相互作用准周期自旋链中的多体迁移率边与非厄米皮肤效应
Many-Body Mobility Edge and Non-Hermitian Skin Effect in an Interacting Quasi-Periodic Spin Chain
浏览论文内容
中文总结 AI 辅助
本研究探究受准周期纵向场的相互作用非厄米自旋链，发现“D形”多体迁移率边，揭示其与多体皮肤效应的关联，绘制统一相图并明确其在开放量子多体系统物理中的关键作用。
中文摘要 AI 辅助
非厄米多体物理揭示了拓扑、局域化与边界效应之间丰富的相互作用，然而这些效应在相互作用无序系统中的集体行为仍未得到充分探索。本研究中，我们探究了一个受准周期纵向场作用的相互作用非厄米自旋链，该系统提供了一个统一且可控的环境，其中非厄米动力学、相互作用与局域化机制相互交织。值得注意的是，我们发现了一种“D形”多体迁移率边，它分隔了扩展态与局域化本征态，同时界定了多体局域化和多体皮肤效应的区域；多体皮肤效应指在开放边界条件下，多体本征态因相互作用、非厄米性与驱动振幅的共同作用而出现向边界的异常漂移。我们证明，皮肤效应会在非厄米本征态中引发多分形标度，为多体皮肤效应提供了明确特征。利用分形维数、复本征值分数与多体逆参与率等诊断工具，我们绘制了统一相图，所有测量指标均一致识别出“D形”迁移率边。最后，我们通过复能级间距统计与密度不平衡、纠缠增长、波包演化等动力学可观测量探究这种相互作用，最终得到了涵盖多体皮肤效应与局域化相变的丰富多体迁移率相图。我们的结果明确了“D形”多体迁移率边的决定性特征，并强调其在塑造开放量子多体系统物理性质中的关键作用。
英文摘要
Non-Hermitian many-body physics reveals a rich interplay between topology, localization, and boundary effects, yet their collective behavior in interacting disordered systems remains largely unexplored. In this work, we study an interacting non-Hermitian spin chain subject to a quasi-periodic longitudinal field, providing a unified and controlled setting, where non-Hermitian dynamics, interactions, and localization mechanisms intertwine. Remarkably, we discover a "D-shaped" many-body mobility edge that separates extended and localized eigenstates, while simultaneously delineating regimes of many-body localization and the many-body skin effect (where many-body eigenstates acquire an anomalous drift towards a boundary under open boundaries) emerging from the combined action of interactions, non-Hermiticity, and driving amplitude. We demonstrate that the skin effect induces multifractal scaling in the non-Hermitian eigenstates, providing a clear signature of the many-body skin effect. Employing diagnostics such as the fractal dimension, complex eigenvalue fractions, and many-body inverse participation ratios, we map out a unified phase diagram in which all measures consistently identify the "D-shaped" mobility edge. Finally, we probe this interplay using both complex level-spacing statistics and dynamical observables such as density imbalance, entanglement growth, and wave-packet evolution, culminating in a rich many-body mobility phase diagram that captures both the many-body skin effect and localization transitions. Our results identify a clear, defining signature of the "D-shaped" many-body mobility edge, and underscore its pivotal role in shaping the physics of open quantum many-body systems.
