近日，扬州大学的何爱垒及其研究团队取得一项新进展。经过不懈努力，他们揭示了具有虚势和非互易跳跃的二聚晶格中的非厄米拓扑激发传输过程。相关研究成果已于2024年3月25日在国际知名学术期刊《物理评论A》上发表。

该研究团队针对一维Su-Schrieffer-Heeger晶格，深入探索了基于纯虚位势和非互易最近邻跳跃的激励拓扑边缘传输机制。他们的研究发现，当系统仅包含非互易晶格内跳跃时，拓扑激发传输的实现需满足一个特定条件：非厄米集肤效应的局域化方向必须与边缘态的局域化方向相匹配。而当晶格同时拥有纯虚场电势和非互易晶格内跳跃时，研究人员进一步证实，相较于非厄米集肤效应，正纯虚电势在实现拓扑激发传输中起到了更为关键的主导作用。

此外，他们还深入探讨了纯虚场电势与非互易晶格间跳跃之间的协同作用，发现大非互易参数所引发的非厄米趋肤效应在拓扑激励传输中起着决定性的作用。这一研究揭示了两种非厄米效应对拓扑激发传输的差异化影响，这可能会促进拓扑传输在实际开放量子系统中的实现。

附：英文原文

Title: Non-Hermitian topological excitation transmission in the dimerized lattice with imaginary potential and nonreciprocal hopping

Author: Lu Qi, Qiao-Nan Li, Ning Han, Mingzhu Li, Xiu-Yun Zhang, Ai-Lei He

Issue&Volume: 2024/03/25

Abstract: We investigate the topological edge transmission of excitation based on the one-dimensional Su-Schrieffer-Heeger lattice with purely imaginary on-site potential and nonreciprocal nearest-neighbor hopping. We find that, when the system has only the nonreciprocal intracell hopping, the topological excitation transmission can be implemented only when the localization direction of the non-Hermitian skin effect matches the localization direction of edge state. When the lattice has the purely imaginary on-site potential and nonreciprocal intracell hopping, we demonstrate that the positive purely imaginary potential is the dominant effect of implementing the topological excitation transmission compared with the non-Hermitian skin effect. Furthermore, we also investigate the joint effect between the purely imaginary on-site potential and nonreciprocal intercell hopping, which reveals that the non-Hermitian skin effect induced via the large nonreciprocal parameter determines the successful topological excitation transmission. Our investigations show the different influences of two kinds of non-Hermitian effects on the topological excitation transmission, which may promote the implementation of topological transmission in the practical open quantum system.

DOI: 10.1103/PhysRevA.109.032428

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.109.032428