Non-Hermitian bulk-boundary correspondence via scattering theory

Haoshu Li; Qian Niu

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arXiv · 2302.07148

Non-Hermitian bulk-boundary correspondence via scattering theory

Haoshu Li·Qian Niu

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Abstract

The conventional bulk-boundary correspondence breaks down in non-Hermitian systems. In this paper, we reestablish the bulk-boundary correspondence in one-dimensional non-Hermitian systems by applying the scattering theory, which is a systematical way in various symmetry classes. Based on the scattering theory, it is discovered that the topological invariant can be obtained by solving a generalized eigenproblem without calculating the generalized Brillouin zone. As a direct consequence, we unveil a new type of topological phase transition without typical bulk enengy gap closing and an unstable phase with topological boundary states, dubbed the critical topological phase.

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Haoshu Li, Qian Niu. 2023-02-14. Non-Hermitian bulk-boundary correspondence via scattering theory. https://arxiv.org/abs/2302.07148

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