Non-Hermitian Topological Anderson Insulators
Abstract
Non-Hermitian systems can exhibit unique topological and localization properties. Here we elucidate the non-Hermitian effects on disordered topological systems by studying a non-Hermitian disordered Su-Schrieffer-Heeger model with nonreciprocal hoppings. We show that the non-Hermiticity can enhance the topological phase against disorders by increasing energy gaps. Moreover, we uncover a topological phase which emerges only under both moderate non-Hermiticity and disorders, and is characterized by localized insulating bulk states with a disorder-averaged winding number and zero-energy edge modes. Such topological phases induced by the combination of non-Hermiticity and disorders are dubbed non-Hermitian topological Anderson insulators. We also find that the system has non-monotonous localization behaviour and the topological transition is accompanied by an Anderson transition. These properties are general in other non-Hermitian models.
Cite
@article{arxiv.1908.01172,
title = {Non-Hermitian Topological Anderson Insulators},
author = {Dan-Wei Zhang and Ling-Zhi Tang and Li-Jun Lang and Hui Yan and Shi-Liang Zhu},
journal= {arXiv preprint arXiv:1908.01172},
year = {2020}
}
Comments
6+4 pages, 4+6 figures; close to the published version