Interplay of Coulomb interaction and disorder in a two-dimensional semi-Dirac fermion system

TL;DR

This paper investigates how Coulomb interaction and quenched disorder influence the low-energy physics of a two-dimensional semi-Dirac fermion system, revealing complex quantum phase transitions and non-Fermi liquid behaviors.

Contribution

It provides a systematic renormalization group analysis of the mutual effects of Coulomb interaction and disorder in semi-Dirac systems, highlighting their impact on quantum phases.

Findings

Mutual effects of Coulomb interaction and disorder lead to quantum phase transitions.

System exhibits non-Fermi liquid behaviors at low energies.

Low-energy physics depends sensitively on interaction and disorder strength.

Abstract

It was recently found that Coulomb interaction can induce a series of nontrivial spectral and transport properties in a two-dimensional anisotropic Weyl semimetal. Different from graphehe that is basically an ordinary Fermi liquid, the Coulomb interaction in this system makes the Fermi liquid description invalid over a wide range of energy scales. We present a systematic renormalization group analysis of the interplay of Coulomb interaction and quenched disorder, and show that they have substantial mutual effects on each other, which then leads to a variety of quantum phase transitions and non-Fermi liquid behaviors. The low-energy physics of the system depends sensitively on the effective strength of Coulomb interaction and disorder.