Quantum Coulomb Glass: Anderson localization in an interacting system

TL;DR

This paper investigates how electron-electron interactions influence localization in disordered systems, extending the concept of Anderson localization to the quantum Coulomb glass model through numerical analysis.

Contribution

It introduces a framework for understanding localization in interacting electron systems and provides numerical criteria for localization in the quantum Coulomb glass model.

Findings

Single-particle excitations near the Fermi energy become more localized due to interactions.

Quantum fluctuations allow the model to describe both localized and weakly localized regimes.

Numerical diagonalization is used to evaluate localization criteria.

Abstract

The quantum Coulomb glass model describes disordered interacting electrons on the insulating side of a metal-insulator transition. By taking quantum fluctuations into account it can describe not only the localized limit but also the weakly localized regime. We discuss several possibilities to generalize the concept of Anderson localization to interacting electron systems such as the quantum Coulomb glass and define criteria for localization. The corresponding physical quantities are calculated by numerically exact diagonalization. The results indicate that single-particle excitations close to the Fermi energy become more strongly localized under the influence of interaction.