Topological Anderson insulators with different bulk states in quasiperiodic chains

Abstract

We investigate the topology and localization of one-dimensional Hermitian and non-Hermitian Su-Schrieffer-Heeger chains with quasiperiodic hopping modulations. In the Hermitian case, phase diagrams are obtained by numerically and analytically calculating various topological and localization characters. We show the presence of topological extended, intermediate, and localized phases due to the coexistence of topological and localization phase transitions driven by the quasiperiodic disorder. In particular, we uncover three types of disorder-induced topological Anderson insulators (TAIs) with extended, intermediate, and localized bulk states in this chiral chain. Moreover, we study the non-Hermitian effects on the TAIs by considering two kinds of non-Hermiticities from the non-conjugate complex hopping phase and asymmetric hopping strength, respectively. We demonstrate that three types of TAIs preserve under the non-Hermitian perturbations with some unique localization and topological properties, such as the non-Hermitian real-complex and localization transitions and their topological nature.

Exact Mobility Edges and Topological Anderson Insulating Phase in a Slowly Varying Quasiperiodic Model

“…Note added: on submission of this manuscript, we notice a very recent preprint arXiv:2201:00988 entitled "Topological Anderson insulators with different bulk states in quasiperiodic chains". [65] The authors studied a similar problem, and main results of the TAI regime with the intermediate phase were obtained. In this paper, we derive the exact expression of mobility edges in this TAI phase.…”

Topological Anderson insulators induced by random binary disorders

“…Notably, TAIs are induced by the uncorrelated disorders in these studies. For instance, both uncorrelated random [26] and quasiperiodic disorders [57][58][59] can give rise to the TAI phase in 1D Su-Schrieffer-Heeger (SSH) chains. It was shown that the spatial correlations in the disorder can entirely suppress the emergence of the TAI phase on two-dimensional quantum spin Hall systems with Gaussian correlated onsite potentials [60].…”