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arXiv · 1807.01760

Stable topological edge states in a non-Hermitian four-band model

C. Yuce
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Abstract

We introduce a one dimensional non-Hermitian four band tight binding lattice system. We find stable topological edge states protected by particle-hole and parity-time symmetries. We show that topological phase appears in the system. We discuss that the system can also be used as a topological laser if the gain and loss positions in a unit cell are judiciously arranged.

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C. Yuce. 2018-07-04. Stable topological edge states in a non-Hermitian four-band model. https://doi.org/10.1103/physreva.98.012111

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