Temperature-dependent crossover in fractional quantum Hall edges in the presence of Coulomb interaction

TL;DR

This paper investigates how temperature influences the edge states of fractional quantum Hall systems, revealing a crossover that affects the dispersion and Coulomb interaction effects, and improves the fit to experimental conductance data.

Contribution

It introduces a microscopic fractional quantum Hall edge model that captures temperature-dependent crossover phenomena and refines the understanding of Coulomb interaction effects.

Findings

Identification of a critical temperature scale affecting edge dispersion

Better fit to tunneling experiment data with the crossover model

Suppression of Coulomb interaction effects at higher temperatures

Abstract

Based on a newly derived microscopic fractional quantum Hall edge model, we study its thermodynamics at finite temperature. For the dressed energy spectrum a critical energy scale determined by the temperature exists, below which the refractive dispersion which is essential to the model's bosonization to a Luttinger liquid is smeared. According to this observation, a temperature-dependent crossover picture is proposed, and applied to the analysis of a recent tunneling experiment in comparison with the standard Luttinger liquid theory, and a better fit to the features of the measured conductance-temperature curve is achieved. We also consider the role of the Coulomb interaction in the thermodynamics and find that a crossover exists during which the influence of the Coulomb interaction is suppressed with the increase of temperature.