Reentrant Localization Transitions in a Topological Anderson Insulator: A Study of a Generalized Su-Schrieffer-Heeger Quasicrystal

TL;DR

This paper investigates a generalized SSH model with quasi-periodic hopping, revealing that disorder-induced topological phases can be robust and exhibit reentrant localization transitions, which can be observed in cold atom experiments.

Contribution

It introduces a generalized SSH model showing robust topological Anderson insulator phases and reentrant localization transitions due to quasi-periodic modulations.

Findings

Topological Anderson insulator phases can be induced by off-diagonal quasi-periodic modulations.

Reentrant topological Anderson insulator phases are robust against arbitrary modulation amplitudes.

Reentrant localization transitions are linked to TAI/RTAI and observable in cold atom systems.

Abstract

We study the topology and localization properties of a generalized Su-Schrieffer-Heeger (SSH) model with a quasi-periodic modulated hopping. It is found that the interplay of off-diagonal quasi-periodic modulations can induce topological Anderson insulator (TAI) phases and reentrant topological Anderson insulator (RTAI), and the topological phase boundaries can be uncovered by the divergence of the localization length of the zero-energy mode. In contrast to the conventional case that the TAI regime emerges in a finite range with the increase of disorder, the TAI and RTAI are robust against arbitrary modulation amplitude for our system. Furthermore, we find that the TAI and RTAI can induce the emergence of reentrant localization transitions. Such an interesting connection between the reentrant localization transition and the TAI/RTAI can be detected from the wave-packet dynamics in cold atom systems by adopting the technique of momentum-lattice engineering.