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arXiv · 2009.04220

Non-Bloch band theory and bulk-edge correspondence in non-Hermitian systems

Kazuki Yokomizo·Shuichi Murakami
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Abstract

In this paper, we review our non-Bloch band theory in one-dimensional non-Hermitian tight-binding systems. In our theory, it is shown that in non-Hermitian systems, the Brillouin zone is determined so as to reproduce continuum energy bands in a large open chain. By using simple models, we explain the concept of the non-Bloch band theory and the method to calculate the Brillouin zone. In particular, for the non-Hermitian Su-Schrieffer-Heeger model, the bulk-edge correspondence can be established between the topological invariant defined from our theory and existence of the topological edge states.

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Kazuki Yokomizo, Shuichi Murakami. 2020-09-09. Non-Bloch band theory and bulk-edge correspondence in non-Hermitian systems. https://doi.org/10.1093/ptep/ptaa140

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