Interacting lattice electrons with disorder in two dimensions: Numerical evidence for a metal-insulator transition with a universal critical conductivity

TL;DR

This study uses quantum Monte Carlo simulations to demonstrate a metal-insulator transition in disordered, interacting electrons on a 2D lattice, identifying a universal critical conductivity at the transition point.

Contribution

It provides numerical evidence for a disorder-driven metal-insulator transition with a universal critical conductivity in a 2D lattice electron system.

Findings

Transition from Anderson insulator to disordered metal

Universal critical dc-conductivity at transition: 1.18 ± 0.06 e^2/h

Quantum Monte Carlo simulations confirm the transition

Abstract

The dc-conductivity of electrons on a square lattice interacting with a local repulsion in the presence of disorder is computed by means of quantum Monte Carlo simulations. We provide evidence for the existence of a transition from an Anderson insulator to a correlated disordered metal with a universal value of the critical dc-conductivity \sigma_{dc,crit} = (1.18 \pm 0.06) e^{2}/h at the transition.