Conductance and noise signatures of Majorana backscattering

TL;DR

This paper proposes a conductance and noise measurement method to detect Majorana fermion backscattering, highlighting unique signatures like half-integer Hall conductivity and noise decoupling, which are robust at finite temperatures.

Contribution

It introduces a novel experimental approach using conductance and noise signatures to identify Majorana edge states, distinct from Dirac states.

Findings

Half-integer Hall conductivity as a signature

Decoupling of thermal noise in Majorana backscattering

Robustness of signatures at finite temperature

Abstract

We propose a conductance measurement to detect the backscattering of chiral Majorana edge states. Because normal and Andreev processes have equal probability for backscattering of a single chiral Majorana edge state, there is qualitative difference from backscattering of a chiral Dirac edge state, giving rise to half-integer Hall conductivity and decoupling of fluctuation in incoming and outgoing modes. The latter can be detected through thermal noise measurement. These experimental signatures of Majorana fermions are robust at finite temperature and do not require the size of the backscattering region to be mesoscopic.