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arXiv · 1805.09632

Anomalous helical edge states in a non-Hermitian Chern insulator

Kohei Kawabata·Ken Shiozaki·Masahito Ueda
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Abstract

A non-Hermitian extension of a Chern insulator and its bulk-boundary correspondence are investigated. It is shown that in addition to the robust chiral edge states that reflect the nontrivial topology of the bulk (nonzero Chern number), anomalous helical edge states localized only at one edge can appear, which are unique to the non-Hermitian Chern insulator.

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Kohei Kawabata, Ken Shiozaki, Masahito Ueda. 2018-05-24. Anomalous helical edge states in a non-Hermitian Chern insulator. https://doi.org/10.1103/physrevb.98.165148

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