近日，华南师范大学张丹伟团队研究了非厄米非阿贝尔拟周期晶格中的迁移率环。相关论文于2025年7月29日发表在《物理评论A》杂志上。

研究组分析了带有SU(2)非阿贝尔人工规范场的自旋1/2非互易Aubry-André链中的局域化和拓扑性质。结果表明，与阿贝尔情况不同，非阿贝尔情况下会出现迁移率环，并伴随非厄米拓扑相变。作为迁移率边缘的非厄米扩展，在周期性边界条件下，这些迁移率环会在复能平面上将安德森局域化本征态与扩展本征态区分开来。

基于拓扑性质，研究组得到了迁移率环的精确表达式。此外，他们还对相应的指标（如逆参与率、归一化参与比、缠绕数、非厄米谱结构和波函数）进行了数值研究。数值结果与分析表达式高度一致，证实了迁移率环的出现。

附：英文原文

Title: Mobility rings in a non-Hermitian non-Abelian quasiperiodic lattice

Author: Rui-Jie Chen, Guo-Qing Zhang, Zhi Li, Dan-Wei Zhang

Issue&Volume: 2025/07/29

Abstract: We study localization and topological properties in spin-1/2 nonreciprocal Aubry-André chain with SU(2) non-Abelian artificial gauge fields. The results reveal that, different from the Abelian case, mobility rings will emerge in the non-Abelian case accompanied by the non-Hermitian topological phase transition. As the non-Hermitian extension of mobility edges, such mobility rings separate Anderson-localized eigenstates from extended eigenstates in the complex energy plane under the periodic boundary condition. Based on the topological properties, we obtain the exact expression of the mobility rings. Furthermore, the corresponding indicators such as inverse participation rate, normalized participation ratio, winding number, non-Hermitian spectral structures, and wave functions are numerically studied. The numerical results are in good agreement with the analytical expression, which confirms the emergence of mobility rings.

DOI: 10.1103/zfrn-53lz

Source: https://journals.aps.org/pra/abstract/10.1103/zfrn-53lz