Effective Onsite Interaction for Dynamical Mean-Field Theory

TL;DR

This paper introduces a new scheme to incorporate non-local polarizations into dynamical mean-field theory (DMFT) and determines effective interactions, enhancing the accuracy of modeling correlated materials.

Contribution

It systematically investigates a method to include non-local effects and derives effective onsite interactions for DMFT from first principles, applied to real materials.

Findings

Non-local polarizations cause a filling-dependent anti-screening effect.

The scheme combined with DFT provides an ab initio approach for effective interactions.

Anti-screening competes with off-site interaction screening in SrVO3.

Abstract

A scheme to incorporate non-local polarizations into the dynamical mean-field theory (DMFT) and a tailor-made way to determine the effective interaction for the DMFT are systematically investigated. Applying it to the two-dimensional Hubbard model, we find that non-local polarizations induce a non-trivial filling-dependent anti-screening effect for the effective interaction. The present scheme combined with density functional theory offers an ab initio way to derive effective onsite interactions for the impurity problem in DMFT. We apply it to SrVO3 and find that the anti-screening competes with the screening caused by the off-site interaction.