Topological inverse Anderson insulator

TL;DR

This paper introduces the concept of topological inverse Anderson insulators, a new topological phase where disorder induces extended bulk states and supports disorder-assisted ballistic transport, contrasting with traditional localization.

Contribution

It proposes and analyzes a novel topological phase characterized by disorder-induced extended states and ballistic transport, supported by models like the Creutz ladder and SSH chain.

Findings

Disorder can induce extended bulk states in flat-band models.

Disorder-assisted ballistic quantum transport can occur in this phase.

The phase can be realized with current experimental techniques.

Abstract

A different type of topological phase dubbed topological inverse Anderson insulators is proposed, which is characterized by the disorder-induced extended bulk states from the flat-band localization and topological edge states. Based on the topological invariant, the behaviors of the localization length of the zero-energy modes, and quantum transport, we identify its existence in several all-band-flat models with the disordered potentials or hopping including the $\pi$-flux Creutz ladder, the fully dimerized Su-Schrieffer-Heeger chain, and $\pi$-flux diamond chain. Unlike the topological Anderson insulator, where disorder induces localization and exponential suppression of transport, the disorder-assisted quantum ballistic coherent transport can appear in the topological inverse Anderson insulator. In addition, our proposal and results could be realized by the current experimental techniques.