Disorder-induced Majorana metal in interacting non-Abelian anyon systems

TL;DR

This paper shows that moderate disorder in 2D systems of interacting non-Abelian anyons can induce a thermal metal phase with bulk heat transport, especially relevant for quantum Hall states and topological superconductors.

Contribution

It demonstrates the emergence of a disorder-induced thermal metal phase in interacting non-Abelian anyon systems, extending understanding of phases in topological quantum systems.

Findings

Thermal metal phase forms in disordered non-Abelian anyon systems.

Bulk heat transport persists down to zero temperature in this phase.

Applicable to various systems supporting Majorana zero modes, including quantum Hall states and topological superconductors.

Abstract

We demonstrate that a thermal metal of Majorana fermions forms in a two-dimensional system of interacting non-Abelian (Ising) anyons in the presence of moderate disorder. This bulk metallic phase arises in the $\nu=5/2$ quantum Hall state when disorder pins the anyonic quasiparticles. More generally, it naturally occurs for various proposed systems supporting Majorana fermion zero modes when disorder induces the random pinning of a finite density of vortices. This includes all two-dimensional topological superconductors in so-called symmetry class D. A distinct experimental signature of the thermal metal phase is the presence of bulk heat transport down to zero temperature.