Effect of Disorder in a Three-Dimensional Layered Chern Insulator

TL;DR

This study investigates how disorder affects a three-dimensional layered Chern insulator, revealing two distinct metallic phases and analyzing their transport properties near a quantum phase transition.

Contribution

It identifies and characterizes two metallic phases induced by disorder in a layered Chern insulator, including their conductivity behavior and phase transition details.

Findings

Discovery of diffusive metallic and Weyl semimetal phases

Finite conductivity in both phases at zero energy

Conductivity vanishes at the quantum phase transition

Abstract

We studied effects of disorder in a three dimensional layered Chern insulator. By calculating the localization length and density of states numerically, we found two distict types of metallic phases between Anderson insulator and Chern insulator; one is diffusive metallic (DM) phase and the other is renormalized Weyl semimetal (WSM) phase. We show that longitudinal conductivity at the zero energy state remains finite in the renormalizd WSM phase as well as in the DM phase, while goes to zero at a semimetal-metal quantum phase transition point between these two. Based on the Einstein relation combined with the self-consistent Born analysis, we give a conductivity scaling near the quantum transition point.