Telegraph noise and the Fabry-Perot quantum Hall interferometer

TL;DR

This paper investigates how quasiparticle statistics manifest in quantum Hall Fabry-Perot interferometers, highlighting phase jumps due to anyonic and Majorana states, especially in the nonabelian nu=5/2 state.

Contribution

It provides a detailed analysis of phase jumps caused by quasiparticle entry and exit, and explores the behavior of Majorana states in small interferometers, offering insights into nonabelian statistics.

Findings

Phase jumps reveal anyonic and nonabelian quasiparticle statistics.

Parity changes in Majorana states cause characteristic pi phase jumps.

Small interferometers exhibit strong coupling of Majorana states, affecting interference patterns.

Abstract

We consider signatures of abelian and nonabelian quasiparticle statistics in quantum Hall Fabry-Perot interferometers. When quasiparticles enter and exit the interference cell, for instance due to glassy motion in the dopant layer, the anyonic phase can be observed in phase jumps. In the case of the nonabelian nu=5/2 state, if the interferometer is small, we argue that free Majorana states in the interference cell are either strongly coupled to one another or are strongly coupled to the edge. We analyze the expected phase jumps and in particular suggest that changes in the parity of the Majorana ground state should gives rise to characteristic jumps of pi in the interference phase.