Non-equilibrium DC noise in a Luttinger liquid with impurity

TL;DR

This paper provides an exact calculation of non-equilibrium DC noise in a Luttinger liquid with an impurity, revealing how interactions influence noise and proposing potential experimental observations in quantum Hall systems.

Contribution

It generalizes Landauer theory to interacting systems and uses Bethe ansatz to relate non-equilibrium noise to quasiparticle density fluctuations.

Findings

Exact expression for non-equilibrium DC noise derived

Noise depends on voltage, temperature, and impurity coupling as a scaling function

Results suggest possible observation in fractional quantum Hall edge tunneling

Abstract

We compute exactly the non-equilibrium DC noise in a Luttinger liquid with an impurity and an applied voltage. By generalizing Landauer transport theory for Fermi liquids to interacting, integrable systems, we relate this noise to the density fluctuations of quasiparticles. We then show how to compute these fluctuations using the Bethe ansatz. The non-trivial density correlations from the interactions result in a substantial part of the non-equilibrium noise. The final result for the noise is a scaling function of the voltage, temperature and impurity coupling. It may eventually be observable in tunneling between edges of a fractional quantum Hall effect device.