Abstract
AbstractIt has been known that the bulk-boundary correspondence (BBC) of the non-Hermitian skin effect is characterized by the topology of the complex eigenvalue spectra, while the topology of the wave function gives rise to Hermitian BBC with conventional boundary modes. In this work, we go beyond the known description of the non-Hermitian topological phase and find a different type of BBC that appears in generalized boundary conditions. The generalized Brillouin zone (GBZ) possesses non-trivial topological structures in the intermediate boundary condition between open and periodic boundary conditions. Unlike the conventional BBC, the topological phase transition is characterized by the generalized momentum touching of GBZ, which manifests as exceptional points. As a realization of our proposal, we suggest the non-reciprocal Kuramoto oscillator lattice, where phase slips accompany exceptional points as a signature of such topological phase transition. Our work establishes an understanding of non-Hermitian topological matter by complementing the non-Hermitian BBC as a general foundation of the non-Hermitian topological systems.
Publisher
Springer Science and Business Media LLC
Subject
General Physics and Astronomy
Reference26 articles.
1. Ashida, Y., Gong, Z. & Ueda, M. Non-hermitian physics. Adv. Phys. 69, 249–435 (2020).
2. Torres, LuisE. F. Foa Perspective on topological states of non-hermitian lattices. J. Phys.: Mater. 3, 014002 (2019).
3. Okuma, N. & Sato, M. Non-hermitian topological phenomena: a review. Annu. Rev. Condens. Matter Phys. 14, 83–107 (2023).
4. Zhang, X., Zhang, T., Lu, Ming-Hui & Chen, Yan-Feng A review on non-hermitian skin effect. Adv. Phys.: X 7, 2109431 (2022).
5. Martinez Alvarez, V. M., Barrios Vargas, J. E. & Foa Torres, L. E. F. Non-hermitian robust edge states in one dimension: anomalous localization and eigenspace condensation at exceptional points. Phys. Rev. B 97, 121401 (2018).