Han Yanzhen, Liu Jianxiao, Chong Shiyao, Du Jingjing, Meng Linghui, Gao Yingjie
College Electronics Information Engineering, Hengshui University, Hengshui 053000, China.
School of Electronics and Information Engineering, Jinling Institute of Technology, Nanjing 211169, China.
Materials (Basel). 2025 Mar 23;18(7):1417. doi: 10.3390/ma18071417.
Revealing singular quantum phenomena in various non-Hermitian systems is a hot topic in condensed matter physics research, with the bulk-boundary correspondence being one of the core issues in non-Hermitian topological states. In addition, the spin-orbit coupling (SOC) applied to electrons moving in the electric field in the material can bring unique topological properties to the energy band of the material. We investigated the topological phase transition of a non-Hermitian Su-Schrieffer-Heeger (SSH) model with SOC in the generalized Brillouin zone (GBZ). We demonstrate that SOC can alter the position and number of phase transition points. Due to the non-Hermitian skin effect, the bulk-boundary correspondence is broken, and the local positions of zero mode and bulk eigenstates will also change. By unitary transformation, two subspaces were obtained, and the exact solution of topological phase transition was obtained in the GBZ. The exact solution of non-Hermitian systems with the Dresselhaus and Rashba types of SOC is consistent with the numerical solutions. This result can be applied to more complex non-Hermitian models, providing a strong reference for experimental researchers in topological materials.
在各种非厄米系统中揭示奇异量子现象是凝聚态物理研究中的一个热门话题,其中体边对应是非厄米拓扑态的核心问题之一。此外,应用于材料中在电场中运动的电子的自旋轨道耦合(SOC)可以给材料的能带带来独特的拓扑性质。我们研究了广义布里渊区(GBZ)中具有SOC的非厄米Su-Schrieffer-Heeger(SSH)模型的拓扑相变。我们证明了SOC可以改变相变点的位置和数量。由于非厄米趋肤效应,体边对应被打破,零模和体本征态的局部位置也会发生变化。通过幺正变换,得到了两个子空间,并在GBZ中得到了拓扑相变的精确解。具有Dresselhaus和Rashba型SOC的非厄米系统的精确解与数值解一致。这一结果可应用于更复杂的非厄米模型,为拓扑材料的实验研究人员提供有力参考。