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arXiv · 2403.18268

Non-Hermitian Topology and Boundary Jordan Chains with Generalized Chiral Symmetry

Alex Westström·Wenbu Duan·Jian Li
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Abstract

We study a generalization of chiral symmetry applicable to non-Hermitian systems and its topological consequences on one-dimensional chains. We find a rich family of topological phases characterized not by a single winding number, but a vector of them. More importantly, we uncover a novel type of bulk-boundary correspondence, where the vector of winding numbers in the bulk corresponds to the set of Jordan chains of various length at the boundary. This in turn leads to highly unconventional chiral-charge distributions on both edges. Our work extends the topological classification of the non-Hermitian AIII class along a new axis.

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Alex Westström, Wenbu Duan, Jian Li. 2024-03-27. Non-Hermitian Topology and Boundary Jordan Chains with Generalized Chiral Symmetry. https://arxiv.org/abs/2403.18268

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