Percolating States in the Topological Anderson Insulator

TL;DR

This paper explores how disorder-induced topological phases in 2D insulators involve a percolation transition of bulk states, linking percolation phenomena to the stability of the topological Anderson insulator phase.

Contribution

It reveals that the delocalization in the topological Anderson insulator is driven by a percolation transition of states around disorder potential hills.

Findings

Percolation transition underpins delocalization in TAI

Bulk states circumnavigate disorder hills during transition

Disorder strength influences topological phase stability

Abstract

We investigate the presence of percolating states in disordered two-dimensional topological insulators. In particular, we uncover a close connection between these states and the so-called topological Anderson insulator (TAI), which is a topologically non-trivial phase induced by the presence of disorder. The decay of this phase could previously be connected to a delocalization of bulk states with increasing disorder strength. In this work we identify this delocalization to be the result of a percolation transition of states that circumnavigate the hills of the bulk disorder potential.