Topological braiding and dynamic probing of phase transitions across temporal interfaces in non-Hermitian systems
Phys. Rev. B 113, 134312 – Published 27 April, 2026
DOI: https://doi.org/10.1103/c48h-w16h
Abstract
Non-Hermitian systems give rise to distinct topological phenomena, yet their manifestations at temporal interfaces characterized by abrupt changes in system parameters remain largely unexplored. Upon an abrupt alteration of the Hamiltonian in a one-dimensional non-Hermitian system, the ensuing temporal interface excites both reflected and refracted wave modes. By introducing a sublattice-symmetric Hamiltonian, this study reveals the topological effects at such temporal interfaces. We find that the reflection and refraction coefficients exhibit a topological braiding structure. This structure is directly determined by the difference in the topological invariants across the interface, establishing a bulk-edge correspondence for temporal interfaces in non-Hermitian systems. Furthermore, we propose a dynamical probe that leverages the eigenvector overlap at the temporal interface to detect topological phase transitions. These findings establish a fundamental connection between topological braiding and nonreciprocal dynamics at temporal interfaces, providing a method to explore phase transition detection and nonreciprocal phenomena in time-varying non-Hermitian systems.
