Topological Anderson insulators in two-dimensional non-Hermitian disordered systems
Abstract
The interplay among topology, disorder, and non-Hermiticity can induce some exotic topological and localization phenomena. Here we investigate this interplay in a two-dimensional non-Hermitian disordered Chern-insulator model with two typical kinds of non-Hermiticities, the nonreciprocal hopping and on-site gain-and-loss effects. The topological phase diagrams are obtained by numerically calculating two topological invariants in the real space, which are the disorder-averaged open-bulk Chern number and the generalized Bott index, respectively. We reveal that the nonreciprocal hopping (the gain-and-loss effect) can enlarge (reduce) the topological regions and the topological Anderson insulators induced by disorders can exist under both kinds of non-Hermiticities. Furthermore, we study the localization properties of the system in the topologically nontrivial and trivial regions by using the inverse participation ratio and the expansion of single particle density distribution.
Cite
@article{arxiv.2005.13205,
title = {Topological Anderson insulators in two-dimensional non-Hermitian disordered systems},
author = {Ling-Zhi Tang and Ling-Feng Zhang and Guo-Qing Zhang and Dan-Wei Zhang},
journal= {arXiv preprint arXiv:2005.13205},
year = {2020}
}
Comments
8 pages, 7 figures. Updated to the published version