近日，华中科技大学和武汉量子技术研究所的吕新友及其研究团队取得一项新进展。经过不懈努力，他们对非厄米拓扑相中的周期性非互易传输和纠缠进行研究。相关研究成果已于2024年7月18日在国际知名学术期刊《物理评论A》上发表。

该研究团队通过研究一维非厄米微环形空腔阵列的拓扑性质和非互易性，发现非厄米拓扑相变周期性发生，当空腔阵列处于拓扑非平凡相位时，周期性边缘空腔非互易性出现并在单腔异常点(EPs)处达到峰值。这种非互易性与拓扑保护的手性模式激发有关。它在经典和量子非互易器件中都有实际应用，如光隔离器和非互易光力学纠缠器件。

这些非互易性是拓扑保护的，因此对系统参数的无序具有鲁棒性。这项研究工作为产生具有非厄米拓扑效应的周期性单腔非互易提供了一种替代方法，并从根本上推动了拓扑物理和非互易光学领域的发展。

据悉，非互易器件是光信息处理和手性量子网络的重要组成部分。

附：英文原文

Title: Periodically nonreciprocal transmission and entanglement in a non-Hermitian topological phase

Author: Zi-Hao Li, Li-Li Zheng, Gui-Lei Zhu, Ying Wu, Xin-You Lü

Issue&Volume: 2024/07/18

Abstract: Nonreciprocal devices are crucial components in optical information processing and chiral quantum networks. By investigating the topological property and the nonreciprocity in a one-dimensional, non-Hermitian microtoroid cavities array, we find that non-Hermitian topological phase transition periodically occurs, and the associated periodic edge-cavity nonreciprocity emerges and peaks at the single-cavity exceptional points (EPs) when the array of cavities is in the topologically nontrivial phase. This nonreciprocity is associated with the topologically protected chiral-mode excitation. It has practical applications in both classical and quantum nonreciprocal devices, such as optical isolators and nonreciprocal optomechanical entanglement devices. These nonreciprocities are topologically protected, thus are robust to the disorder of system parameters. Our work offers an alternative approach to generate periodic single-cavity nonreciprocity with non-Hermitian topological effect, and fundamentally advance the fields of topological physics and nonreciprocity optics.

DOI: 10.1103/PhysRevA.110.013515

Source: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.110.013515