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Jian Zhou

Publications and source records attributed to Jian Zhou.

At least 19 recordsLinked to original sources

Reflex-Informed Neuromuscular Reinforcement Learning for Muscle-Driven Locomotion

Muscle-driven locomotion provides a physically grounded approach to generating realistic human movement. However, achieving both physiological plausibility and adaptability to changes in musculoskeletal capacity and external disturbances remains a fundamental challenge. To address this limitation, we propose a Reflex-Informed Neuromuscular Reinforcement Learning framework for muscle-driven locomotion. Within this framework, a fixed phase-dependent reflex controller serves as the underlying neuromuscular control mechanism, while the reinforcement learning policy produces four biomechanically meaningful residual parameters to modulate key reflex gains and thresholds associated with hip swing, knee support, and ankle propulsion according to the current state. Experimental results demonstrate that the proposed framework generates physiologically plausible locomotion with improved kinematic accuracy and dynamic consistency, as well as better bilateral symmetry and stride-to-stride consistency under nominal walking conditions. The learned policy remains robust under muscle weakness and external perturbations without retraining.

cs.RO

Same Values, Different Languages? From Multilingual Probing to Steering LLMs Toward Chinese Social Values

As Large Language Models (LLMs) are increasingly integrated into human society, aligning them with pluralistic social values has become a critical priority. However, whether LLMs exhibit consistent value preferences across languages remains underexplored, particularly for culturally grounded values, which are more abstract and difficult to evaluate and align than safety-centric principles. We investigate this issue through Chinese Social Values (CSV), a value system rooted in Chinese culture and comprising $12$ dimensions across national, societal, and personal levels. We construct C-Voices, the first comprehensive multilingual contrastive probe dataset for CSV, with 86,400 dilemma-based instances in six languages, each pairing a CSV-aligned action with a value-conflicting alternative. Building on the contrastive probes of C-Voices, we then propose a fine-tuning-free value vector steering method that derives value directions from hidden-state discrepancies and selectively intervenes on value-sensitive layers during inference. Experiments on six languages show that CSV-oriented preferences are model-dependent and language-sensitive, with the same dilemma eliciting divergent responses across languages. Our method achieves effective CSV steering, supports cross-lingual transfer of value vectors, and generalizes to existing FLAMES and ValuePrism.

cs.CL

CRISP: Corneal Confocal Microscopy Real-Time Image Stitching Pipeline

Morphology of the sub-basal nerve plexus (SNP) reflects peripheral nerve health, and corneal confocal microscopy (CCM) provides an important means for in vivo, real-time, non-invasive observation of the SNP. However, mainstream CCM devices offer a limited field of view per frame, whereas the SNP is spatially non-uniform; discrete image sampling is therefore sensitive to sampling location and frame selection, which limits the reproducibility and clinical adoption of CCM as a quantitative assessment tool. Wide-field stitching can reconstruct larger SNP mosaics by integrating sequentially acquired CCM images, but existing methods largely rely on offline post-processing, additional hardware, or specific acquisition protocols, and lack open-source real-time solutions for conventional CCM video streams. This paper presents CRISP (Corneal confocal microscopy Real-time Image Stitching Pipeline), an open-source real-time SNP wide-field stitching framework for conventional CCM examination video streams. CRISP excludes defocused and discontinuous segments via focus-aware gating, propagates poses through local pairwise registration, and maintains non-redundant spatial coverage with a sparse anchor map; when local temporal continuity is interrupted, the system completes relocalization and subgraph merging through global appearance retrieval followed by geometric verification. The framework prioritizes low-latency coverage feedback during examination while outputting accepted frames, poses, and anchor information to initialize offline fine stitching. To our knowledge, CRISP is the first open-source real-time SNP wide-field stitching framework released for conventional CCM video streams. By lowering the barrier to adoption and reproduction of wide-field stitching, CRISP may help move SNP wide-field imaging from a research tool into routine clinical examination workflows.

cs.CV

Tracing Gluon Saturation through Hadronization at EIC

Gluon saturation provides a window into the nonlinear nature of the strong interaction in nuclear matter. One direct consequence of saturation is the $\boldsymbol{k}_T$ broadening in the final state.We investigate how hadronization reshapes conventional signatures of gluon saturation at EIC within a complete event-generator framework. To this end, we implement in eHIJING an initial-state-radiation algorithm based on nonlinear small-$x$ evolution and complete the events with beam remnants, final-state radiation, and hadronization. In our simulations, the signal of parton-level nuclear $\boldsymbol{k}_T$ broadening is strongly diluted in both the nucleon energy correlator and leading-dihadron azimuthal decorrelation after hadronization. Global hadronic recoil, by contrast, remains sensitive to the underlying $\boldsymbol{k}_T$ broadening. We further demonstrate that Bayesian unfolding of the global hadronic recoil provides access to the underlying hard-scattering $\boldsymbol{k}_T$ distribution. These results establish the global hadronic recoil as a promising saturation observable at the EIC.

hep-ph

Evading Sudakov Dilution in Gluon Tomography

Sudakov broadening and competing azimuthal harmonics from final-state soft radiation limit the precision of gluon tomography. We suppress both effects using fiducial hadronic recoil---the vector sum of all hadronic transverse momenta within a rapidity interval---while a tagged jet fixes the azimuthal axis. Momentum conservation ensures that emissions inside the interval contribute neither to recoil broadening nor to these harmonics, so widening the interval reduces their impact without a soft-radiation veto. As a benchmark, we study the $\cos 2\phi$ modulation probing $h_1^{\perp g}$ in DIS. For rapidity interval $\Delta\eta=3$, fiducial recoil enhances the $h_1^{\perp g}$ contribution by a factor of $4.6$ and suppresses the final-state soft gluon term by a factor of $4.0$ relative to the conventional dijet imbalance. Fiducial recoil thereby enables precision gluon-TMD tomography.

hep-ph

Recoil Geometry Unmasks Gluon Saturation in Forward $Z^0$ Production

Gluon saturation produces characteristic transverse-momentum broadening in nuclei, but QCD radiation largely washes out this signature. We show that fiducial recoil subtraction turns detector acceptance into a transverse-momentum projector that unmasks the broadening in forward $Z^0$ production. Subtracting the hadronic recoil measured in a chosen rapidity interval from the boson transverse momentum defines a residual momentum. At leading power, the radiative recoil in this interval cancels, while the residual momentum retains sensitivity to the small-$x$ nuclear field. Combining a CGC description of the small-$x$ target with soft-collinear effective theory (SCET) resummation for finite rapidity coverage, we find that a benchmark rapidity coverage $|\eta^{\rm lab}|<2.5$ lowers the effective hard scale from $M_Z\simeq 91.2$ GeV to about $7.5~\mathrm{GeV}$ of the Sudakov evolution. Increasing the saturation scale broadens the residual-momentum distribution and weakens recoil alignment, whereas wider coverage makes the proton--nucleus separation clearer in both observables. Detector geometry thus provides tunable control over perturbative recoil, enabling a probe of nonlinear small-$x$ QCD.

hep-ph

ALKEMIE Agent: an autonomous platform for computational materials design

Despite the powerful multi-scale modeling methods and high-throughput infrastructures established in the materials community, real material computation workflows remain fragmented and heavily manual, requiring researchers to constantly bridge software tools, data analysis, and intermediate decisions. This growing gap between methodological capability and practical execution highlights the need for a new kind of autonomous computational framework, one that can coordinate tools, knowledge, and workflows in a more unified and adaptive way. Here, we introduce ALKEMIE Agent, an agentic platform in which retrieval-augmented generation, a materials-computation knowledge base, registered skills, database-supported provenance, AI-assisted structure modeling, bounded task execution, tool-calling iteration, and error-diagnostic assistance are integrated within a traceable control loop. The capabilities of ALKEMIE Agent are demonstrated through applications including materials recommendation, structure modeling, phonon calculations, machine-learned interatomic potential training, LAMMPS simulations, Ab Initio Monte Carlo (AIMC) sampling, and active-learning-based materials screening. Finally, we outline the future directions and challenges for the development of agentic platforms for computational materials design.

cond-mat.mtrl-sci

Physics of the Electron-Ion Collider in China

The Electron-Ion Collider in China (EicC), a cutting-edge facility under development, aims to unveil the internal structure of nucleons and nuclei by leveraging collisions of high-intensity polarized electrons and ions (polarized protons, polarized deuterons, polarized $^{3}$He, and unpolarized heavy ions up to Uranium) at center-of-mass energies of 15-20 GeV and luminosity of (2-4)$\times 10^{33}$cm$^{-2}$s$^{-1}$. Its primary physics objectives include 3D tomography of nucleon spin and momentum structure, fundamental questions regarding the origin of nucleon mass, partonic structure of nuclei and parton interactions with the nuclear environment, and exploration of exotic hadronic states. In this paper, we review the physics potential of the EicC and highlight its unique capabilities for advancing precision nucleon structure studies by combining its specialized kinematic coverage and high luminosity. Since traditional topics like 3D nucleon structure have already been well-covered by several extensive reviews, we have deliberately dedicated significant space to recent progress in nucleon mass decomposition, nucleon energy-energy correlation, quantum information, and artificial intelligence applications in high-energy nuclear physics, which have been emerging rapidly and attracted a tremendous amount of attention in the community.

hep-ph

Nonresonant optomechanical control of structural phases

Optical tweezers demonstrate how light can exert forces to trap, repel, and manipulate microscopic particles without absorption. Recent theory has suggested that such forces can extend beyond particle manipulation to drive structural phase transitions in solids. Here we apply this optomechanical principle to tin selenide (SnSe), a material where proximity to several different structural phases gives rise to its high thermoelectric figure of merit and makes it a candidate for a switchable topological crystalline insulator. Whereas the force for standard optical tweezers arises from a gradient in the intensity of a light field, the optomechanical force is mediated by a gradient in the dielectric constant as a function of phonon coordinate. Unlike conventional methods that rely on resonant excitation and absorption through the imaginary part of the dielectric function, this approach operates dispersively through the real part and can be directly driven by Raman processes, enabling selective transitions with reduced energy cost and ultrafast response. Using time-domain Raman scattering, we show that above a critical mid-infrared field strength the $A_g$ Raman modes disappear abruptly without softening, signaling the formation of a new structural phase. This phase, distinct from those induced by heating or carrier excitation, exhibits large-amplitude and long-lived modulations in its optical response. Complementing this observation, we show also evidence for an equivalent DC-field-driven structural phase transformation to a higher symmetry phase, as observed by atom probe tomography. Our study demonstrates the concept of nonresonant optomechanical phase control and defines novel opportunities for synthesizing hidden structural phases with unique functional properties.

physics.optics

Pressure-Driven Evolution of Electronic and Magnetic Correlations in Bilayer Nickelate La3Ni2O7

The recent discovery of high-temperature superconductivity in pressurized bilayer La3Ni2O7 has sparked intense research interest, yet the microscopic mechanism governing its pressure-dependent superconducting transition temperature (Tc) remains elusive. In this work, we investigate the electronic and magnetic correlations of La3Ni2O7 under high pressure using a combination of density-functional theory (DFT), constrained random phase approximation (cRPA), and dynamical mean-field theory (DMFT). We find that while hydrostatic pressure enhances the interlayer hopping and the bare superexchange energy scale (4t2/U), it simultaneously drives the system toward a more itinerant regime by reducing the relative correlation strength (U/W). Crucially, our results reveal a distinct orbital-selective evolution: the Ni dx2-y2 states become increasingly itinerant, whereas the Ni dz2 orbitals retain a more localized character. This pressure-induced itinerancy significantly enhances the hybridization between the two, leading to a dramatic amplification of the Kondo-like screening of the local dz2 moments by the itinerant dx2-y2 electrons. Consequently, the effective magnetic exchange coupling (Jeff), which serves as the pairing glue, is suppressed in the high-pressure regime. Our findings suggest that the monotonic decrease of Tc at high pressures is driven by the dominance of Kondo screening over superexchange interactions, providing a coherent microscopic explanation for the dome-shaped superconducting phase diagram in La3Ni2O7.

cond-mat.str-el

Spin-chirality-driven nonrelativistic Edelstein effects in two-dimensional antiferromagnets

Charge current-induced magnetic moment accumulation-Edelstein effect has been extensively attracting attention for its promising applications in spintronics. While most prior works focus on the spin-orbit coupling (SOC) induced Edelstein responses that rely on the presence of heavy elements, the nonrelativistic Edelstein effect (in the absence of SOC) that could be applied in a broader material family has been largely unexplored. Here, we perform a combined group-theoretical and ab initio numerical simulation study to show that vector spin chirality could serve as an effective control parameter of nonrelativistic Edelstein responses in antiferromagnetic system. In addition to spin degree of freedom, we also explore the orbital angular momentum contributions to current-induced magnetic moments (dubbed orbital Edelstein effect), which obey distinct symmetry constraints from the spin counterpart. Microscopically, vector spin chirality k gives rise to electronic and Zeeman-like band-geometric quantities, such as the anomalous spin/orbital polarizability and the Berry connection polarizability, which govern the nonrelativistic Edelstein responses. Our work identifies vector spin chirality as a key magnetic order parameter to enable and tune nonrelativistic Edelstein effects, and uncovers a new route toward electrically controlling magnetization without relying on SOC effect.

cond-mat.mtrl-sci

Embodied Agents Take Control: Minimal-Interface Zero-Shot Agents Rival Industrial-Scale Policies in Vision-and-Language Navigation

Autonomous embodied agents must sustain a long decision-making loop that involves perceiving, acting, verifying, and self-correcting over many steps. Current systems sustain this loop through task-specific workflows or embodied policies. However, these fixed workflows and policies offer limited flexibility across environments and often lack effective recovery strategies when execution goes wrong. We find that a general-purpose agent can instead sustain the loop on its own. We term this organization agentic embodied control: the reasoning model directly steers every action, keeping reasoning and control aligned. Using zero-shot navigation as a controlled testbed, we equip three coding-agent harnesses with only a monocular RGB camera and discrete actions. At default effort, replicated opus-5 runs average $70.7\pm3.5$% success, while fable-5 reaches 78% at maximum effort. When a trained waypoint tool is offered alongside primitives, the hybrid fable-5 agent reaches $76.7\pm0.6$% at default effort, using half the environment steps and under a quarter of the wall time. Across the ablations, model choice dominates performance variation. Observed harness differences are modest, and forced waypoints help weaker models but can hinder stronger ones. Although longer horizons, latency, and context growth remain barriers to sustained autonomy, these results show that a general-purpose model can already achieve competitive embodied control without a navigation policy.

cs.RO

AI2Pot: A scalable and unified framework for machine-learning interatomic potential development and large-scale molecular dynamic simulations

Machine-learning interatomic potentials (MLIPs) bridge the accuracy of first-principles calculations and the efficiency required for large-scale molecular dynamics (MD) simulations. However, existing MLIP software remains fragmented across different model architectures, making it difficult to establish unified workflows that support flexible model development, efficient training, and scalable MD deployment. Here, we present AI2Pot, a scalable and unified MLIP framework that seamlessly integrates model training, evaluation, and large-scale MD simulations with PyTorch-compatible ecosystem. Instead of relying on generic automatic differentiation for expensive atomistic operators, AI2Pot re-engineers the core computations of Moment tensor potential (MTP) and Neuroevolution potential (NEP) for both training and inference using hand-crafted C++/CUDA code. These specialized operators constitute a unified computational backend shared by training and inference, improving training-inference consistency and reducing memory usage by avoiding large intermediate caches. As a result, AI2Pot enables fast inference for large-scale atomic systems containing millions of atoms on a single GPU, while retaining the flexibility of PyTorch for model construction, training, and evaluation. Trained models can be deployed in ASE and LAMMPS for MD simulations. Furthermore, AI2Pot provides a companion command-line toolkit (AI2Pot-cli) and Python APIs to facilitate practical MLIP workflows. By unifying high-performance atomistic computing with modern machine-learning ecosystems, AI2Pot offers an user-friendly end-to-end framework for the developing, training, and deploying MLIPs for large scale MD.

cond-mat.mtrl-sci

Hidden ordered compound-layer and its tailoring of the electronic/optical property in Ge2Sb2SexTe5-x alloys

Ge2Sb2SexTe5-x (GSST) alloys represent an emerging class of phase-change materials for integrated photonics. However, the microscopic origins underlying their superior performance compared to the parent compound Ge2Sb2Te5 remain elusive. By using atomic simulations, this work elucidates that the thermal stability and low optical loss of GSST are fundamentally governed by the formation of an in-layer compound-like structure with SeTe2 or Se2Te stoichiometry depending on the Se content, contrasting to the previously believed pure-element-layered model where Se and Te atoms occupy separate layers inside GSST. The newly identified compound-layered structures maintaining stability at temperature above 370 K, yield an enlarged bandgap, weakened antibonding character, and more importantly, a moderate refractive index as well as decreased extinction coefficient which align better with the experiment compared to the previously believed model. The present findings not only help bridge the long-standing theory-experiment gap regarding the optical properties of GSST by redefining its atomic structure, but also establish local chemical ordering as a critical materials design principle for high-performance photonics.

cond-mat.mtrl-sci

Automating the Design of Embodied Agent Architectures

Embodied agents are typically built as hand-designed compositions of perception, memory, planning, and action modules. This modularity exposes a large architectural design space, but current systems still rely on researcher intuition to choose where information is stored, how observations are processed, and how model calls are connected. Agent Architecture Search (AAS) automates such design for text-domain agents, but has not been systematically evaluated on perceptual embodied agents through simulator rollouts. We study this transfer. We introduce AgentCanvas, a typed-graph runtime that hosts embodied executors as editable node-and-wire programs with simulator-aware execution and episode-level logs, and KDLoop, a coding-agent search procedure that cycles through proposal, critique, experiment, and distillation, with triggered reflection after stalls. We evaluate three AAS variants across four embodied executors spanning vision-language navigation, embodied question answering, and language-conditioned manipulation. The resulting 3x4 matrix shows that architecture-level search can produce deployable and directional success-rate gains on embodied tasks, while one apparent high-scoring candidate is rejected as leak-bearing. At the same time, the experiments expose constraints that are muted in text-domain AAS: optimization signals can be masked by rollout noise, search can become trapped in local edit basins, and episode-level credit assignment only partially emerges even when detailed logs are available. These results characterize both the promise and the current limits of automated architecture search for embodied agents.

cs.RO

GRAFT: Adaptive DLM-Based Draft Tree Construction with Target-Distilled Edge Scoring

Tree-based speculative decoding raises the mean accepted tokens of standard speculative decoding by verifying multiple draft paths, and existing tree builders typically construct these paths through parent-conditioned expansion, where each child token is generated conditioned on its parent path. This construction is incompatible with diffusion language model (DLM) drafters such as DFlash, which produces all future-position distributions in a single forward pass. DDTree bridges this gap by treating high-probability tokens from each future-position distribution as candidate nodes and selecting edges between consecutive positions under a fixed node budget. However, its edge selection relies on token probability alone without modeling parent--child compatibility, so target-compatible tokens can be attached to wrong parents; moreover, its fixed budget ignores that the throughput-optimal tree size varies with the decoding state. We propose GRAFT, a draft-tree construction framework for DLM-based speculative decoding. GRAFT introduces Target-Distilled Edge Scoring (TDES), which distills parent--child preferences from target-model traces to select target-compatible edges, and State-Aware Budget Allocation (SABA), which sets the per-round tree budget by balancing expected draft gain against verification cost. Across multiple models and tasks, GRAFT achieves $2.13\times$--$6.36\times$ end-to-end speedup over autoregressive decoding while adding less than $0.5$\,ms of overhead per round, approximately $1.4\%$ of the target-model verification latency.

cs.CL

Bulk Photovoltaic Effect in Two-Dimensional Perovskite Oxides

Perovskite oxides ABO$_3$ host a rich interplay of charge, spin, lattice, and orbital degrees of freedom, giving rise to diverse quantum phenomena. In low-dimensional ABO$_3$, reduced symmetry can induce exotic quantum effects such as the two-dimensional electron gas and unconventional superconductivity. Using first-principles density functional theory, tight-binding modeling, and symmetry analysis, we show that ultrathin two-dimensional (2D) ABO$_3$ films -- exemplified by SrTiO$_3$ -- naturally break inversion symmetry, producing a spontaneous out-of-plane bulk photovoltaic (BPV) effect. This differs from previous studies on in-plane BPV current signals and is more applicable and experimentally detectable. Such an effect is highly tunable via thickness, strain, surface termination, crystallographic orientation, and Moir\'e twisting. These findings are broadly applicable to a wide range of 2D perovskite and other layer-resolved oxides.

cond-mat.mtrl-sci

On determinantal formulas for hermitian random matrices

In this paper, we give a direct proof of determinantal formulas for connected $k$-point functions for hermitian matrix models. We also give a new proof of KP integrability for them. From the viewpoint of KP hierarchy, we further give a new proof of the explicit formula for the corresponding affine coordinates. Furthermore, duality for some hermitian matrix models is proved.

math-ph