Interaction effects on random Dirac fermions

TL;DR

This paper investigates how a marginal interaction influences the universality classes of disordered Dirac fermion systems, revealing stability of some fixed points and the emergence of new critical points through renormalization group analysis.

Contribution

It introduces a detailed renormalization group analysis of interaction effects on disordered Dirac fermions, identifying stability and instability of fixed points and discovering new critical behaviors.

Findings

Certain fixed points remain stable under interaction.

Some fixed points become unstable and flow to new critical points.

Interaction induces new universality classes in disordered fermion systems.

Abstract

We study a Dirac fermion model with three kinds of disorder as well as a marginal interaction which forms the critical line of $c=1$ conformal field theory. Computing scaling equations by the use of a perturbative renormalization group method, we investigate how such an interaction affects the universality classes of disordered systems with non-interacting fermions. We show that some specific fixed points are stable against an interaction, whereas others are unstable and flow to new random critical points with a finite interaction.