Effect of interactions on the noise of chiral Luttinger liquid systems

TL;DR

This paper investigates how interactions affect current noise in fractional quantum Hall edge states, revealing regimes where noise behaves like independent quasiparticles and others where interactions are crucial.

Contribution

It provides an exact field theoretic analysis of noise in chiral Luttinger liquids, highlighting the importance of interactions beyond the independent quasiparticle approximation.

Findings

Noise matches partition noise of Laughlin quasiparticles in certain regimes

Interaction effects are essential to accurately describe shot noise outside these regimes

Exact solutions reveal regimes where independent particle models fail

Abstract

We analyze the current noise, generated at a quantum point contact in fractional quantum Hall edge state devices, using the chiral Luttinger liquid model with an impurity and the associated exact field theoretic solution. We demonstrate that an experimentally relevant regime of parameters exists where the noise coincides with the partition noise of independent Laughlin quasiparticles. However, outside of this regime, this independent particle picture breaks down and the inclusion of interaction effects is essential to understand the shot noise.