Showing 1–50 of 232 results for author: Jiang, X

Dissipation-tunable extended and localized steady states in a non-disordered lattice

Authors: Ming-Jie Tao, Yi-Ting Wang, Jing Li, Hongsheng Hou, Xiang-Ping Jiang, Lei Pan

Abstract: Dissipation is usually regarded as a source of decoherence that suppresses quantum interference and localization. Here we show that suitably engineered dissipation can instead be used to select localized or extended states in a strictly non-disordered one-dimensional lattice. The underlying clean lattice has spatially inhomogeneous hopping and supports both extended bulk states and localized bound… ▽ More Dissipation is usually regarded as a source of decoherence that suppresses quantum interference and localization. Here we show that suitably engineered dissipation can instead be used to select localized or extended states in a strictly non-disordered one-dimensional lattice. The underlying clean lattice has spatially inhomogeneous hopping and supports both extended bulk states and localized boundary states, including an algebraically localized bound state in the continuum. We introduce a nonlocal bond jump operator with a tunable relative phase and show that this phase selectively favors eigenstates with different spatial phase correlations. As a result, the long-time density matrix can be steered toward sectors dominated by localized or extended Hamiltonian eigenstates without changing any Hamiltonian parameter. The microscopic origin of the selection is quantified by the fraction of site pairs separated by a distance $l$ that are phase matched with the dissipative channel. We further characterize the dissipative quench through the quantum fidelity and show that the selected character of the steady state can persist after the dissipation is removed. Our results establish phase-selective bond dissipation as a route to controllable state preparation and transport manipulation in non-disordered lattices. △ Less

Submitted 20 August, 2026; originally announced August 2026.

Dephasing-induced distinct mobility edges in a dimerized off-diagonal quasicrystal

Authors: Ming-Jie Tao, Yi-Ting Wang, Jing Li, Hongsheng Hou, Xiang-Ping Jiang, Lei Pan

Abstract: Anderson localization and the mobility edge (ME) have been extensively studied in isolated aperiodic systems. Conventional theory suggests that dephasing and decoherence should disrupt localization and facilitate transport. In this work, we investigate localization behaviors in a dimerized off-diagonal Aubry-Andre-Harper (AAH) quasicrystal subject to on-site pure dephasing. In the strong-dephasing… ▽ More Anderson localization and the mobility edge (ME) have been extensively studied in isolated aperiodic systems. Conventional theory suggests that dephasing and decoherence should disrupt localization and facilitate transport. In this work, we investigate localization behaviors in a dimerized off-diagonal Aubry-Andre-Harper (AAH) quasicrystal subject to on-site pure dephasing. In the strong-dephasing limit, we apply adiabatic elimination within the Lindblad master equation framework to derive an effective classical Markov transition matrix that governs the dissipative relaxation dynamics. Counterintuitively, we demonstrate that pure dephasing can induce distinct MEs, including both conventional MEs separating extended and localized states and anomalous MEs separating multifractal critical states from localized states, even when all eigenstates of the original closed coherent system are delocalized or multifractal. Using fractal dimension finite-size scaling, wave-packet spreading dynamics, and energy spectrum statistics, we numerically verify the coexistence of fully extended, multifractal critical, and localized regions within the relaxation spectrum of the dissipative system, and construct the global dissipative phase diagram. These findings reveal that dephasing can see as a powerful mechanism for controlling localization transitions, thus enhancing our understanding of dissipative quasicrystal systems. △ Less

Submitted 18 August, 2026; originally announced August 2026.

Exact mobility rings in non-Hermitian quasiperiodically decorated Lieb lattices

Authors: Ming-Jie Tao, Yi-Ting Wang, Jing Li, Hongsheng Hou, Xiang-Ping Jiang, Lei Pan

Abstract: The mobility ring (MR), a critical boundary in the complex energy plane separating extended and localized states, is fundamental to understanding the Anderson transition in non-Hermitian (NH) disordered systems. While MRs have been extensively studied in one-dimensional (1D) NH quasiperiodic models, rigorous analytical frameworks beyond 1D remain critically scarce. Here, we investigate a class of… ▽ More The mobility ring (MR), a critical boundary in the complex energy plane separating extended and localized states, is fundamental to understanding the Anderson transition in non-Hermitian (NH) disordered systems. While MRs have been extensively studied in one-dimensional (1D) NH quasiperiodic models, rigorous analytical frameworks beyond 1D remain critically scarce. Here, we investigate a class of two-dimensional (2D) quasiperiodically decorated Lieb lattices (QDLLs) featuring complex incommensurate potentials selectively applied to the lattice vertices. By exactly mapping these 2D structures onto NH generalized Aubry-Andr{é}-Harper (AAH) models and leveraging extended-localized transition point, we analytically derive the Lyapunov exponents and obtain exact expressions for the MRs. These exact theoretical boundaries are strongly corroborated by numerical computations of wavefunction fractal dimensions and real-space probability distributions. Furthermore, we reveal distinct evolutionary behaviors of the MRs driven by the quasiperiodic potential strength: systems characterized by $κ=2$ possess a single MR, whereas systems with $κ=3$ undergo a dynamic sequential evolution from a single integrated ring into two independent rings. We hope that our exact results of MRs in 2D will benefit the study of Anderson localizations and MRs in high-dimensional NH systems. △ Less

Submitted 17 August, 2026; originally announced August 2026.

Strong Quantum Mpemba Effect from Exact Slow-Mode Selection in Constrained Rydberg Chains

Authors: Mingdi Xu, Kaixiang Lu, Zijun Wei, Xiang-Ping Jiang, Haiping Hu, Lei Pan

Abstract: CStrong quantum Mpemba acceleration requires suppressing the slowest visible Liouvillian relaxation channel, but a robust many-body mechanism for enforcing such suppression remains challenging. We identify such a mechanism in locally dephased constrained Rydberg chains through exact slow-mode selection. For constrained single-spin-flip Hamiltonians, local dephasing turns the Hamiltonian itself int… ▽ More CStrong quantum Mpemba acceleration requires suppressing the slowest visible Liouvillian relaxation channel, but a robust many-body mechanism for enforcing such suppression remains challenging. We identify such a mechanism in locally dephased constrained Rydberg chains through exact slow-mode selection. For constrained single-spin-flip Hamiltonians, local dephasing turns the Hamiltonian itself into an exact left Liouvillian eigenmode, $\mathcal L^\dagger(H)=-γH$. A finite-temperature reference state generically overlaps with this $H$-like slow mode, whereas translationally invariant states with $\mathrm{Tr}(Hρ_0)=0$ remove it and are confined to the $Q=0$ operator sector. When the next visible $Q=0$ mode decays faster, these selected states exhibit a strong quantum Mpemba effect. We demonstrate this mechanism in the PXP chain for a zero-energy scar eigenstate, the all-zero product state, and a translation-invariant $Z_2$ cat state, and show that it persists in the $(2,3)$ model and the longer-range blockade family. Our results identify Liouvillian mode visibility, rather than special scar wave functions, as the organizing principle for anomalously fast relaxation in constrained open quantum systems. △ Less

Submitted 4 August, 2026; v1 submitted 20 July, 2026; originally announced July 2026.

Comments: 8+13 pages, 4 figures, comments are welcome

In-Situ Polarimetry in Collimated Magneto-Infrared Spectroscopy System

Authors: Zeping Shi, Wenbin Wu, Zhiwei Zhang, Yuhan Du, Chenyao Xu, Congming Hao, Xiangyu Jiang, Xin Chen, Guangyi Wang, Mingsen Zhou, Chunhui Pan, Wei Lu, Hao Shen, Haifeng Pan, Zhenrong Sun, Junhao Chu, Xiang Yuan

Abstract: Magneto-infrared spectroscopy under strong magnetic fields provides a powerful probe of Landau quantization and field-induced collective excitations, yet its full potential has long been constrained by the lack of in-situ polarization control, because the highly divergent infrared beam propagating through narrow light tubes undergoes multiple wall reflections, leading to severe polarization degrad… ▽ More Magneto-infrared spectroscopy under strong magnetic fields provides a powerful probe of Landau quantization and field-induced collective excitations, yet its full potential has long been constrained by the lack of in-situ polarization control, because the highly divergent infrared beam propagating through narrow light tubes undergoes multiple wall reflections, leading to severe polarization degradation. Here we report a collimated magneto-infrared spectroscopy system that integrates continuous in-situ polarimetry. The system employs incident and exit collimation chambers forming a Kepler type optical architecture, which converts the large-aperture FTIR output into a low-divergence beam and strongly suppresses multi-reflection trajectories inside long gold-plated light tubes, thereby enhancing both optical throughput and polarization fidelity. A remotely controlled polarization module, consisting of an automated linear polarizer and a switchable Fresnel rhomb positioned entirely outside the high-field region, enables continuous in-situ tuning between linear, circular, and arbitrary elliptical polarization states without thermal cycling, manual realignment, or breaking vacuum. Interchangeable compact focusing modules further support Faraday and Voigt geometries in both transmission and reflection experiments within a 50 mm magnet bore, providing efficient beam focusing and signal collection while maintaining polarization fidelity. The setup achieves a minimum root-mean-square noise of 0.0033%, an average noise of 0.0082%, and a linear polarization extinction ratio up to 40:1. We demonstrate the capability through continuous in-situ linear polarimetry and broadband circular polarimetry in the magneto-infrared spectroscopy of various single crystals. This platform establishes a robust experimental framework for in-situ polarization-resolved magneto-infrared spectroscopy. △ Less

Submitted 1 July, 2026; originally announced July 2026.

Journal ref: Advanced Science Instruments,1(1),100005.(2026)

Giant and Broadband Circular Dichroism from Particle-Hole Symmetry Breaking in Weyl Semimetals

Authors: Xiangyu Jiang, Zeping Shi, Yuhan Du, Haonan Chen, Jiayu Wang, Wenbin Wu, Guangyi Wang, Congming Hao, Mingfan Yao, Mingsen Zhou, Xin Chen, Chenyao Xu, Zhongbo Yan, Cheng Zhang, Hai-Zhou Lu, Junhao Chu, Xiang Yuan

Abstract: Circular dichroism originates from symmetry breaking of material structure, leading to differential absorption of left- and right-circularly polarized light. However, circular dichroism in most materials is inherently weak and spectrally narrow, especially in the mid-to-far infrared. Here, we uncover giant infrared circular dichroism in the magnetic-field-forced Weyl semimetal Mn(Bi,Sb)2Te4, drive… ▽ More Circular dichroism originates from symmetry breaking of material structure, leading to differential absorption of left- and right-circularly polarized light. However, circular dichroism in most materials is inherently weak and spectrally narrow, especially in the mid-to-far infrared. Here, we uncover giant infrared circular dichroism in the magnetic-field-forced Weyl semimetal Mn(Bi,Sb)2Te4, driven by extreme particle-hole symmetry breaking. Helicity-resolved magneto-infrared spectroscopy reveals circular dichroism exceeding 3000 mdeg (~130 mdeg/nm) with above-degree response extending over the 6-13 μm spectral range. The optical resonances are enhanced by a strong band nesting effect intrinsic to the Landau levels of type-II Weyl dispersion. A symmetry-based kp model reproduces these magneto-infrared responses and demonstrates that magnetization-induced asymmetric spin-orbit coupling generates particle-hole symmetry breaking, suppressing spin-up, parity-even wavefunction components in the valence Landau band and thereby producing pronounced optical helicity selectivity. Our findings establish particle-hole symmetry breaking as an effective route toward helicity-resolved optical control in quantum materials. △ Less

Submitted 25 June, 2026; originally announced June 2026.

Journal ref: Nature Materials (2026)

Multistate Manipulation of Charge-Spin Conversion in Two-Dimensional Ferroelectric Bilayers

Authors: Weiyi Pan, Xinyuan Jiang, Jaroslav Fabian

Abstract: Achieving nonvolatile and multistate manipulation of charge-spin conversion, including the Edelstein effect (EE) and spin Hall effect (SHE), is crucial for high-density spintronic memory. Here, we propose a mechanism to simultaneously control both EE and SHE in two-dimensional ferroelectric bilayers, where interlayer-parallel and interlayer-antiparallel polarization configurations can coexist. Sym… ▽ More Achieving nonvolatile and multistate manipulation of charge-spin conversion, including the Edelstein effect (EE) and spin Hall effect (SHE), is crucial for high-density spintronic memory. Here, we propose a mechanism to simultaneously control both EE and SHE in two-dimensional ferroelectric bilayers, where interlayer-parallel and interlayer-antiparallel polarization configurations can coexist. Symmetry analysis shows that in the interlayer-parallel states, reversal of the total polarization switches the sign of the EE, whereas changing to an interlayer-antiparallel configuration suppresses the EE to zero, enabling electrically switchable current-induced spin accumulation among three distinct states, which could be used for ternary logic operations. Meanwhile, the magnitude of the SHE can be tuned by switching between two different classes of polarization configurations, namely interlayer-parallel and interlayer-antiparallel configurations. Using first-principles calculations, we demonstrate this mechanism in bilayer metallic ferroelectric PtBi2, where both interlayer-parallel and interlayer-antiparallel polarization configurations are energetically stable. The EE coefficient in interlayer-parallel states, which can be reversed by polarization switching, arises from competing electron- and hole-pocket contributions near the Fermi surface. The intrinsic SHE coefficients originate from spin Berry curvature that can be reshaped by polarization configuration variation and Fermi-level tuning. Our results establish ferroelectric bilayers as an all-in-one platform for electrically programmable charge-spin conversion. △ Less

Submitted 12 June, 2026; originally announced June 2026.

Non-equilibrium pathway to mesoscale ordering in ethanol-water binary liquid

Authors: Xinyue Jiang, Yating Shang, Jianhui Li, Zhaoyong Zou, Yanxia Zuo, Yuqun Xie

Abstract: Ethanol-water mixtures are a classic example of thermodynamic non-ideality, yet the structural origin of their pronounced anomalies, such as volume contraction and a large negative excess entropy, has remained a long-standing puzzle. Here, we demonstrate these anomalies are not equilibrium properties but calorimetric fingerprint of an arrested phase transition. By imposing periodic thermal oscilla… ▽ More Ethanol-water mixtures are a classic example of thermodynamic non-ideality, yet the structural origin of their pronounced anomalies, such as volume contraction and a large negative excess entropy, has remained a long-standing puzzle. Here, we demonstrate these anomalies are not equilibrium properties but calorimetric fingerprint of an arrested phase transition. By imposing periodic thermal oscillations, we drive a 50% (v/v) ethanol-water system along a complete hierarchical self-assembly pathway that progressed from ethanol clusters to water-containing droplets, then to acicular flakes, and finally to micron-scale ordered ethanol aggregates. Fluorescence spectroscopy, two-dimensional correlation analysis and nuclear magnetic resonance revealed the underlying non-equilibrium molecular mechanism: a periodic perturbation of the water-dominated hydrogen-bond network initiates a ethanol-water coexistence intermediate, ultimately leading to the stable ordered assembly of an ethanol-rich phase. Our finding demonstrated that periodic physical perturbations capable drive spontaneous ordering across multiple length scales in a simple binary mixture, providing a kinetic perspective on the structural origin of solution non-ideality, and carry general implications for self-assembly strategies in soft matter. △ Less

Submitted 25 May, 2026; originally announced May 2026.

Symmetry-Induced Relaxation Comb and Strong Quantum Mpemba Effect in Long-Range XXZ Spin Chains

Authors: Zijun Wei, Mingdi Xu, Yefeng Song, Xiang-Ping Jiang, Yangqian Yan, Lei Pan

Abstract: We uncover a symmetry-filtered mechanism for anomalous dissipative relaxation in a long-range XXZ spin chain subject to local dephasing. At the isotropic point, the coherent Hamiltonian has global $SU(2)$ symmetry, whereas the full Liouvillian retains only the $U(1)$ symmetry associated with total magnetization. This structure pins a family of spatially uniform zero-$U(1)$-charge left eigenoperato… ▽ More We uncover a symmetry-filtered mechanism for anomalous dissipative relaxation in a long-range XXZ spin chain subject to local dephasing. At the isotropic point, the coherent Hamiltonian has global $SU(2)$ symmetry, whereas the full Liouvillian retains only the $U(1)$ symmetry associated with total magnetization. This structure pins a family of spatially uniform zero-$U(1)$-charge left eigenoperators with exact eigenvalues $λ=-2q$, forming a Liouvillian relaxation comb. For the ferromagnetic Dicke ground state, the overlap envelope on this comb is known exactly at finite size and becomes Gaussian in the large-$S$ limit. Since higher-$q$ components decay rapidly, the $q=1$ comb tooth controls the long-time dynamics and yields universal $D(t)\sim e^{-2t}$ relaxation independent of system size and interaction range. This mode-accessibility filtering realizes a spectral strong quantum Mpemba effect: an initially farther state relaxes faster than closer thermal states because slow non-steady Liouvillian modes are inaccessible. Weak breaking of the Hamiltonian $SU(2)$ symmetry restores slow-mode overlap and suppresses this acceleration. △ Less

Submitted 28 July, 2026; v1 submitted 20 May, 2026; originally announced May 2026.

Switching between Antiferromagnetic and Ferromagnetic Skyrmions in Two-Dimensional Magnets

Authors: Xinyang Jiang, Jian Wu, Weiyi Pan

Abstract: Antiferromagnetic (AFM) and ferromagnetic (FM) skyrmions possess unique advantages for spintronic applications. AFM skyrmions eliminate the skyrmion Hall effect and exhibit fast dynamics, whereas FM skyrmions are easier to nucleate and manipulate. However, realizing a transition between AFM and FM skyrmions within the same two-dimensional (2D) material has remained elusive. Here, using first-princ… ▽ More Antiferromagnetic (AFM) and ferromagnetic (FM) skyrmions possess unique advantages for spintronic applications. AFM skyrmions eliminate the skyrmion Hall effect and exhibit fast dynamics, whereas FM skyrmions are easier to nucleate and manipulate. However, realizing a transition between AFM and FM skyrmions within the same two-dimensional (2D) material has remained elusive. Here, using first-principles calculations and atomistic spin simulations on the Janus monolayer Cr2Ge2Te3S3, we demonstrate that strain-driven modulation of magnetic interactions enables switching between AFM and FM skyrmion phases. A compressive strain of $-3\%$ induces an AFM ground state hosting AFM skyrmions, while a tensile strain of $+2\%$ drives the system into a FM skyrmion phase. Moreover, under an out-of-plane magnetic field, FM skyrmions are rapidly transformed into a uniform FM phase, while AFM skyrmions transform into AFM bimerons under stronger fields. These findings establish a framework for controllable transitions between topological magnetic states in a single 2D material. △ Less

Submitted 2 April, 2026; originally announced April 2026.

Chemical and optical control of chiral-domain dynamics in 1T-TaS$_2$

Authors: Qingzheng Qiu, Mengxian Zhao, Roman Mankowsky, Henrik Till Lemke, Serhane Zerdane, Mathias Sander, Zihao Tao, Qizhi Li, Xiquan Zheng, Shilong Zhang, Qian Xiao, Xinyi Jiang, Xin Liu, Shih-Wen Huang, Yang Yang, Sheng Meng, Yingying Peng

Abstract: Optical control of symmetry-breaking quantum phases is often constrained when one domain is strongly favored in equilibrium. This limitation is exemplified by the chiral charge-density-wave (CDW) order in 1T-TaS$_2$, where pristine samples predominantly select a single chirality. Here we show that free-energy landscape engineering through Ti substitution enables a distinct nonthermal pathway for u… ▽ More Optical control of symmetry-breaking quantum phases is often constrained when one domain is strongly favored in equilibrium. This limitation is exemplified by the chiral charge-density-wave (CDW) order in 1T-TaS$_2$, where pristine samples predominantly select a single chirality. Here we show that free-energy landscape engineering through Ti substitution enables a distinct nonthermal pathway for ultrafast chiral-domain redistribution. Ti doping stabilizes coexisting chiral domains and tunes their relative stability, allowing femtosecond excitation to drive an asymmetric and anisotropic redistribution from the dominant toward the minority chirality. The subpicosecond response follows a $\sim2$ THz amplitude mode and is consistent with a phonon-assisted pathway involving transient domain-wall configurations. Our results establish free-energy landscape engineering as a strategy for selecting nonequilibrium transition pathways. △ Less

Submitted 23 June, 2026; v1 submitted 24 March, 2026; originally announced March 2026.

Comments: 7 pages, 4 figures

Coupled Ferroelectricity and Phonon Chirality

Authors: Xiang-Bin Han, Cong Yang, Rui Sun, Xiaotong Zhang, Thuc Mai, Zhengze Xu, Aryan Jouneghaninaseri, Xiaoning Jiang, Rahul Rao, Yi Xia, Dali Sun, Jun Liu, Xiaotong Li

Abstract: The ability to control chirality and chiral phonons offers a route to manipulate the direction of spin and angular-momentum transport. In materials with rigid structural chirality, such as quartz, phonon chirality is fixed by the handedness and cannot be switched. By contrast, ferroelectric materials host a spontaneous polarization that can be reversibly switched by an external electric field. Whe… ▽ More The ability to control chirality and chiral phonons offers a route to manipulate the direction of spin and angular-momentum transport. In materials with rigid structural chirality, such as quartz, phonon chirality is fixed by the handedness and cannot be switched. By contrast, ferroelectric materials host a spontaneous polarization that can be reversibly switched by an external electric field. When chirality is coupled to this ferroelectric polarization, it enables electrical switching of crystal chirality and the associated phonon angular momentum, which is compatible with solid-state spintronic architectures, enabling control over chirality-dependent quantum states.1 Here, we report the experimental demonstration of the coupling between ferroelectricity and phonon chirality in the molecular ferroelectric triglycine sulfate. By electrically switching the crystal chirality, we achieve reversible and device-compatible control of phonon chirality, as revealed by in situ time-resolved magneto-optical Kerr effect measurements. The Kerr rotation reverses with electric-field switching, while phonon chirality vanishes in the paraelectric phase and is tunable in the racemic ferroelectric state. Furthermore, density functional theory calculations and circularly polarized Raman spectroscopy further corroborate the opposite circular phonon motions. These results establish an electrically addressable coupling pathway linking ferroelectricity, structural chirality, chiral phonons, and spin, opening a route toward chiral-phonon-enabled spin and phonon control technologies based on ferroelectric materials. △ Less

Submitted 13 March, 2026; originally announced March 2026.

Polarization Engineering of Second-Harmonic Generation in 3R-MoS$_2$ Waveguides

Authors: Renkang Song, Junbo Xu, Yanzhen Yin, Yu Yin, Xu Jiang, Zhichen Zhao, Lei Zhou, Jintian Lin, Gaozhong Wang, Vasily Kravstov, Kyoung-Duck Park, Ivan Iorsh, Yuerui Lu, Jun Wang, Guangwei Hu, Zhanshan Wang, Di Huang, Tao Jiang

Abstract: Chip-scale nonlinear optics enables strong light-matter interactions within compact devices, serving as a fundamental platform for multifunctional integrated photonics from classical optical signal processing to quantum information technologies. Transition metal dichalcogenide (TMDC) waveguides have recently emerged as a highly promising platform owing to their giant material nonlinearity and exte… ▽ More Chip-scale nonlinear optics enables strong light-matter interactions within compact devices, serving as a fundamental platform for multifunctional integrated photonics from classical optical signal processing to quantum information technologies. Transition metal dichalcogenide (TMDC) waveguides have recently emerged as a highly promising platform owing to their giant material nonlinearity and extended interaction lengths. To date, however, research has predominantly focused on conversion efficiency, leaving the mechanisms governing the polarization state of nonlinear signal largely unexplored. Here, we establish a comprehensive framework for engineering the polarization of second-harmonic generation (SHG) in 3R-MoS$_2$ waveguides. By synergizing polarization-resolved measurements with theoretical modeling, we reveal that the SHG polarization is determined by guided-mode interactions constrained by waveguide geometry and crystal symmetry, and further reshaped during propagation. We demonstrate that thickness-dependent guided-mode confinement and in-plane crystal symmetry provide robust, static control over SHG polarization, while propagation length offers a dynamic tuning knob for continuously tailoring the nonlinear output. Our findings provide a deterministic approach for on-chip polarization engineering, opening opportunities for reconfigurable nonlinear light sources and quantum photonic circuits. △ Less

Submitted 28 February, 2026; originally announced March 2026.

Comments: 15 pages, 4 figures

Dissipative charging of tight-binding quantum batteries

Authors: Mingdi Xu, Yiming Liu, Yefeng Song, Xiang-Ping Jiang, Lei Pan

Abstract: We investigate autonomous dissipative charging mechanisms for lattice quantum batteries within the framework of open quantum systems. Focusing on engineered Markovian dissipation, we show that appropriately designed Lindblad jump operators can drive tight-binding systems into highly excited band-edge states, resulting in steady states with large ergotropy. We illustrate this mechanism in a one-dim… ▽ More We investigate autonomous dissipative charging mechanisms for lattice quantum batteries within the framework of open quantum systems. Focusing on engineered Markovian dissipation, we show that appropriately designed Lindblad jump operators can drive tight-binding systems into highly excited band-edge states, resulting in steady states with large ergotropy. We illustrate this mechanism in a one-dimensional tight-binding chain and in a two-dimensional graphene lattice. We find that disorder enhances the charging power, indicating that dissipation-assisted localization effects can be beneficial for energy storage. Moreover, the dissipative charging process remains robust against additional local dephasing noise. Our results establish bond dissipation as an effective and physically transparent mechanism for charging lattice quantum batteries in realistic open-system settings. △ Less

Submitted 24 March, 2026; v1 submitted 19 February, 2026; originally announced February 2026.

Comments: 10 pages, 5 figures, comments are welcome

Quantum Pontus--Mpemba Effect in Dissipative Quasiperiodic Chains

Authors: Yefeng Song, Junxiao Chen, Xiangyu Yang, Mingdi Xu, Xiang-Ping Jiang, Lei Pan

Abstract: We investigate how quasiperiodic spatial structure enables protocol-induced acceleration in open quantum systems by analyzing the Pontus-Mpemba effect in one-dimensional chains subject to Markovian dephasing. The dynamics are governed by a Lindblad superoperator that drives all initial states toward a maximally mixed infinite-temperature steady state, isolating dynamical mechanisms from static equ… ▽ More We investigate how quasiperiodic spatial structure enables protocol-induced acceleration in open quantum systems by analyzing the Pontus-Mpemba effect in one-dimensional chains subject to Markovian dephasing. The dynamics are governed by a Lindblad superoperator that drives all initial states toward a maximally mixed infinite-temperature steady state, isolating dynamical mechanisms from static equilibrium properties. Considering two representative quasiperiodic models, namely a tight-binding chain with a mosaic potential and its extension with power-law long-range hopping, we show that a properly engineered two-step protocol, in which the system is first steered to a finite temperature intermediate state, yields a strictly shorter overall relaxation time than direct evolution from the same initial configuration. This protocol-induced acceleration persists for both initially localized and extended eigenstates and remains robust in the presence of long-range hopping. A Liouvillian spectral analysis reveals that the mechanism originates from a redistribution of spectral weight that suppresses overlap with the slowest decay modes, rather than from any modification of the decay spectrum itself. Our results establish quasiperiodic chains as a controlled setting for engineering relaxation pathways through Liouvillian spectral structure. △ Less

Submitted 17 February, 2026; originally announced February 2026.

Comments: All comments are welcome!

Inverse orbital Hall effect induced terahertz emission enabled by a ferromagnet with quenched orbital moment in Fe/Pt/W trilayers

Authors: Chao Zhou, Lei Hao, Shaohua Zhang, Yaxuan Jin, Xianguo Jiang, Ning Yang, Li Zheng, Hao Meng, Chao Lu, Wendeng Huang, Yizheng Wu, Yan Zhou, Jia Xu

Abstract: The inverse orbital Hall effect (IOHE) has recently attracted considerable attention as an emerging mechanism for terahertz (THz) emission based on ultrafast angular-momentum-to-charge conversion. Most experimental studies have focused on materials with strong spin-orbit coupling or pronounced orbital character, where sizable orbital Hall responses are expected. Elemental ferromagnets such as Fe a… ▽ More The inverse orbital Hall effect (IOHE) has recently attracted considerable attention as an emerging mechanism for terahertz (THz) emission based on ultrafast angular-momentum-to-charge conversion. Most experimental studies have focused on materials with strong spin-orbit coupling or pronounced orbital character, where sizable orbital Hall responses are expected. Elemental ferromagnets such as Fe are generally regarded as quenched orbital sources and are not expected to exhibit orbital-dominated THz emission. Here, we report a pronounced enhancement of THz emission in Fe/Pt/W trilayer heterostructures, despite the absence of detectable orbital contributions in the corresponding Fe/Pt and Fe/W bilayers. Thickness-dependent measurements reveal long-distance signal persistence, systematic delay accumulation, and pronounced pulse broadening with increasing W thickness. These features are inconsistent with diffusive spin transport and indicate that orbital angular momentum transport in the W layer, converted into charge current via the IOHE, becomes a dominant channel for THz emission in the trilayer configuration. Our results demonstrate that strong IOHE can emerge in heterostructures incorporating a quenched orbital ferromagnet, providing an effective route to enhance spintronic THz emitters through orbital Hall physics. △ Less

Submitted 9 February, 2026; originally announced February 2026.

Comments: 19 pages, 4 figures

Maximal Entanglement and Frozen Information: A Unified Framework for Dynamical Quantum Phase Transitions

Authors: Kaiyuan Cao, Mingzhi Li, Xiang-Ping Jiang, Shu Chen, Jian Wang

Abstract: Dynamical quantum phase transitions (DQPTs) are temporal singularities marked by zeros of the Loschmidt echo, yet their underlying quantum-information structure remains elusive. Here, we introduce a momentum-resolved entanglement entropy as a direct probe of DQPTs in translation-invariant free systems. We analytically establish that every critical momentum mode $k^{*}$ associated with a DQPT satur… ▽ More Dynamical quantum phase transitions (DQPTs) are temporal singularities marked by zeros of the Loschmidt echo, yet their underlying quantum-information structure remains elusive. Here, we introduce a momentum-resolved entanglement entropy as a direct probe of DQPTs in translation-invariant free systems. We analytically establish that every critical momentum mode $k^{*}$ associated with a DQPT saturates its entanglement to the maximal value $\ln{2}$, coinciding with the vanishing of the Loschmidt echo. Crucially, we demonstrate that this maximal entanglement universally suppresses information scrambling: a momentum-resolved out-of-time-ordered correlator (OTOC) vanishes identically for all times at $k^{*}$. These three signatures -- Fisher zeros, maximal entanglement, and vanished OTOC -- are proved to be equivalent in both the transverse-field Ising and Su-Schrieffer-Heeger models, despite their distinct bipartitions (momentum-pair vs. sublattice). Our results establish a unified, information-theoretic framework for DQPTs, revealing them a points where quantum correlations saturate and information flow halts. This work elevates entanglement and scrambling to central dynamical order parameters, offering a universal perspective on nonequilibrium quantum critically. △ Less

Submitted 20 January, 2026; v1 submitted 7 January, 2026; originally announced January 2026.

Comments: 7 pages,1 figure

Tailoring Dynamical Quantum Phase Transitions via Double-Mode Squeezing Manipulation

Authors: Kaiyuan Cao, Haodong Wang, Xiang-Ping Jiang, Shu chen, Jian Wang

Abstract: We propose a protocol to tailor dynamical quantum phase transitions (DQPTs) by double-mode squeezing onto the initial state in the XY chain. The effect of squeezing depends critically on the system's symmetry and parameters. When the squeezing operator breaks particle-hole symmetry (PHS), DQPTs become highly tunable, allowing one to either induce transitions within a single phase or suppress them.… ▽ More We propose a protocol to tailor dynamical quantum phase transitions (DQPTs) by double-mode squeezing onto the initial state in the XY chain. The effect of squeezing depends critically on the system's symmetry and parameters. When the squeezing operator breaks particle-hole symmetry (PHS), DQPTs become highly tunable, allowing one to either induce transitions within a single phase or suppress them. Remarkably, when PHS is preserved and the squeezing strength reaches $r=π/4$, a universal class of DQPTs emerges, independent of the quench path. This universality is characterized by two key features: (i) the collapse of all Fisher zeros onto the real-time axis, and (ii) the saturation of intermode entanglement to its maximum in each $(k,-k)$ modes. Moreover, the critical momenta governing the DQPTs coincide exactly with the modes attaining the maximal entanglement. At this universal point, the dynamical phase vanishes, leading to a purely geometric evolution marked by $π$-jumps in the Pancharatnam geometric phase. Our work establishes initial-state squeezing as a versatile tool for tailoring far-from-equilibrium criticality and reveals a direct link between entanglement saturation and universal nonanalytic dynamics. △ Less

Submitted 6 January, 2026; originally announced January 2026.

Comments: 7 pages, 4 figures

Defect Engineering for Stabilizing Magnetic and Topological Properties in Mn(Bi1-xSbx)2Te4

Authors: Haonan Chen, Jiayu Wang, Huayao Li, Xunkai Duan, Yuxiang Wang, Zixuan Xu, Yingchao Xia, Wenhao He, Zehao Jia, Xiangyu Cao, Yicheng Mou, Xiangyu Jiang, Jiaming Gu, Pengliang Leng, Fengfeng Zhu, Changlin Zheng, Xiang Yuan, Faxian Xiu, Tong Zhou, Lin Miao, Cheng Zhang

Abstract: MnBi2Te4 is a versatile platform for exploring diverse topological quantum states, yet its potential is hampered by intrinsic antisite defects. While Sb substitution has been employed to tune the Fermi level towards the charge neutral point, it exacerbates the formation of Mn-Sb antisite defects. Here, we address this challenge by combining first-principles calculations with strategic synthesis to… ▽ More MnBi2Te4 is a versatile platform for exploring diverse topological quantum states, yet its potential is hampered by intrinsic antisite defects. While Sb substitution has been employed to tune the Fermi level towards the charge neutral point, it exacerbates the formation of Mn-Sb antisite defects. Here, we address this challenge by combining first-principles calculations with strategic synthesis to systematically investigate and control antisite defects in Mn(Bi1-xSbx)2Te4. Our calculations reveal that increasing antisite defect density progressively destroys the field-forced magnetic Weyl state, eventually driving the system into a trivial magnetic insulator. Motivated by these findings, we develop an optimized chemical vapor transport method, yielding high-quality Mn(Bi1-xSbx)2Te4 crystals with significantly reduced antisite defect density. The emergence of strong Shubnikov-de Haas oscillations in the forced ferromagnetic state and a pronounced anomalous Hall effect near charge neutrality, with opposite signs for n- and p-type samples, confirms the type-II Weyl semimetal nature. These findings underscore the critical role of antisite defects in determining the magnetic and topological properties of Mn(Bi1-xSbx)2Te4 and establish defect engineering via optimized synthesis as a crucial strategy for realizing its exotic magnetic topological states. △ Less

Submitted 25 December, 2025; originally announced December 2025.

Comments: 26 pages, 8 figures

Spin and Orbital Angular Momentum Polarization in Thouless Topological Charge Pumping

Authors: Esmaeil Taghizadeh Sisakht, Uiseok Jeong, Xiao jiang, Jinseok Oh, Yizhou Liu, Binghai Yan, Noejung Park

Abstract: Quantized charge pumping in one-dimensional chiral wires has been widely studied in the context of topological physics in a (1+1)-dimensional synthetic space, yet the role of orbital and spin degrees of freedom in such topological pumps remains largely unexplored. Here, we examine how the topologically quantized charge pump in insulators generates spin polarizations, and assess whether this mechan… ▽ More Quantized charge pumping in one-dimensional chiral wires has been widely studied in the context of topological physics in a (1+1)-dimensional synthetic space, yet the role of orbital and spin degrees of freedom in such topological pumps remains largely unexplored. Here, we examine how the topologically quantized charge pump in insulators generates spin polarizations, and assess whether this mechanism may offer distinct insight into the widely known spin-selective transport in chiral wires-commonly referred to as chirality-induced spin selectivity. We performed time-dependent Schrodinger equations of multi-orbital tight-binding Hamiltonians driven by a circularly polarized electric field. Our main findings are twofold. First, the intrinsic screw-like geometry of the system generates a distinctive winding structure governed by a single control parameter, in contrast to conventional adiabatic pumping mechanisms that require at least two independently modulated parameters, thereby providing a clear interpretation of one-dimensional pumping in terms of the topological structure in a (1+1)-dimensional Brillouin zone. Second, while the energy gap remains open throughout the pumping cycle, the Berry-phase driven real-time dynamics of the charge flow induces a nonequilibrium orbital polarization. Through spin-orbit coupling, this orbital response is partially converted into spin polarization whose direction is determined by the current and chirality. On the analogy between the synthetic (1+1)- and 2-dimensional topological insulators, we suggest that non-trivial spin-orbital dynamics may accompany the anomalous quantum charge Hall states of even-dimensional real materials. △ Less

Submitted 23 December, 2025; originally announced December 2025.

A High-Flux and High-Efficiency Setup for Magneto-Infrared Spectroscopy

Authors: Zeping Shi, Wenbin Wu, Zhiwei Zhang, Yuhan Du, Chenyao Xu, Guangyi Wang, Mingsen Zhou, Congming Hao, Xianghao Meng, Xiangyu Jiang, Chunhui Pan, Wei Lu, Hao Shen, Haifeng Pan, Zhenrong Sun, Junhao Chu, Xiang Yuan

Abstract: We report the design and implementation of a high-flux, high-efficiency magneto-infrared spectroscopy system optimized for broadband measurements in high magnetic fields. The setup integrates a Fourier transform infrared spectrometer, a 12 T cryogen-free superconducting magnet, precision-polished and gold-plated light tubes, custom-designed reflective focusing modules for Faraday and Voigt geometr… ▽ More We report the design and implementation of a high-flux, high-efficiency magneto-infrared spectroscopy system optimized for broadband measurements in high magnetic fields. The setup integrates a Fourier transform infrared spectrometer, a 12 T cryogen-free superconducting magnet, precision-polished and gold-plated light tubes, custom-designed reflective focusing modules for Faraday and Voigt geometries, and an external multi-detector chamber with motorized selection. Optical throughput is maximized by reducing light tube loss from 65.5%/m to 22.0%/m via abrasive flow and mechanical polishing followed by gold electroplating, and by adopting a single-on-axis parabolic-mirror Faraday module that increases the effective numerical aperture from 0.14 to 0.36, enhancing collection efficiency by nearly an order of magnitude. An eight-position motorized sample stage and fully automated control over magnetic field, temperature, optical path, and detector choice enable high-throughput measurements without repeated warm-ups. The optimized configuration achieves a root-mean-square noise level of 0.0061% in a 2-minute integration for a 40% reflectivity sample, corresponding to a signal-to-noise ratio exceeding 16000. System capabilities are demonstrated by resolving weak replica bands in EuCd2As2 and faint Landau level transitions in LaAlSi. △ Less

Submitted 16 December, 2025; originally announced December 2025.

Journal ref: Rev. Sci. Instrum. 96, 113902 (2025)

Isotropic Dirac fermion and anomalous oscillator strength of zeroth Landau level transition

Authors: Zeping Shi, Wenbin Wu, Guangyi Wang, Mykhaylo Ozerov, Jian Yuan, Wei Xia, Yuhan Du, Xianghao Meng, Xiangyu Jiang, Mingsen Zhou, Yuxi Chen, Hao Shen, Yanfeng Guo, Junhao Chu, Xiang Yuan

Abstract: Dirac fermions, characterized by their linear dispersion and relativistic nature, have emerged as a prominent class of quasiparticles in condensed matter physics. While the Dirac equation, initially developed in the context of high-energy physics, provides a remarkable framework for describing the electronic properties of these materials, the inherent symmetry constraints of condensed matter often… ▽ More Dirac fermions, characterized by their linear dispersion and relativistic nature, have emerged as a prominent class of quasiparticles in condensed matter physics. While the Dirac equation, initially developed in the context of high-energy physics, provides a remarkable framework for describing the electronic properties of these materials, the inherent symmetry constraints of condensed matter often lead to deviations from the idealized paradigm. In particular, three-dimensional Dirac fermions in solids often exhibit anisotropic behavior, challenging the notion of perfect symmetry inherent in the Dirac equation. Here, we report the observation of isotropic massive Dirac fermions in LaAlSi through Landau level spectroscopy. The presence of three-dimensional massive Dirac fermions across the Fermi energy is demonstrated by quantized and semiclassical analyses of the magnetic field evolution of Landau level transitions. The isotropic topological nature, Fermi velocity, and Dirac mass are evidenced by the identical magneto-infrared response among the Faraday and three Voigt geometries. Furthermore, we observe an unusually large oscillator strength in the zeroth Landau level transition of the Dirac fermion, compared to transitions with higher indices. This phenomenon, supported by model calculations, can be attributed to the combined effects of the partial excitation of Dirac fermion and the resonant dielectric coupling with the Weyl plasma. Our work provides a strategy for realizing ideal quasiparticle excitations and their coupling effects in condensed matter systems, offering a platform for exploring relativistic physics. △ Less

Submitted 16 December, 2025; originally announced December 2025.

Journal ref: Communications Physics, 8, 376. (2025) Communications Physics, 8, 376. (2025) Communications Physics, 8, 376. (2025) Communications Physics, 8, 376. (2025)

Two-dimensional helical superconductivity and gapless superconducting edge modes in the 1T$^\prime$-WS$_2$/2H-WS$_2$ heterophase bilayer

Authors: Xuance Jiang, Jennifer Cano, Yuan Ping, Yafis Barlas, Deyu Lu

Abstract: We propose a material platform comprised of transition metal dichalcogenide (TMDC) heterostructures to realize the two-dimensional (2D) helical superconductivity with an intrinsic gap. By van der Waals stacking a 2D superconductor (1T$^\prime$-WS$_2$ with inversion symmetry) on top of a 2D topological insulator (2H-WS$_2$ with mirror symmetry), the resulting TMDC bilayer exhibits Rashba supercondu… ▽ More We propose a material platform comprised of transition metal dichalcogenide (TMDC) heterostructures to realize the two-dimensional (2D) helical superconductivity with an intrinsic gap. By van der Waals stacking a 2D superconductor (1T$^\prime$-WS$_2$ with inversion symmetry) on top of a 2D topological insulator (2H-WS$_2$ with mirror symmetry), the resulting TMDC bilayer exhibits Rashba superconductivity. Under an external in-plane magnetic field, the system can host finite-momentum Cooper pairing, evidenced by the divergence in the particle-particle susceptibility of a $k\cdot p$ Hamiltonian fitted to the \textit{ab initio} theory band structure. The resulting 2D helical superconducting phase can induce superconductivity in the edge states with its spatially varying order parameter. By varying the strength of the in-plane magnetic field, we demonstrate that the helical edge state can undergo a phase transition to a one-dimensional gapless phase with narrow Fermi segments corresponding to zero-energy Bogoliubov quasi-particles. The controllable one-dimensional gapless phase serves as a clear experimental fingerprint of 2D helical superconductivity. The proposed 2D TMDC heterostructure is promising for intrinsic nonreciprocal superconducting transport and the development of Majorana-based quantum devices. △ Less

Submitted 10 December, 2025; originally announced December 2025.

Journal ref: Phys. Rev. B 114, L020507 (2026)

Potential-Programmed Operando Ensembles Govern Nitrate Electroreduction

Authors: Xue-Chun Jiang, Jia-Lan Chen, Wei-Xue Li, Jin-Xun Liu

Abstract: Electrocatalyst surfaces continuously reorganize on the timescale of catalytic turnover, obscuring the identification of active sites under operando conditions and hindering rational catalyst design. Here, we resolve the operando Cu(111) electrolyte interface for nitrate-to-ammonia electroreduction (NO3RR) via a multiscale modeling framework accelerated by a coverage-aware machine-learning potenti… ▽ More Electrocatalyst surfaces continuously reorganize on the timescale of catalytic turnover, obscuring the identification of active sites under operando conditions and hindering rational catalyst design. Here, we resolve the operando Cu(111) electrolyte interface for nitrate-to-ammonia electroreduction (NO3RR) via a multiscale modeling framework accelerated by a coverage-aware machine-learning potential. Rather than a single "average coverage" site, the working interface is a potential-gated statistical ensemble of 34 interconverting adsorbate motifs between -0.10 and -1.00 V (vs. SHE). Potential-driven shifts in motif populations produce a volcano-shaped activity trend peaking at -0.70 V, where the site-normalized turnover frequency reaches 0.015 s-1 with nearly 100% Faradaic efficiency to ammonia. The activation barriers across >150 transition states collapse into a single linear relationship with the excess charge on the reacting Cu atoms (ΔqCu), identifying interfacial charge redistribution as a unifying kinetic descriptor. The maximum activity arises not from uniform moderate coverage but from a 2NO/2NH2 quadrilateral microensemble that tunes ΔqCu to an intermediate value, simultaneously lowering the N-O cleavage and N-H formation barriers. Reconceptualizing "coverage" as an ensemble of local microenvironments decouples thermodynamic stability from catalytic productivity. This perspective furnishes a parameter-free strategy by controlling motif populations and interfacial charge via the potential to program high-coverage electrocatalysis beyond the NO3RR. △ Less

Submitted 12 November, 2025; originally announced November 2025.

Comments: 6 figures

Krylov Complexity Meets Confinement

Authors: Xuhao Jiang, Jad C. Halimeh, N. S. Srivatsa

Abstract: In high-energy physics, confinement denotes the tendency of fundamental particles to remain bound together, preventing their observation as free, isolated entities. Interestingly, analogous confinement behavior emerges in certain condensed matter systems, for instance, in the Ising model with both transverse and longitudinal fields, where domain walls become confined into meson-like bound states a… ▽ More In high-energy physics, confinement denotes the tendency of fundamental particles to remain bound together, preventing their observation as free, isolated entities. Interestingly, analogous confinement behavior emerges in certain condensed matter systems, for instance, in the Ising model with both transverse and longitudinal fields, where domain walls become confined into meson-like bound states as a result of a longitudinal field-induced linear potential. In this work, we employ the Ising model to demonstrate that Krylov state complexity--a measure quantifying the spread of quantum information under the repeated action of the Hamiltonian on a quantum state--serves as a sensitive and quantitative probe of confinement. We show that confinement manifests as a pronounced suppression of Krylov complexity growth following quenches within the ferromagnetic phase in the presence of a longitudinal field, reflecting slow correlation dynamics. In contrast, while quenches within the paramagnetic phase exhibit enhanced complexity with increasing longitudinal field, reflecting the absence of confinement, those crossing the critical point to the ferromagnetic phase reveal a distinct regime characterized by orders-of-magnitude larger complexity and display trends of weak confinement. Notably, in the confining regime, the complexity oscillates at frequencies corresponding to the meson masses, with its power-spectrum peaks closely matching the semiclassical predictions. △ Less

Submitted 19 February, 2026; v1 submitted 5 November, 2025; originally announced November 2025.

Comments: 5 pages, 5 figures, Supplemental Material

Journal ref: Phys. Rev. D 113, L031503 (2026)

Switching between Skyrmions and Yoshimori Spin Spirals via Li Absorption in Janus Magnets

Authors: Xinyuan Jiang, Jian Wu, Weiyi Pan

Abstract: Chiral magnetic textures have attracted considerable attention owing to their topological properties and potential applications in spintronic devices. Here, we employ first-principles calculations together with atomic spin dynamics simulations to explore the switching between skyrmions and Yoshimori-type spin spirals induced by Li adsorption in Janus two-dimensional (2D) CrTeSe. We show that selec… ▽ More Chiral magnetic textures have attracted considerable attention owing to their topological properties and potential applications in spintronic devices. Here, we employ first-principles calculations together with atomic spin dynamics simulations to explore the switching between skyrmions and Yoshimori-type spin spirals induced by Li adsorption in Janus two-dimensional (2D) CrTeSe. We show that selective Li adsorption on either the Se- or Te-terminated surface stabilizes distinct magnetic phases: Li adsorption on the Se side favors a Yoshimori-type spin spiral, whereas adsorption on the Te side stabilizes the skyrmionic state. This contrast originates from site-dependent modifications of exchange interactions, magnetic anisotropy (MA), and the Dzyaloshinskii-Moriya interaction (DMI). In addition, the response of magnetic textures to out-of-plane magnetic fields differs strongly between the two systems. These results demonstrate that surface adsorption provides an effective strategy for reversible control of chiral magnetic states in 2D magnets, while also offering fundamental insights into the competing interactions that govern the stability of skyrmions and Yoshimori spin spirals. Our findings highlight the potential of Janus 2D materials as a versatile platform for engineering tunable spintronic devices. △ Less

Submitted 26 October, 2025; originally announced October 2025.

Altermagnetism induced surface Chern insulator

Authors: Xuance Jiang, Sayed Ali Akbar Ghorashi, Deyu Lu, Jennifer Cano

Abstract: We propose a new pathway to the quantized anomalous Hall effect (QAHE) by coupling an altermagnet to a topological crystalline insulator (TCI). The former gaps the topological surface states of the TCI, thereby realizing the QAHE in a robust and switchable platform with near- vanishing magnetization. We demonstrate the feasibility of this approach by studying a slab of the TCI SnTe coupled to an a… ▽ More We propose a new pathway to the quantized anomalous Hall effect (QAHE) by coupling an altermagnet to a topological crystalline insulator (TCI). The former gaps the topological surface states of the TCI, thereby realizing the QAHE in a robust and switchable platform with near- vanishing magnetization. We demonstrate the feasibility of this approach by studying a slab of the TCI SnTe coupled to an altermagnetic RuO2 layer. Our first-principles calculations reveal that the d-wave altermagnetism in RuO2 induces a 7 meV gap to the Dirac surface states on the (110) surface of SnTe, producing a finite anomalous Hall effect. Our approach generalizes to broader classes of altermagnetic materials and TCIs, thereby providing a family of topological altermagnetic heterostructures with small or vanishing magnetization that support nontrivial Chern numbers. Our results highlight a promising new topological platform with great tunability and applications to spintronics. △ Less

Submitted 17 October, 2025; originally announced October 2025.

Advancing AI-Driven Analysis in X-ray Absorption Spectroscopy: Spectral Domain Mapping and Universal Models

Authors: Nina Cao, Pavan Ravindra, Shubha R. Kharel, Chuntian Cao, Boyang Li, Xuance Jiang, Matthew R. Carbone, Xiaohui Qu, Deyu Lu

Abstract: In recent years, rapid progress has been made in developing artificial intelligence (AI) and machine learning (ML) methods for x-ray absorption spectroscopy (XAS) analysis. Compared to traditional XAS analysis methods, AI/ML approaches offer dramatic improvements in efficiency and help eliminate human bias. To advance this field, we advocate an AI-driven XAS analysis pipeline that features several… ▽ More In recent years, rapid progress has been made in developing artificial intelligence (AI) and machine learning (ML) methods for x-ray absorption spectroscopy (XAS) analysis. Compared to traditional XAS analysis methods, AI/ML approaches offer dramatic improvements in efficiency and help eliminate human bias. To advance this field, we advocate an AI-driven XAS analysis pipeline that features several inter-connected key building blocks: benchmarks, workflows, databases, and AI/ML models. Specifically, we present two case studies for XAS ML. In the first study, we demonstrate the importance of reconciling the discrepancies between simulation and experiment using spectral domain mapping (SDM). Our ML model, which is trained solely on simulated spectra, predicts an incorrect oxidation state trend for Ti atoms in a combinatorial zinc titanate film. After transforming the experimental spectra into a simulation-like representation using SDM, the same model successfully recovers the correct oxidation state trend. In the second study, we explore the development of universal XAS ML models that are trained on the entire periodic table, which enables them to leverage common trends across elements. Looking ahead, we envision that an AI-driven pipeline can unlock the potential of real-time XAS analysis to accelerate scientific discovery. △ Less

Submitted 16 October, 2025; originally announced October 2025.

Nontrivial topology in one- and two-dimensional asymmetric systems with chiral boundary states

Authors: Yunlin Li, Yufu Liu, Xuezhi Wang, Haoran Zhang, Xunya Jiang

Abstract: Symmetry plays an important role in the topological band theory. In contrary, study on the topological properties of the asymmetric systems is rather limited, especially in higher-dimensional systems. In this work, we explore a new theory to study the topology in various one-dimensional (1D) and two-dimensional (2D) asymmetric systems with chiral boundary states. Starting from the simple SSHm mode… ▽ More Symmetry plays an important role in the topological band theory. In contrary, study on the topological properties of the asymmetric systems is rather limited, especially in higher-dimensional systems. In this work, we explore a new theory to study the topology in various one-dimensional (1D) and two-dimensional (2D) asymmetric systems with chiral boundary states. Starting from the simple SSHm model, we show the chiral topology of its edge states by redefining sublattices. Meanwhile, based on its Rice-Mele-like effective Hamiltonian, a new topological invariant $\bar{Z}$ can be defined and the bulk-edge correspondence is established. With this clear physical picture, our theory can be extended to the more complex asymmetric ladder models, or even the 2D asymmetric systems. In the 2D BBH3 model, new chiral corner states with redefined lattices are found based on our method. These corner states are independent of any spatial symmetry and exhibit the characteristics of topological bound states in the continuum (TBICs). Moreover, the topological invariant can be calculated by introducing $\bar{Z}$ into 2D. At last, we propose an acoustic experiment of the BBH3 model where chiral corner states are numerically observed. Our work exhibits a new approach to study the topological properties of asymmetric systems. By redefining sublattices, we find that the models with entirely different structures might share the same topological origins. △ Less

Submitted 25 September, 2025; originally announced September 2025.

Cost Reduction in Spin-dependent Stochastic GW Calculations

Authors: Xuance Jiang, Vojtech Vlcek

Abstract: We extend the stochastic GW (sGW) formalism to fully spin-polarized systems, encompassing both collinear and non-collinear spin configurations. For non-collinear systems-where Kohn-Sham states are complex two-component spinors-we develop a complex-valued stochastic basis that preserves the real-valued external stochastic charge applied at time zero. This basis enables an unbiased evaluation of the… ▽ More We extend the stochastic GW (sGW) formalism to fully spin-polarized systems, encompassing both collinear and non-collinear spin configurations. For non-collinear systems-where Kohn-Sham states are complex two-component spinors-we develop a complex-valued stochastic basis that preserves the real-valued external stochastic charge applied at time zero. This basis enables an unbiased evaluation of the random-phase approximation (RPA) screened interaction for spinors. Through error analysis and tests on real materials, we show that the performance of collinear sGW retains the same time complexity as the spin-unpolarized sGW . The non-collinear sGW incurs a computational cost two to three times higher than the spin-unpolarized version, while preserving linear scaling with low multiplicity. By unifying collinear and non-collinear treatments within a single scalable framework, our work paves the way for routine many-body predictions in large scale magnetic and spin-orbit-coupled material systems. △ Less

Submitted 24 September, 2025; v1 submitted 18 September, 2025; originally announced September 2025.

Dissipation-Enhanced Localization in a Disorder-Free $\mathbb{Z}_2$ Lattice Gauge System

Authors: Xuanpu Yang, Xiang-Ping Jiang, Lei Pan

Abstract: The $\mathbb{Z}_2$ lattice gauge model, as the simplest realization of a lattice gauge theory, exhibits rich and unconventional physics. One of its most remarkable features is disorder-free localization, where localization emerges not from explicit quenched disorder but from static background $\mathbb{Z}_2$ gauge charges, leading to persistent memory of the initial state. In this work, we investig… ▽ More The $\mathbb{Z}_2$ lattice gauge model, as the simplest realization of a lattice gauge theory, exhibits rich and unconventional physics. One of its most remarkable features is disorder-free localization, where localization emerges not from explicit quenched disorder but from static background $\mathbb{Z}_2$ gauge charges, leading to persistent memory of the initial state. In this work, we investigate the dissipative dynamics of the $\mathbb{Z}_2$ lattice gauge model by coupling it to a Markovian environment. We find that quantum dissipation can enhance localization: memory of the initial state is retained more robustly under dissipative evolution than under unitary dynamics. This dissipation-induced enhancement of localization persists across a variety of initial states, indicating that the effect is not limited to fine-tuned configurations. Our results demonstrate that dissipation, often associated with decoherence and thermalization, can in fact serve as a powerful tool for stabilizing non-ergodic behavior in gauge-constrained quantum systems. △ Less

Submitted 8 September, 2025; originally announced September 2025.

Comments: 9 pages, 5 figures, comments are welcome

Correlation-driven 3d Heavy Fermion behavior in LiV2O4

Authors: Min-Yi-Nan Lei, Z. H. Chen, H. T. Wang, Y. Fan, N. Guo, T. X. Jiang, Yanwei Cao, T. Zhang, Rui Peng, Haichao Xu

Abstract: LiV2O4 is a spinel-structured compound that stands out as the first known 3d-electron system exhibiting typical heavy fermion behavior. A central question is how such strong mass renormalization emerges in the absence of f-electrons. In this work, we investigate the three-dimensional electronic structure of LiV2O4 thin films using angle-resolved photoemission spectroscopy (ARPES). We identify that… ▽ More LiV2O4 is a spinel-structured compound that stands out as the first known 3d-electron system exhibiting typical heavy fermion behavior. A central question is how such strong mass renormalization emerges in the absence of f-electrons. In this work, we investigate the three-dimensional electronic structure of LiV2O4 thin films using angle-resolved photoemission spectroscopy (ARPES). We identify that an electron-like flat band is derived from a1g orbitals, along with a highly dispersive e'g band strongly coupled with phonons. The overall agreement with dynamical mean-field theory (DMFT) calculations highlights the essential role of inter-orbital Hund's coupling in reducing the a1g bandwidth to 25 meV, approaching a Mott state. Notably, we find that heavy-fermion behavior arises from additional renormalization at the a1g band near the Fermi level, likely driven by many-body interactions at energy scales down to a few meV and potentially linked to geometric frustration inherent to the spinel lattice. These results provide crucial insights into the origin of the heavy fermion behavior in 3d-electron systems. △ Less

Submitted 5 September, 2025; originally announced September 2025.

Journal ref: Chinese Physics Letters 42,100710 (2025)

Quantum Mpemba Effect in Dissipative Spin Chains at Criticality

Authors: Zijun Wei, Mingdi Xu, Xiang-Ping Jiang, Haiping Hu, Lei Pan

Abstract: The Quantum Mpemba Effect (QME) is the quantum counterpart of the classical Mpemba effect--a counterintuitive phenomenon in which a system initially at a higher temperature relax to thermal eauilibrium faster than one at a lower temperature. In this work, we investigate the QME in one-dimensional quantum spin chains coupled to a Markovian environment. By analyzing the full relaxation dynamics gove… ▽ More The Quantum Mpemba Effect (QME) is the quantum counterpart of the classical Mpemba effect--a counterintuitive phenomenon in which a system initially at a higher temperature relax to thermal eauilibrium faster than one at a lower temperature. In this work, we investigate the QME in one-dimensional quantum spin chains coupled to a Markovian environment. By analyzing the full relaxation dynamics governed by the Lindblad master equation, we reveal the emergence of a strong quantum Mpemba effect at quantum critical points. Our findings reveal that criticality enhances the non-monotonic dependence of relaxation times on the initial temperature, leading to anomalously accelerated equilibration. This phenomenon is directly linked to the structure of the Liouvillian spectrum at criticality and the associated overlaps with the initial states. These findings demonstrate that quantum phase transitions could provide a natural setting for realizing and enhancing non-equilibrium phenomena in open quantum systems. △ Less

Submitted 11 September, 2025; v1 submitted 26 August, 2025; originally announced August 2025.

Comments: 9 pages, 6 figures, comments are welcome

Quantum Chaos Diagnostics for non-Hermitian Systems from Bi-Lanczos Krylov Dynamics

Authors: Matteo Baggioli, Kyoung-Bum Huh, Hyun-Sik Jeong, Xuhao Jiang, Keun-Young Kim, Juan F. Pedraza

Abstract: In Hermitian systems, Krylov complexity has emerged as a powerful diagnostic of quantum dynamics, capable of distinguishing chaotic from integrable phases, in agreement with established probes such as spectral statistics and out-of-time-order correlators. By contrast, its role in non-Hermitian settings, relevant for modeling open quantum systems, remains less understood due to the challenges posed… ▽ More In Hermitian systems, Krylov complexity has emerged as a powerful diagnostic of quantum dynamics, capable of distinguishing chaotic from integrable phases, in agreement with established probes such as spectral statistics and out-of-time-order correlators. By contrast, its role in non-Hermitian settings, relevant for modeling open quantum systems, remains less understood due to the challenges posed by complex eigenvalues and the limitations of standard approaches based on orthogonality, such as singular value decomposition. Here we demonstrate that Krylov complexity, computed via the bi-Lanczos algorithm, provides a reliable probe of quantum chaos in non-Hermitian systems, clearly discriminating chaotic and integrable regimes. Our results agree with complex spectral statistics and complex spacing ratios, underscoring the robustness of the method. Universality is supported by extensive tests in both the non-Hermitian Sachdev-Ye-Kitaev model and non-Hermitian random-matrix ensembles across multiple non-Hermitian symmetry classes. △ Less

Submitted 10 February, 2026; v1 submitted 19 August, 2025; originally announced August 2025.

Comments: v2: minor edits, expanded references, and new/improved figures included

Report number: IFT-UAM/CSIC-25-87, APCTP Pre2025 - 018

Resonant dynamics of spin cluster in a periodically driven one-dimensional Rydberg lattice

Authors: Jin-Qiu Xiong, Yu-Hong Yan, Xun-Da Jiang, Yong-Yao Li, Kun-Liang Zhang

Abstract: Rydberg lattice under facilitation conditions can feature kinetic constraints, leading to ballistic and nonergodic behavior at different detuning intensities. Here, we demonstrate that a resonant driving field can achieve effects similar to those under facilitation conditions. We focus on the relaxation dynamics of spin clusters in a periodically driven Rydberg spin lattice. Through an effective H… ▽ More Rydberg lattice under facilitation conditions can feature kinetic constraints, leading to ballistic and nonergodic behavior at different detuning intensities. Here, we demonstrate that a resonant driving field can achieve effects similar to those under facilitation conditions. We focus on the relaxation dynamics of spin clusters in a periodically driven Rydberg spin lattice. Through an effective Hamiltonian for the domain walls of the spin cluster, it is shown that when the driving frequency is resonant with the Rydberg interaction, the spin cluster exhibits ballistic expansion with half the spreading rate compared to the case of facilitation conditions. However, near the resonant point, the spin cluster displays confinement behavior of the Bloch-like oscillations. These results demonstrate the rich dynamic behaviors in the driven Rydberg spin lattices and may find applications in quantum state manipulation. △ Less

Submitted 2 December, 2025; v1 submitted 17 August, 2025; originally announced August 2025.

Comments: 11 pages, 6 figures

Journal ref: Phys. Rev. B 112, 224303 (2025)

Mn4Al11: A Half-Semimetal Candidate with Anomalous Electronic Behaviors

Authors: Shanshan Han, Rongsheng Li, Xingxing Jiang, Ming Lu, Shuxiang Xu, Jiang Zeng, Dong Wu, Nanlin Wang

Abstract: Half-semimetals, characterized by their spin-polarized electronic states, hold significant promise for spintronic applications but remain scarce due to stringent electronic and magnetic criteria. Through a combination of transport measurements and optical spectroscopy, we investigated the intermetallic compound Mn4Al11, which features an exceptionally low carrier concentration and undergoes a magn… ▽ More Half-semimetals, characterized by their spin-polarized electronic states, hold significant promise for spintronic applications but remain scarce due to stringent electronic and magnetic criteria. Through a combination of transport measurements and optical spectroscopy, we investigated the intermetallic compound Mn4Al11, which features an exceptionally low carrier concentration and undergoes a magnetic phase transition near 68 K. Transport measurements reveal anomalies that deviate from typical metallic behavior at low temperatures. Optical spectroscopy indicates a small, nearly frequency-independent optical conductivity in the far-infrared region, with spectral weight decreasing as the temperature drops from 300 K to 50 K. These behaviors suggest a temperaturedependent carrier density and significant scattering of charge carriers. Combining experimental findings with calculated electronic band structures, we propose that Mn4Al11 is a novel half-semimetal candidate exhibiting a ferrimagnetic ground state. △ Less

Submitted 16 August, 2025; originally announced August 2025.

Report number: 2025-0843

Journal ref: Chin. Phys. Lett. 2025

Mixed spin states for robust ferromagnetism in strained SrCoO$_3$ thin films

Authors: Xiquan Zheng, Nicholas B. Brookes, Flora Yakhou-Harris, Yingjie Lyu, Jianbing Zhang, Qian Xiao, Xinyi Jiang, Qingzheng Qiu, Qizhi Li, Shilong Zhang, Xinqiang Cai, Pu Yu, Yi Lu, Yingying Peng

Abstract: Epitaxial strain in transition-metal oxides can induce dramatic changes in electronic and magnetic properties. A recent study on the epitaxially strained SrCoO$_3$ thin films revealed persistent ferromagnetism even across a metal-insulator transition. This challenges the current theoretical predictions, and the nature of the local spin state underlying this robustness remains unresolved. Here, we… ▽ More Epitaxial strain in transition-metal oxides can induce dramatic changes in electronic and magnetic properties. A recent study on the epitaxially strained SrCoO$_3$ thin films revealed persistent ferromagnetism even across a metal-insulator transition. This challenges the current theoretical predictions, and the nature of the local spin state underlying this robustness remains unresolved. Here, we employ high-resolution resonant inelastic x-ray scattering (RIXS) at the Co-$L_3$ edge to probe the spin states of strained SrCoO$_3$ thin films. Compared with CoO$_6$ cluster multiplet calculations, we identify a ground state composed of a mixed high- and low-spin configuration, distinct from the previously proposed intermediate-spin state. Our results demonstrate that the robustness of ferromagnetism arises from the interplay between this mixed spin state and the presence of ligand holes associated with negative charge transfer. These findings provide direct experimental evidence for a nontrivial magnetic ground state in SrCoO$_3$ and offer new pathways for designing robust ferromagnetic systems in correlated oxides. △ Less

Submitted 2 August, 2025; originally announced August 2025.

Comments: 6 pages, 4 figures

Incipient ionic conductors: Ion-constrained lattices achieving superionic-like thermal conductivity by extreme anharmonicity

Authors: Yongheng Li, Chunqiu Lu, Bin Wei, Cong Lu, Xingang Jiang, Daisuke Ishikawa, Taishun Manjo, Caofeng Pan, Alfred Q. R. Baron, Jiawang Hong

Abstract: Phonon liquid-like thermal conduction in the solid state enables superionic conductors to serve as efficient thermoelectric device candidates. While liquid-like motion of ions effectively suppresses thermal conductivity (κ), their high mobility concurrently triggers material degradation due to undesirable ion migration and consequent metal deposition, making it still a challenge to balancing low κ… ▽ More Phonon liquid-like thermal conduction in the solid state enables superionic conductors to serve as efficient thermoelectric device candidates. While liquid-like motion of ions effectively suppresses thermal conductivity (κ), their high mobility concurrently triggers material degradation due to undesirable ion migration and consequent metal deposition, making it still a challenge to balancing low κand high stability. Here, we report a superionic-like thermal transport alongside restricted long-range ion migration in CsCu_2I_3 with incipient ionic conduction, using synchrotron X-ray diffraction, inelastic X-ray scattering, and machine-learning potential-based simulations. We reveal that the Cu ions exhibit confined migration between CuI_4 tetrahedra at high temperatures, displaying extreme anharmonicity of dominated phonons beyond conventional rattling and comparable to that in superionic conductorsl. Consequently, a glass-like κ(~0.3 W m^{-1} K^{-1} at 300 K) following the relationship of κ~ T^{0.17}, was achieved along the x-direction, where Cu ion migration is three oders of magnitude lower than in superionic conductors. These results highlight the advantage of incipient ionic conductors in simultaneously maintaining both low κand high stability, elucidate the thermal transport mechanism via ion migration constraints, and pave an effective pathway toward ultralow thermal conductivity in ionic conductors. △ Less

Submitted 15 September, 2025; v1 submitted 4 July, 2025; originally announced July 2025.

Comments: 24 pages, 5 figures

Complexity of PXP scars revisited

Authors: Pawel Caputa, Xuhao Jiang, Sinong Liu

Abstract: We revisit a quantum quench scenario in which either a scarring or thermalizing initial state evolves under the PXP Hamiltonian. Within this framework, we study the time evolution of spread complexity and related quantities in the Krylov basis. We find that the Lanczos coefficients $b_n$, as functions of the iteration number $n$, exhibit a characteristic arched growth and decay, followed by errati… ▽ More We revisit a quantum quench scenario in which either a scarring or thermalizing initial state evolves under the PXP Hamiltonian. Within this framework, we study the time evolution of spread complexity and related quantities in the Krylov basis. We find that the Lanczos coefficients $b_n$, as functions of the iteration number $n$, exhibit a characteristic arched growth and decay, followed by erratic oscillations which we refer to as buttress. The arched profile predominantly arises from contributions within the quantum many-body scar subspace, while the buttress is linked to thermalization dynamics. To explain this behavior, we utilize the representation theory of $\mathfrak{s}l_3(\mathbb{C})$, allowing us to decompose the PXP Hamiltonian into a linear component and a residual part. The linear term governs the formation and width of the arch, and we observe that that there exists a threshold of arch width which determines whether a given initial state exhibits scarring. Meanwhile, the residual term accounts qualitatively for the emergence of the buttress. We estimate an upper bound for the extent of the buttress using Lucas numbers. Finally, we demonstrate that spread complexity oscillates periodically over time for scarred initial states, whereas such oscillations are suppressed in thermalizing cases. △ Less

Submitted 26 June, 2025; originally announced June 2025.

Comments: 82 pages, 19 figures

Report number: YITP-25-94

Collision-assisted information scrambling on a configurable photonic chip

Authors: Xiao-Wen Shang, Shu-Yi Liang, Guan-Ju Yan, Xin-Yang Jiang, Zi-Ming Yin, Hao Tang, Jian-Peng Dou, Ze-Kun Jiang, Yu-Quan Peng, Xian-Min Jin

Abstract: Quantum interference and entanglement are in the core of quantum computations. The fast spread of information in the quantum circuit helps to mitigate the circuit depth. Although the information scrambling in the closed systems has been proposed and tested in the digital circuits, how to measure the evolution of quantum correlations between systems and environments remains a delicate and open ques… ▽ More Quantum interference and entanglement are in the core of quantum computations. The fast spread of information in the quantum circuit helps to mitigate the circuit depth. Although the information scrambling in the closed systems has been proposed and tested in the digital circuits, how to measure the evolution of quantum correlations between systems and environments remains a delicate and open question. Here, we propose a photonic circuit to investigate the information scrambling in an open quantum system by implementing the collision model with cascaded Mach-Zehnder interferometers. We numerically simulate the photon propagation and find that the tripartite mutual information strongly depends on the system-environment and environment-environment interactions. We further reduce the number of observables and the number of shots required to reconstruct the density matrix by designing an enhanced compressed sensing. Our results provide a reconfigurable photonic platform for simulating open quantum systems and pave the way for exploring controllable dissipation and non-Markovianity in discrete-variable photonic computing. △ Less

Submitted 19 June, 2025; originally announced June 2025.

Comments: 7 pages, 4 figures. Comments are welcome!

Low and Anisotropic Thermal Conductivity in Mixed-Valent Sn$_2$S$_3$

Authors: Xingang Jiang, Yongheng Li, Weiping Guo, Qi Ren, Gang Tang, Zhong-Zhen Luo, Jiawang Hong

Abstract: Compounds of Sn, such as SnSe and SnS, exhibit novel phonon characteristics and low thermal conductivity, making them emerging star materials in the thermoelectric family. In this work, through the Boltzmann transport equation scheme and the Wigner thermal transport model, quasi-1D mixed-valent Sn$_2$S$_3$ were found to exhibit a low thermal conductivity along c-axis with a weak temperature depend… ▽ More Compounds of Sn, such as SnSe and SnS, exhibit novel phonon characteristics and low thermal conductivity, making them emerging star materials in the thermoelectric family. In this work, through the Boltzmann transport equation scheme and the Wigner thermal transport model, quasi-1D mixed-valent Sn$_2$S$_3$ were found to exhibit a low thermal conductivity along c-axis with a weak temperature dependence. The low thermal conductivity is attributed to the anharmonic rattling vibrations of weakly bonded Sn(II) atoms, which are influenced by the coulomb interaction of lone pairs at adjacent Sn(II) atoms. The rattling of Sn(II) induces low-frequency flat optical phonons and avoids crossing behavior. The atomic displacements and mean square displacement (MSD) analysis reveal that Sn(II) atoms exhibit significantly greater and anisotropic displacements compared to Sn(IV) and S, confirming that Sn(II) behaves as a rattler. The results obtained from this work suggest an opportunity to discover low thermal conductivity in mixed-valent compounds. △ Less

Submitted 11 June, 2025; originally announced June 2025.

Journal ref: Phys. Rev. B 112, 144304 (2025)

Ultrafast Orbital-Selective Photodoping Melts Charge Order in Overdoped Bi-based Cuprates

Authors: Xinyi Jiang, Qizhi Li, Qingzheng Qiu, Li Yue, Junhan Huang, Yiwen Chen, Byungjune Lee, Hyeongi Choi, Xingjiang Zhou, Tao Dong, Nanlin Wang, Hoyoung Jang, Yingying Peng

Abstract: High-temperature superconductivity in cuprates remains one of the enduring puzzles of condensed matter physics, with charge order (CO) playing a central yet elusive role, particularly in the overdoped regime. Here, we employ time-resolved X-ray absorption spectroscopy and resonant X-ray scattering at a free-electron laser to probe the transient electronic density of states and ultrafast CO dynamic… ▽ More High-temperature superconductivity in cuprates remains one of the enduring puzzles of condensed matter physics, with charge order (CO) playing a central yet elusive role, particularly in the overdoped regime. Here, we employ time-resolved X-ray absorption spectroscopy and resonant X-ray scattering at a free-electron laser to probe the transient electronic density of states and ultrafast CO dynamics in overdoped (Bi,Pb)$_{2.12}$Sr$_{1.88}$CuO$_{6+δ}$. We reveal a striking pump laser wavelength dependence - the 800 nm light fails to suppress CO, whereas the 400 nm light effectively melts it. This behavior originates from the fact that 400 nm photons can promote electrons from the Zhang-Rice singlet band to the upper Hubbard band or apical oxygen states, while 800 nm photons lack the energy to excite electrons across the charge-transfer gap. The CO recovery time ($\sim$3 ps) matches that of the underdoped cuprates, indicating universal electronic instability in the phase diagram. Additionally, melting overdoped CO requires an order-of-magnitude higher fluence highlighting the role of lattice interactions. Our findings demonstrate orbital-selective photodoping and provide a route to ultrafast control of emergent quantum phases in correlated materials. △ Less

Submitted 5 June, 2025; originally announced June 2025.

Comments: 13 pages, 11 figures, comments are welcome

Spatial Offset of Excited States in Non-Hermitian Lattices

Authors: Xiaohan Jiang, Yuanyuan Pan, Yang Zhang, Ye Xiong

Abstract: We investigate the behavior of light-wave packets injected into non-Hermitian microcavity lattices under highly dissipative conditions. While all eigenstates of the lattice exhibit exponential decay, a specifically excited state maintains coherent propagation. In a one-dimensional lattice, this state undergoes a spatial displacement shift away from the injection position, which is a fu… ▽ More We investigate the behavior of light-wave packets injected into non-Hermitian microcavity lattices under highly dissipative conditions. While all eigenstates of the lattice exhibit exponential decay, a specifically excited state maintains coherent propagation. In a one-dimensional lattice, this state undergoes a spatial displacement shift away from the injection position, which is a fundamental property of non-Hermitian systems with a point gap when the spectrum encircles a finite region in the complex plane. Extending such a shift to two-dimensional lattices reveals a geometrically anomalous V-shaped wave packet formation with orientation-tunable arms. Notably, this geometric control mechanism enables all-optical steering of non-Hermitian photonic states without requiring structural modifications. △ Less

Submitted 14 May, 2025; originally announced May 2025.

Comments: 5 pages, 6 figures

Expedited thermalization dynamics in incommensurate systems

Authors: Mingdi Xu, Zijun Wei, Xiang-Ping Jiang, Lei Pan

Abstract: We study the thermalization dynamics of a quantum system embedded in an incommensurate potential and coupled to a Markovian thermal reservoir. The dephasing induced by the bath drives the system toward an infinite-temperature steady state, erasing all initial information-including signatures of localization. We find that initially localized states can relax to the homogeneous steady state faster t… ▽ More We study the thermalization dynamics of a quantum system embedded in an incommensurate potential and coupled to a Markovian thermal reservoir. The dephasing induced by the bath drives the system toward an infinite-temperature steady state, erasing all initial information-including signatures of localization. We find that initially localized states can relax to the homogeneous steady state faster than delocalized states. Moreover, low-temperature initial states thermalize to infinite temperature more rapidly than high-temperature states -- a phenomenon reminiscent of the Mpemba effect, in which hotter liquids freeze faster than colder ones. The slowest relaxation mode in the Liouvillian spectrum plays a critical role in the expedited thermalization for localized or cold initial states. Our results reveal that the combination of disordered structure and environmental dissipation may lead to non-trivial thermalization behavior, which advances both the conceptual framework of the Mpemba effect and the theoretical understanding of nonequilibrium processes in dissipative disordered systems. △ Less

Submitted 25 May, 2025; v1 submitted 6 May, 2025; originally announced May 2025.

Comments: 8 pages, 4 figures, comments are welcome

Journal ref: Phys. Rev. A 112, 042210 (2025)

Anomalous valley Hall effect in monolayer chromium-based triple-Q magnets

Authors: Xiu-Cai Jiang, Li-Ya Qiao, Yu-Zhong Zhang

Abstract: Using the density functional theory calculations, we predict that several monolayer chromium-based materials exhibit a triple-Q tetrahedral magnetic insulating ground state. By studying the effect of biaxial strain on monolayer CrSi$\rm{_2}$P$\rm{_4}$ under various on-site Coulomb interactions, we reveal that this magnetic insulating state, sandwiched between the itinerant $120^{\circ}$ coplanar n… ▽ More Using the density functional theory calculations, we predict that several monolayer chromium-based materials exhibit a triple-Q tetrahedral magnetic insulating ground state. By studying the effect of biaxial strain on monolayer CrSi$\rm{_2}$P$\rm{_4}$ under various on-site Coulomb interactions, we reveal that this magnetic insulating state, sandwiched between the itinerant $120^{\circ}$ coplanar noncollinear antiferromagnetic and ferromagnetic states, originates from the competition between antiferromagnetic exchange and double exchange interactions of Cr 3$d$ electrons which can also be applied to account for the ground states in other chromium-based materials. Remarkably, anomalous valley Hall effect with giant valley splitting is discovered in the magnetic states of these inversion-asymmetric systems without requiring spin-orbit coupling or net magnetization. Our findings open a new avenue towards exploring monolayer materials for valleytronics. △ Less

Submitted 5 May, 2025; originally announced May 2025.

Comments: 8 pages, 4 figures

Journal ref: Phys. Rev. B 111, L140416 (2025)

Design Optimization of Flip FET Standard Cells with Dual-sided Pins for Ultimate Scaling

Authors: Rui Gui, Haoran Lu, Jiacheng Sun, Xun Jiang, Lining Zhang, Ming Li, Yibo Lin, Runsheng Wang, Heng Wu, Ru Huang

Abstract: Recently, we proposed a novel transistor architecture for 3D stacked FETs called Flip FET (FFET), featuring N/P transistors back-to-back stacked and dual-sided interconnects. With dual-sided power rails and signal tracks, FFET can achieve an aggressive 2.5T cell height. As a tradeoff, the complex structure and limited numbers of M0 tracks could limit the standard cell design. As a solution, multip… ▽ More Recently, we proposed a novel transistor architecture for 3D stacked FETs called Flip FET (FFET), featuring N/P transistors back-to-back stacked and dual-sided interconnects. With dual-sided power rails and signal tracks, FFET can achieve an aggressive 2.5T cell height. As a tradeoff, the complex structure and limited numbers of M0 tracks could limit the standard cell design. As a solution, multiple innovations were introduced and examined in this work. Based on an advanced node design rule, several unique building blocks in FFET such as drain merge (DM), gate merge (GM), field drain merge (FDM) and buried signal track (BST) were investigated. Other key design concepts of multi-row, split gate and dummy gate insertion (DG) were also carefully studied, delivering around 35.6% area reduction compared with 3T CFET. Furthermore, the symmetric design of FFET has unique superiority over CFET thanks to the separate N/P logic on two sides of the wafer and their connections using DM and GM. New routing scheme with dual-sided output pins on both wafer frontside (FS) and backside (BS) was proposed for the first time. Finally, we conducted a comprehensive evaluation on complex cell design, taking AOI22 as an example. New strategies were proposed and examined. The FDM design is identified as the best, outperforming the BST and dummy gate design by 1.93% and 5.13% for the transition delay. △ Less

Submitted 14 April, 2025; originally announced April 2025.

Comments: Accepted by IEEE Transactions on Electron Devices

Dissipation induced localization-delocalization transition in a flat band

Authors: Mingdi Xu, Zijun Wei, Xiang-Ping Jiang, Lei Pan

Abstract: The interplay between dissipation and localization in quantum systems has garnered significant attention due to its potential to manipulate transport properties and induce phase transitions. In this work, we explore the dissipation-induced extended-localized transition in a flat band model, where the system's asymptotic state can be controlled by tailored dissipative operators. By analyzing the st… ▽ More The interplay between dissipation and localization in quantum systems has garnered significant attention due to its potential to manipulate transport properties and induce phase transitions. In this work, we explore the dissipation-induced extended-localized transition in a flat band model, where the system's asymptotic state can be controlled by tailored dissipative operators. By analyzing the steady-state density matrix and dissipative dynamics, we demonstrate that dissipation is able to drive the system to states dominated by either extended or localized modes, irrespective of the initial conditions. The control mechanism relies on the phase properties of the dissipative operators, which selectively favor specific eigenstates of the Hamiltonian. Our findings reveal that dissipation can be harnessed to induce transitions between extended and localized phases, offering a novel approach to manipulate quantum transport in flat band systems. This work not only deepens our understanding of dissipation-induced phenomena in flat band systems but also provides a new avenue for controlling quantum states in open systems. △ Less

Submitted 13 April, 2025; originally announced April 2025.

Comments: 10 pages, 9 figures, comments are welcome

Singular Value Decomposition and Its Blind Spot for Quantum Chaos in Non-Hermitian Sachdev-Ye-Kitaev Models

Authors: Matteo Baggioli, Kyoung-Bum Huh, Hyun-Sik Jeong, Xuhao Jiang, Keun-Young Kim, Juan F. Pedraza

Abstract: The study of chaos and complexity in non-Hermitian quantum systems poses significant challenges due to the emergence of complex eigenvalues in their spectra. Recently, the singular value decomposition (SVD) method was proposed to address these challenges. In this work, we identify two critical shortcomings of the SVD approach when analyzing Krylov complexity and spectral statistics in non-Hermitia… ▽ More The study of chaos and complexity in non-Hermitian quantum systems poses significant challenges due to the emergence of complex eigenvalues in their spectra. Recently, the singular value decomposition (SVD) method was proposed to address these challenges. In this work, we identify two critical shortcomings of the SVD approach when analyzing Krylov complexity and spectral statistics in non-Hermitian settings. First, we show that SVD fails to reproduce conventional eigenvalue statistics in the Hermitian limit for systems with non-positive definite spectra, as exemplified by a variant of the Sachdev-Ye-Kitaev (SYK) model. Second, and more fundamentally, Krylov complexity and spectral statistics derived via SVD cannot distinguish chaotic from integrable non-Hermitian dynamics, leading to results that conflict with complex spacing ratio analysis. Our findings reveal that SVD is inadequate for probing quantum chaos in non-Hermitian systems, and we advocate employing more robust methods, such as the bi-Lanczos algorithm, for future research in this direction. △ Less

Submitted 21 May, 2025; v1 submitted 14 March, 2025; originally announced March 2025.

Comments: v1: 6 pages, 5 figures, v2: references added, minor changes, v3: matching the published version

Report number: IFT-UAM/CSIC-25-23

Journal ref: Phys. Rev. D 111, L101904, Published 21 May, 2025

Multistate Control of Nonlinear Photocurrents in Optoferroelectrics via phase manipulation of light field

Authors: Ali Kazempour, Esmaeil Taghizadeh Sisakht, Mahmut Sait Okyay, Xiao Jiang, Shunsuke Sato, Noejung Park

Abstract: Ultrafast optical control of ferroelectricity based on short and intense light can be utilized to achieve accurate manipulations of ferroelectric materials, which may pave a basis for future breakthrough in nonvolatile memories. Here, we demonstrate that phase manipulation of electric field in the strong field sub-cycle regime induces a nonlinear injection current, efficiently coupling with the to… ▽ More Ultrafast optical control of ferroelectricity based on short and intense light can be utilized to achieve accurate manipulations of ferroelectric materials, which may pave a basis for future breakthrough in nonvolatile memories. Here, we demonstrate that phase manipulation of electric field in the strong field sub-cycle regime induces a nonlinear injection current, efficiently coupling with the topology of band structure and enabling dynamic reversal of both current and polarization. Our time-dependent first-principles calculations reveal that tuning the phase of linearly or circularly polarized light through time-varying chirp, or constant carrier envelop phases within sub-laser-cycle dynamics effectively breaks the time-reversal symmetry, allowing the control over current and electronic polarization reversal over multi-ferroelectric states. Our time- and momentum-resolved transverse current analysis reveal the significance of Berry curvature higher order poles in the apparent association between the odd (even) orders of Berry curvature multipoles to odd (even) pseudo-harmonics in driving polarization dynamics reversal. We suggest that these phase manipulations of short pulse waveform may lead to unprecedented accurate control of nonlinear photocurrents and polarization states, which facilitate the development of precise ultrafast opto-ferroelectric devices. △ Less

Submitted 22 February, 2025; originally announced February 2025.

Coherent detection of the oscillating acoustoelectric effect in graphene

Authors: Yicheng Mou, Jiayu Wang, Haonan Chen, Yingchao Xia, Hailong Li, Qing Yan, Xue Jiang, Yijia Wu, Wu Shi, Hua Jiang, X. C. Xie, Cheng Zhang

Abstract: In recent years, surface acoustic waves (SAWs) have emerged as a novel technique for generating quasiparticle transport and band modulation in condensed matter systems. SAWs interact with adjacent materials through piezoelectric and strain fields, dragging carriers in the direction of wave propagation. Most studies on the acoustoelectric effect have focused on the collective directional motion of… ▽ More In recent years, surface acoustic waves (SAWs) have emerged as a novel technique for generating quasiparticle transport and band modulation in condensed matter systems. SAWs interact with adjacent materials through piezoelectric and strain fields, dragging carriers in the direction of wave propagation. Most studies on the acoustoelectric effect have focused on the collective directional motion of carriers, which generates a steady electric potential difference, while the oscillating component from dynamic spatial charge modulation has remained challenging to probe. In this work, we report the coherent detection of oscillating acoustoelectric effect in graphene. This is achieved through the coherent rectification of spatial-temporal charge oscillation with electromagnetic waves emitted by interdigital transducers. We systematically investigate the frequency and gate dependence of rectified signals and quantitatively probe the carrier redistribution dynamics driven by SAWs. The observation of oscillating acoustoelectric effect provides direct access to the dynamic spatial charge modulation induced by SAWs through transport experiments. △ Less

Submitted 13 February, 2025; originally announced February 2025.

Comments: 12 pages, 4 figures, to appear in PRL

Journal ref: Phys. Rev. Lett. 134, 096301 (2025)