Reentrant localization transition in the Su-Schrieffer-Heeger model with random-dimer disorder

TL;DR

This paper investigates how random-dimer disorder affects the topological phases and localization properties of the Su-Schrieffer-Heeger model, revealing a reentrant localization transition and breakdown of bulk-boundary correspondence.

Contribution

It demonstrates the impact of random-dimer disorder on topological phase stability, edge states, and localization transitions in the SSH model, highlighting novel disorder-induced phenomena.

Findings

Absence of in-gap edge states in certain disordered phases

Reentrant localization transition behavior observed

Fractionalized end charges depend on disorder concentration

Abstract

The question of whether the topological insulators can host a stable nontrivial phase in the presence of spatially correlated disorder is a fundamental question of interest. Based on theoretical investigations, we analyze the effect of random-dimer disorder on the quantum phase transitions of the Su-Schrieffer-Heeger model. We explicitly demonstrate that, due to the absence of symmetry, there are no in-gap edge states in certain disordered topological nontrivial gapped phase and the bulk-boundary correspondence breaks down. However, the fractionalized end charges still appear at the ends of the chain. The energy distribution possibility of the in-gap edge states and the possible values of fractionalized end charges are dependent on the concentration of random-dimer disorder. On the other hand, random-dimer disorder and dimer hopping intertwine in an interesting manner. Reentrant localization transition behavior appears, which is evidenced by the fingerprint of the inverse participation ratio, normalized participation ratio, and tunneling conductivity.