Theory of non-Abelian Fabry-Perot interferometry in topological insulators

TL;DR

This paper develops a theoretical model for non-Abelian edge state interferometry in 3D topological insulators coupled with superconductors, highlighting unique features and temperature scaling behaviors distinct from other known systems.

Contribution

It introduces a novel theory for non-Abelian interferometry in topological insulators with superconductors, emphasizing differences from fractional quantum Hall systems.

Findings

Identifies the need for a converter between charged and neutral excitations.

Predicts a temperature scaling exponent of -7/4 for conductance.

Highlights the neutrality of non-Abelian excitations in this setup.

Abstract

Interferometry of non-Abelian edge excitations is a useful tool in topological quantum computing. In this paper we present a theory of a non-Abelian edge state interferometer in a 3D topological insulator brought in proximity to an s-wave superconductor. The non-Abelian edge excitations in this system have the same statistics as in the previously studied 5/2 fractional quantum Hall (FQH) effect and chiral p-wave superconductors. There are however crucial differences between the setup we consider and these systems, like the need for a converter between charged and neutral excitations and the neutrality of the non-Abelian excitations. These differences manifest themselves in a temperature scaling exponent of -7/4 for the conductance instead of -3/2 as in the 5/2 FQH effect.