Dynamical Mean Field Study of the Two-Dimensional Disordered Hubbard Model

TL;DR

This study uses an advanced dynamical mean-field approach to analyze how disorder and strong correlations influence localization and electronic properties in a two-dimensional Hubbard model, revealing nonmonotonic localization behavior and suppression of certain anomalies.

Contribution

It extends dynamical mean-field theory to simultaneously handle disorder and correlations in 2D, providing new insights into localization and electronic behavior without evidence of an insulator-metal transition.

Findings

Localization length varies nonmonotonically with interaction strength.

No evidence found for an insulator-metal transition.

Strong correlations suppress the Altshuler-Aronov density of states anomaly.

Abstract

We study the two-dimensional paramagnetic Anderson-Hubbard model using an extension of dynamical mean-field theory that allows us to treat disorder and strong electronic correlations on equal footing. We investigate the scaling of the inverse participation ratio at quarter- and half-filling and find a nonmonotonic dependence of the localization length on the interaction strength. We do not find evidence for an insulator-metal transition. The disorder potential becomes unscreened near the Mott transition. Furthermore, strong correlations suppress the Altshuler-Aronov density of states anomaly near half-filling.