$_2$N

Authors: Jiao-Jiao Meng, Yu-Sen Xiao, Gen Li, Shao-Hua Liu, Bai-Zhuo Li, Hao Jiang, Zhen Yu, Yi-Qiang Lin, Xin-Yu Zhao, Qing-Chen Duan, Wu-Zhang Yang, Chong-Yao Zhao, Zhi Ren, Yu-Xue Mei, Yong-Liang Chen, Rui-Dan Zhong, Qing-Xin Dong, Peng-Tao Yang, Shu-Gang Tan, Bo-Sen Wang, Huiqian Luo, Jin-Guang Cheng, Xue Ming, Cao Wang, Guang-Han Cao

Abstract: We report the synthesis, structure and physical properties of a new quaternary nitride LaCr$_2$Ge$_2$N. The compound crystallizes in the CeCr$_2$Si$_2$C-type structure (P4/mmm), featuring distinctive Cr$_2$N square sheets within Cr$_2$Ge$_2$N block layers. Physical characterizations reveal enhanced electron correlations evidenced by a Sommerfeld coefficient substantially larger than band calculati… ▽ More We report the synthesis, structure and physical properties of a new quaternary nitride LaCr$_2$Ge$_2$N. The compound crystallizes in the CeCr$_2$Si$_2$C-type structure (P4/mmm), featuring distinctive Cr$_2$N square sheets within Cr$_2$Ge$_2$N block layers. Physical characterizations reveal enhanced electron correlations evidenced by a Sommerfeld coefficient substantially larger than band calculations and pressure-induced deviation from Fermi-liquid behavior. Magnetic measurements show short-range antiferromagnetic correlations developing around 460 K, followed by long-range magnetic ordering at 14 K. Additionally, subtle anomalies at 378 K suggest possible electronic ordering. First-principles calculations reveal nearly-flat Cr-3d bands near the Fermi level and predict a striped antiferromagnetic ground state. This work demonstrates how electron count variation in the CeCr$_2$Si$_2$C-type structure family leads to magnetic ordering in LaCr$_2$Ge$_2$N, contrasting with the paramagnetic behavior of LnCr$_2$Si$_2$C compounds. △ Less

Submitted 23 December, 2025; originally announced December 2025.

Comments: 8 pages, 5 figures, 3 tables. Accepted for publication in Physical Review B

Journal ref: Phys. Rev. B 112, 235164 (2025)

Kinetics of Bose-Einstein condensation of magnons in Yttrium Iron Garnet films

Authors: Hulin Yang, Gang Li, Haichen Jia, Artem Abanov, Valery Pokrovsky

Abstract: In this article, we explain the reason of the apparent contradiction between recent experiments [1] and [2] and earlier theoretical predictions [3] of strongly asymmetric condensate resulting in attractive interaction between the condensate magnons. We show that the relaxation time for equilibrium between two condensates at two minima of energy exceeds the time of experiment. Therefore, it should… ▽ More In this article, we explain the reason of the apparent contradiction between recent experiments [1] and [2] and earlier theoretical predictions [3] of strongly asymmetric condensate resulting in attractive interaction between the condensate magnons. We show that the relaxation time for equilibrium between two condensates at two minima of energy exceeds the time of experiment. Therefore, it should be described by Boltzmann kinetic equation. We develop the proper kinetic theory and find the relation between the critical pumping power and the effective temperature of over-condensate magnons. △ Less

Submitted 19 December, 2025; originally announced December 2025.

Theoretical study on the electronic properties and multiorbital models of La$_3$Ni$_2$O$_7$ thin films on SrLaAlO$_4$ (001)

Authors: Guanlin Li, Cui-Qun Chen, Haoliang Shi, Zhengtao Liu, Hao Ma, Fubo Tian, Dao-Xin Yao, Defang Duan

Abstract: The realization of ambient-pressure superconductivity in La$_3$Ni$_2$O$_7$ thin films raises a fundamental question: is the metallic ground state driven by lattice strain or interfacial charge reconstruction? Using fully self-consistent DFT+$U$ calculations on La$_3$Ni$_2$O$_7$/SrLaAlO$_4$ heterostructures, we identify that intrinsic hole doping via interfacial Sr interdiffusion is the decisive fa… ▽ More The realization of ambient-pressure superconductivity in La$_3$Ni$_2$O$_7$ thin films raises a fundamental question: is the metallic ground state driven by lattice strain or interfacial charge reconstruction? Using fully self-consistent DFT+$U$ calculations on La$_3$Ni$_2$O$_7$/SrLaAlO$_4$ heterostructures, we identify that intrinsic hole doping via interfacial Sr interdiffusion is the decisive factor in stabilizing the metallic state. Our 1-unit-cell model accurately reproduces the ARPES-observed Fermi surface, particularly the critical Ni-$d_{z^2}$ derived $γ$ hole pocket, which originates exclusively from the interface-proximal bilayer. Furthermore, comparative tight-binding analysis suggests that the reduced superconducting transition temperature ($T_c$) in thin films stems from the synergistic suppression of the electronic density of states (DOS) and vertical superexchange coupling ($J \perp Z$). These findings highlight that interface engineering plays a critical role beyond simple strain imposition in modulating nickelate orbital physics. △ Less

Submitted 19 December, 2025; originally announced December 2025.

Comments: 18 pages, 6 figures

Evaluating Large Language Models in Scientific Discovery

Authors: Zhangde Song, Jieyu Lu, Yuanqi Du, Botao Yu, Thomas M. Pruyn, Yue Huang, Kehan Guo, Xiuzhe Luo, Yuanhao Qu, Yi Qu, Yinkai Wang, Haorui Wang, Jeff Guo, Jingru Gan, Parshin Shojaee, Di Luo, Andres M Bran, Gen Li, Qiyuan Zhao, Shao-Xiong Lennon Luo, Yuxuan Zhang, Xiang Zou, Wanru Zhao, Yifan F. Zhang, Wucheng Zhang , et al. (31 additional authors not shown)

Abstract: Large language models (LLMs) are increasingly applied to scientific research, yet prevailing science benchmarks probe decontextualized knowledge and overlook the iterative reasoning, hypothesis generation, and observation interpretation that drive scientific discovery. We introduce a scenario-grounded benchmark that evaluates LLMs across biology, chemistry, materials, and physics, where domain exp… ▽ More Large language models (LLMs) are increasingly applied to scientific research, yet prevailing science benchmarks probe decontextualized knowledge and overlook the iterative reasoning, hypothesis generation, and observation interpretation that drive scientific discovery. We introduce a scenario-grounded benchmark that evaluates LLMs across biology, chemistry, materials, and physics, where domain experts define research projects of genuine interest and decompose them into modular research scenarios from which vetted questions are sampled. The framework assesses models at two levels: (i) question-level accuracy on scenario-tied items and (ii) project-level performance, where models must propose testable hypotheses, design simulations or experiments, and interpret results. Applying this two-phase scientific discovery evaluation (SDE) framework to state-of-the-art LLMs reveals a consistent performance gap relative to general science benchmarks, diminishing return of scaling up model sizes and reasoning, and systematic weaknesses shared across top-tier models from different providers. Large performance variation in research scenarios leads to changing choices of the best performing model on scientific discovery projects evaluated, suggesting all current LLMs are distant to general scientific "superintelligence". Nevertheless, LLMs already demonstrate promise in a great variety of scientific discovery projects, including cases where constituent scenario scores are low, highlighting the role of guided exploration and serendipity in discovery. This SDE framework offers a reproducible benchmark for discovery-relevant evaluation of LLMs and charts practical paths to advance their development toward scientific discovery. △ Less

Submitted 7 May, 2026; v1 submitted 17 December, 2025; originally announced December 2025.

Probabilistic Predictions of Process-Induced Deformation in Carbon/Epoxy Composites Using a Deep Operator Network

Authors: Elham Kiyani, Amit Makarand Deshpande, Madhura Limaye, Zhiwei Gao, Zongren Zou, Sai Aditya Pradeep, Srikanth Pilla, Gang Li, Zhen Li, George Em Karniadakis

Abstract: Fiber reinforcement and polymer matrix respond differently to manufacturing conditions due to mismatch in coefficient of thermal expansion and matrix shrinkage during curing of thermosets. These heterogeneities generate residual stresses over multiple length scales, whose partial release leads to process-induced deformation (PID), requiring accurate prediction and mitigation via optimized non-isot… ▽ More Fiber reinforcement and polymer matrix respond differently to manufacturing conditions due to mismatch in coefficient of thermal expansion and matrix shrinkage during curing of thermosets. These heterogeneities generate residual stresses over multiple length scales, whose partial release leads to process-induced deformation (PID), requiring accurate prediction and mitigation via optimized non-isothermal cure cycles. This study considers a unidirectional AS4 carbon fiber/amine bi-functional epoxy prepreg and models PID using a two-mechanism framework that accounts for thermal expansion/shrinkage and cure shrinkage. The model is validated against manufacturing trials to identify initial and boundary conditions, then used to generate PID responses for a diverse set of non-isothermal cure cycles (time-temperature profiles). Building on this physics-based foundation, we develop a data-driven surrogate based on Deep Operator Networks (DeepONets). A DeepONet is trained on a dataset combining high-fidelity simulations with targeted experimental measurements of PID. We extend this to a Feature-wise Linear Modulation (FiLM) DeepONet, where branch-network features are modulated by external parameters, including the initial degree of cure, enabling prediction of time histories of degree of cure, viscosity, and deformation. Because experimental data are available only at limited time instances (for example, final deformation), we use transfer learning: simulation-trained trunk and branch networks are fixed and only the final layer is updated using measured final deformation. Finally, we augment the framework with Ensemble Kalman Inversion (EKI) to quantify uncertainty under experimental conditions and to support optimization of cure schedules for reduced PID in composites. △ Less

Submitted 1 May, 2026; v1 submitted 14 December, 2025; originally announced December 2025.

Comments: 21 pages, 13 figures

F2: Offline Reinforcement Learning for Hamiltonian Simulation via Free-Fermionic Subroutine Compilation

Authors: Ethan Decker, Christopher Watson, Junyu Zhou, Yuhao Liu, Chenxu Liu, Ang Li, Gushu Li, Samuel Stein

Abstract: Compiling shallow and accurate quantum circuits for Hamiltonian simulation remains challenging due to hardware constraints and the combinatorial complexity of minimizing gate count and circuit depth. Existing optimization method pipelines rely on hand-engineered classical heuristics, which cannot learn input-dependent structure and therefore miss substantial opportunities for circuit reduction.… ▽ More Compiling shallow and accurate quantum circuits for Hamiltonian simulation remains challenging due to hardware constraints and the combinatorial complexity of minimizing gate count and circuit depth. Existing optimization method pipelines rely on hand-engineered classical heuristics, which cannot learn input-dependent structure and therefore miss substantial opportunities for circuit reduction. We introduce F2, an offline reinforcement learning framework that exploits free-fermionic structure to efficiently compile Trotter-based Hamiltonian simulation circuits. F2 provides (i) a reinforcement-learning environment over classically simulatable free-fermionic subroutines, (ii) architectural and objective-level inductive biases that stabilize long-horizon value learning, and (iii) a reversible synthetic-trajectory generation mechanism that consistently yields abundant, guaranteed-successful offline data. Across benchmarks spanning lattice models, protein fragments, and crystalline materials (12-222 qubits), F2 reduces gate count by 47% and depth by 38% on average relative to strong baselines (Qiskit, Cirq/OpenFermion) while maintaining average errors of 10^(-7). These results show that aligning deep reinforcement learning with the algebraic structure of quantum dynamics enables substantial improvements in circuit synthesis, suggesting a promising direction for scalable, learning-based quantum compilation △ Less

Submitted 10 December, 2025; v1 submitted 8 December, 2025; originally announced December 2025.

Disorder Suppression of Charge Density Waves in the Honeycomb Holstein Model

Authors: Guangchao Li, Lifei Zhang, Tianxing Ma, Qionglin Dai, Lufeng Zhang

Abstract: The formation of charge-density-wave order in Dirac fermion systems via electron-phonon coupling represents a significant topic in condensed matter physics. In this work, we investigate this phenomenon within the Holstein model on the honeycomb lattice, with a specific focus on the effect of disorder. While the interplay between electron-electron interactions and disorder has long been a central t… ▽ More The formation of charge-density-wave order in Dirac fermion systems via electron-phonon coupling represents a significant topic in condensed matter physics. In this work, we investigate this phenomenon within the Holstein model on the honeycomb lattice, with a specific focus on the effect of disorder. While the interplay between electron-electron interactions and disorder has long been a central theme in the field, recent attention has increasingly turned to the combined influence of disorder and electron-phonon coupling. Using determinant quantum Monte Carlo simulations, we concentrate on the phase transitions of charge-density-wave order on the honeycomb lattice. Disorder is introduced through the random hopping of electrons in the system, which can localize electrons via the Anderson effect. Our primary result is that disorder suppresses the charge-density-wave phase, and the interplay between disorder and electron-phonon interactions extends the phase area. We also determine the transition temperature \(β_c\) to the ordered phase as a function of the electron-phonon coupling. Additionally, we observed a suppression of electron kinetic energy and dc conductivity under disorder, highlighting the role of Anderson localization in the degradation of electronic transport. These findings offer significant theoretical insight into the stability and critical phenomena of correlated phases in disordered two-dimensional systems. △ Less

Submitted 16 July, 2026; v1 submitted 1 December, 2025; originally announced December 2025.

Comments: 10 pages, 12 figures, theoretical study on condensed matter physics (honeycomb lattice Holstein model); no generative AI tools used in research

Journal ref: Phys. Rev. B 113, 085144 (2026)

The bulk modulus of three-dimensional quantum droplets

Authors: Zibin Zhao, Guilong Li, Zhaopin Chen, Huan-Bo Luo, Bin Liu, Boris A. Malomed, Yongyao Li

Abstract: Quantum droplets (QDs), formed by ultradilute quantum fluids under the action of the Lee-Huang-Yang (LHY) effect, provide a unique platform for investigating a wide range of macroscopic quantum effects. Recent studies of QDs' breathing modes and collisional dynamics have revealed their compressibility and extensibility, which suggests that their elasticity parameters can be identified. In this wor… ▽ More Quantum droplets (QDs), formed by ultradilute quantum fluids under the action of the Lee-Huang-Yang (LHY) effect, provide a unique platform for investigating a wide range of macroscopic quantum effects. Recent studies of QDs' breathing modes and collisional dynamics have revealed their compressibility and extensibility, which suggests that their elasticity parameters can be identified. In this work we derive the elastic bulk modulus (BM) of QDs by means of theoretical analysis and numerical simulations and establish a relation between the BM and the eigenfrequency of the QD's intrinsic vibrations. The analysis reveals the dependence of the QD's elasticity on the particle number and the strength of interparticle interactions. We additionally provide a realistic estimate of the bulk modulus for the system, yielding a concrete physical value that may serve as a reference for future experimental measurements. Taken together, these results also point to possibilities for realizing elastic media governed by the LHY effect. △ Less

Submitted 21 April, 2026; v1 submitted 4 November, 2025; originally announced November 2025.

Comments: 9 pages, 5 figures, and 66 References

Journal ref: Physical Review A 113, 043315 (2026)

Applications of Machine Learning in Polymer Materials: Property Prediction, Material Design, and Systematic Processes

Authors: Hongtao Guo Shuai Li Shu Li

Abstract: This paper systematically reviews the research progress and application prospects of machine learning technologies in the field of polymer materials. Currently, machine learning methods are developing rapidly in polymer material research; although they have significantly accelerated material prediction and design, their complexity has also caused difficulties in understanding and application for r… ▽ More This paper systematically reviews the research progress and application prospects of machine learning technologies in the field of polymer materials. Currently, machine learning methods are developing rapidly in polymer material research; although they have significantly accelerated material prediction and design, their complexity has also caused difficulties in understanding and application for researchers in traditional fields. In response to the above issues, this paper first analyzes the inherent challenges in the research and development of polymer materials, including structural complexity and the limitations of traditional trial-and-error methods. To address these problems, it focuses on introducing key basic technologies such as molecular descriptors and feature representation, data standardization and cleaning, and records a number of high-quality polymer databases. Subsequently, it elaborates on the key role of machine learning in polymer property prediction and material design, covering the specific applications of algorithms such as traditional machine learning, deep learning, and transfer learning; further, it deeply expounds on data-driven design strategies, such as reverse design, high-throughput virtual screening, and multi-objective optimization. The paper also systematically introduces the complete process of constructing high-reliability machine learning models and summarizes effective experimental verification, model evaluation, and optimization methods. Finally, it summarizes the current technical challenges in research, such as data quality and model generalization ability, and looks forward to future development trends including multi-scale modeling, physics-informed machine learning, standardized data sharing, and interpretable machine learning. △ Less

Submitted 29 October, 2025; originally announced October 2025.

Comments: 55 pages, 6 tables, 9 figures, a systematic review on the research progress and application prospects of machine learning in polymer materials

Broad nonlocal spectrum in the Pb-InSb hybrid three terminals for potential realization of Kitaev chains

Authors: Guoan Li, Xiaofan Shi, Ruixuan Zhang, Yuxiao Song, Marco Rossi, Ghada Badawy, Zhiyuan Zhang, Anqi Wang, Xingchen Guo, Xiao Deng, Xiao Chen, Liangqian Xu, Bingbing Tong, Peiling Li, Xiaohui Song, Zhaozheng Lyu, Guangtong Liu, Fanming Qu, Michał P. Nowak, Paweł Wójcik, Ziwei Dou, Erik P. A. M. Bakkers, Li Lu, Jie Shen

Abstract: Hybrid superconductor-semiconductor(SC-SM) nanowires remain one of the foremost platforms for engineering topological superconductivity and Majorana zero modes(MZMs) towards fault-tolerant topological qubits, especially with the rapid development of artificial Kitaev chains. In contrast to the widely used aluminum(Al)-based hybrids, lead(Pb) offers a bulk superconducting gap of ~1.4meV and a criti… ▽ More Hybrid superconductor-semiconductor(SC-SM) nanowires remain one of the foremost platforms for engineering topological superconductivity and Majorana zero modes(MZMs) towards fault-tolerant topological qubits, especially with the rapid development of artificial Kitaev chains. In contrast to the widely used aluminum(Al)-based hybrids, lead(Pb) offers a bulk superconducting gap of ~1.4meV and a critical temperature of ~7.2K, giving rise to a proximity-induced gap that is roughly five times larger than that obtained with Al. Here we present the first three-terminal Pb-hybrid devices and perform nonlocal differential-conductance spectroscopy on this platform. The nonlocal measurement simultaneously resolves a dual-gap feature of the parent Pb gap and the large, hard, gate-tunable induced superconducting gap, distinguished by a switch between electron- and hole-like dissipation processes. Within the induced gap we observe several types of Andreev bound states(ABSs) that undergo singlet-doublet transitions. Moreover, by tuning gate voltages we achieve gate-controlled resonating sign reversals of the nonlocal conductance, identifying three distinct regimes that correspond to different configurations of quantum-dot(QD) resonances(single-resonance, double-resonance, and series-resonance). Finally, the coupling between ABSs and QDs also present and can be modulated from the weak- to strong-coupling limit, indicating the feasibility of realizing the artificial Kitaev chains. Crucially, the robust nonlocal signatures persist up to temperatures(~1K) far above the operating temperature of Al-based devices thanks to the unusually large induced gap, thereby widening the accessible parameter space greatly and underscoring the suitability of Pb-based hybrids for implementing warm temperature artificial Kitaev chains and the topological quantum devices protected by a substantially larger topological gap. △ Less

Submitted 11 October, 2025; originally announced October 2025.

Magnetic-Field Control of Tomonaga-Luttinger Liquids in Ta2Pd3Te5 Edge States

Authors: Xingchen Guo Anqi Wang, Xiutong Deng, Yupeng Li, Guoan Li, Zhiyuan Zhang, Xiaofan Shi, Xiao Deng, Ziwei Dou, Guangtong Liu, Fanming Qu, Zhijun Wang, Tian Qian, Youguo Shi, Li Lu, Jie Shen

Abstract: Ta2Pd3Te5 is a quasi-one-dimensional transition-metal telluride whose heavy atoms endow the material with strong spin-orbit coupling, while the Fermi level inside the bulk gap makes the low-energy electronic structure highly tunable.Theory and early experiments have already identified a wealth of emergent phases in this platform: an excitonic insulator driven by electron-hole binding, a second-ord… ▽ More Ta2Pd3Te5 is a quasi-one-dimensional transition-metal telluride whose heavy atoms endow the material with strong spin-orbit coupling, while the Fermi level inside the bulk gap makes the low-energy electronic structure highly tunable.Theory and early experiments have already identified a wealth of emergent phases in this platform: an excitonic insulator driven by electron-hole binding, a second-order topological insulator protected by crystalline symmetry, a potential topological-protected quantum-spin-Hall edge, and proximity-induced edge supercurrents when coupled to a conventional s-wave superconductor. These properties make it a promising platform for hosting Majorana zero modes and quantum computation, provided that time-reversal symmetry can be broken by a Zeeman gap. In this work, we demonstrate that the one-dimensional edge channels of exfoliated Ta2Pd3Te5 host a robust and tunable Tomonaga-Luttinger liquid by electrostatic gating because it shifts the chemical potential across the bulk gap without changing the gap size. More importantly, the application of a magnetic field introduces a Zeeman gap that systematically increases the TLL power-law exponent alpha. Furthermore, rotating the field reveals a pronounced twofold anisotropy--alpha is maximal for a field parallel to the edge and minimal for a perpendicular orientation--originating from an orientation-dependent edge g-factor that is likely amplified by quantum-confinement-induced orbital-angular-moment quenching. The existence of gate-tunable edge supercurrents together with the field-controlled Zeeman gap provides a direct route to break time-reversal symmetry in a particle-hole-symmetric superconducting gap and thus to engineer a topological superconducting phase, paving the way towards Majorana-based quantum devices. △ Less

Submitted 9 October, 2025; originally announced October 2025.

Magnon squeezing near a quantum critical point in a cavity-magnon-qubit system

Authors: Gang Liu, Gen Li, Rong-Can Yang, Wei Xiong, Jie Li

Abstract: Preparing magnon nonclassical states is a central topic in the study of quantum magnonics. Here we propose to generate magnon squeezed states in a hybrid cavity-magnon-qubit system by engineering an effective Rabi-type magnon-qubit interaction. This is achieved by adiabatically eliminating the cavity mode and driving the qubit with two microwave fields, of which the driving frequencies and amplitu… ▽ More Preparing magnon nonclassical states is a central topic in the study of quantum magnonics. Here we propose to generate magnon squeezed states in a hybrid cavity-magnon-qubit system by engineering an effective Rabi-type magnon-qubit interaction. This is achieved by adiabatically eliminating the cavity mode and driving the qubit with two microwave fields, of which the driving frequencies and amplitudes are properly selected. By operating the system around the critical point associated with the ground-state superradiant phase transition in the normal phase, a magnon parametric amplification-like interaction is induced, leading to a dynamical magnon squeezing. We further analyze the effects of the dissipation, dephasing, and thermal noise on the magnon squeezing. Our results indicate that a moderate degree of squeezing can be produced using currently available parameters in the experiments. △ Less

Submitted 22 February, 2026; v1 submitted 29 September, 2025; originally announced September 2025.

Comments: accepted to PRA

Journal ref: Phys. Rev. A 113, 033707 (2026)

Sub-spin-flop switching of a fully compensated antiferromagnet by magnetic field

Authors: Honglin Zhou, Muyu Wang, Yinina Ma, Xiaoyan Ma, Gang Li, Zihao Tao, Xiquan Zheng, Liqin Yan, Yingying Peng, Ding-Fu Shao, Bo Liu, Shiliang Li

Abstract: The control of antiferromagnets by magnetic fields represents a fundamental challenge in condensed matter physics, owing to their fully compensated magnetic order and vanishing net magnetization. Conventional methods rely on either uncompensated moments or high-field spin-flop transitions. Here, we demonstrate low-field switching in the fully compensated antiferromagnet CeNiAsO -- a material recen… ▽ More The control of antiferromagnets by magnetic fields represents a fundamental challenge in condensed matter physics, owing to their fully compensated magnetic order and vanishing net magnetization. Conventional methods rely on either uncompensated moments or high-field spin-flop transitions. Here, we demonstrate low-field switching in the fully compensated antiferromagnet CeNiAsO -- a material recently proposed as a candidate for $p$-wave magnetism. Using an in-plane magnetic field well below the spin-flop threshold, we selectively stabilize one of two degenerate antiferromagnetic domains with mutually orthogonal sublattice orientations. This field-induced domain selection allows reversible and nonvolatile switching of a giant in-plane resistivity anisotropy up to $\sim35\,\%$ -- a magnitude that far exceeds conventional anisotropy signals driven by spin-orbit coupling. The switching behavior persists across both the low-temperature noncollinear Néel phase and the higher-temperature collinear spin-density-wave phase, highlighting the universality of the domain-selection mechanism. Our work establishes a practical approach for manipulating compensated antiferromagnets with modest magnetic fields and underscores their potential for high-performance spintronic devices based on giant and switchable resistivity anisotropy. △ Less

Submitted 16 April, 2026; v1 submitted 8 September, 2025; originally announced September 2025.

Comments: 7 pages, 5 figures

NeuroQD: A Learning-Based Simulation Framework For Quantum Dot Devices

Authors: Shize Che, Junyu Zhou, Seong Woo Oh, Jonathan Hess, Noah Johnson, Mridul Pushp, Robert Spivey, Anthony Sigillito, Gushu Li

Abstract: Electron spin qubits in quantum dot devices are promising for scalable quantum computing. However, architectural support is currently hindered by the lack of realistic and performant simulation methods for real devices. Physics-based tools are accurate yet too slow for simulating device behavior in real-time, while qualitative models miss layout and wafer heterostructure. We propose a new simulati… ▽ More Electron spin qubits in quantum dot devices are promising for scalable quantum computing. However, architectural support is currently hindered by the lack of realistic and performant simulation methods for real devices. Physics-based tools are accurate yet too slow for simulating device behavior in real-time, while qualitative models miss layout and wafer heterostructure. We propose a new simulation approach capable of simulating real devices from the cold-start with real-time performance. Leveraging a key phenomenon observed in physics-based simulation, we train a compact convolutional neural network (CNN) to infer the qubit-layer electrostatic potential from gate voltages. Our GPU-accelerated inference delivers >1000x speedup with >96% agreement to the physics-based simulation. Integrated into the experiment control stack, the simulator returns results with millisecond scale latency, reproduces key tuning features, and yields device behaviors and metrics consistent with measurements on devices operated at 9 mK. △ Less

Submitted 2 September, 2025; originally announced September 2025.

Three-Dimensional Continuous Multi-Walled Carbon Nanotubes Network-Toughened Diamond Composite

Authors: Jiawei Zhang, Keliang Qiu, Tengfei Xu, Xi Shen, Junkai Li, Fengjiao Li, Richeng Yu, Huiyang Gou, Duanwei He, Liping Wang, Zhongzhou Wang, Guodong Li, Yusheng Zhao, Ke Chen, Fang Hong, Ruifeng Zhang, Xiaohui Yu

Abstract: Enhancing the fracture toughness of diamond while preserving its hardness is a significant challenge. Traditional toughening strategies have primarily focused on modulating the internal microstructural units of diamonds, including adjustments to stacking sequences, faults, nanotwinning, and the incorporation of amorphous phases, collectively referred to as intrinsic toughening. Here, we introduce… ▽ More Enhancing the fracture toughness of diamond while preserving its hardness is a significant challenge. Traditional toughening strategies have primarily focused on modulating the internal microstructural units of diamonds, including adjustments to stacking sequences, faults, nanotwinning, and the incorporation of amorphous phases, collectively referred to as intrinsic toughening. Here, we introduce an extrinsic toughening strategy to develop an unparalleled tough diamond composite with complex and abundant sp2-sp3 bonding interfaces, by incorporating highly dispersed multi-walled carbon nanotubes (MWCNTs) into the gaps of diamond grains to create a three-dimensional (3D) continuous MWCTNs network-toughen heterogeneous structure. The resultant composite exhibits a hardness of approximately 91.6 GPa and a fracture toughness of roughly 36.4 MPa.m1/2, which is six times higher than that of synthetic diamond and even surpasses that of tungsten alloys, surpassing the benefits achievable through intrinsic toughening alone. The remarkable toughening behavior can be attributed to the formation of numerous mixed sp2-sp3 bonding interactions at the 3D continuous network MWCNTs/diamond interfaces, which facilitate efficient energy dissipation. Our 3D continuous network heterogeneous structure design provides an effective approach for enhancing the fracture toughness of superhard materials, offering a new paradigm for the advanced composite ceramics. △ Less

Submitted 25 August, 2025; originally announced August 2025.

Emergent dynamical Kondo coherence and competing magnetic order in a correlated kagome flat-band metal CsCr6Sb6

Authors: Xiangqi Liu, Xuefeng Zhang, Jiachen Jiao, Renjie Zhang, Kaiwen Chen, Ying Wang, Yunguan Ye, Zhenhai Yu, Chengyu Jiang, Xia Wang, Lei Shu, Baiqing Lv, Gang Li, Yanfeng Guo

Abstract: Correlated kagome metals host unique electronic states that enable exotic quantum phenomena. In the recently emerged CsCr6Sb6, these manifest through Kondo behavior from localized Cr-3d electrons and unprecedented band flattening near the Fermi level. Yet the intricate interplay among Kondo screening, magnetic frustration, and electronic correlations remains poorly understood-a fundamental gap we… ▽ More Correlated kagome metals host unique electronic states that enable exotic quantum phenomena. In the recently emerged CsCr6Sb6, these manifest through Kondo behavior from localized Cr-3d electrons and unprecedented band flattening near the Fermi level. Yet the intricate interplay among Kondo screening, magnetic frustration, and electronic correlations remains poorly understood-a fundamental gap we address through multifaceted experimental and theoretical approaches. Our angle-resolved photoemission spectroscopy measurements reveal electronic correlation-renormalized flat bands and muon spin relaxation study detect short-range magnetic order at TN ~ 80 K. Complementing these findings, density-functional theory and dynamical mean-field theory calculations identify a coherent-incoherent crossover at TN, with a remarkable restoration of coherence accompanying local moment suppression-an anomalous hallmark of Kondo behavior. Intriguingly, despite strong interlayer antiferromagnetic coupling, the system evades long-range magnetic order due to competing magnetic configurations separated by sub-meV energy differences. These insights establish CsCr6Sb6 as a prototypical platform for investigating dynamical Kondo screening in correlated flat-band systems, opening new avenues to study flat band physics and frustrated magnetism in correlated kagome lattices. △ Less

Submitted 11 August, 2025; originally announced August 2025.

Comments: Mian Text 17 pages, 4 figures; SI 9 pages, 7 figures, 1 table

Journal ref: Physical Review Letters 2026, 136: 256601