Local moment approach to multi-orbital single impurity Anderson model; application to dynamical mean-field theory

TL;DR

This paper introduces a local moment approach-based solver for multi-orbital Anderson models, applied within dynamical mean-field theory to study the Mott-Hubbard transition, offering a variational method to determine local moments.

Contribution

It develops a novel solver for multi-orbital Anderson models using a local moment approach with a variational principle, applied to dynamical mean-field theory.

Findings

Successfully applied to the multi-orbital Hubbard model

Analyzed the Mott-Hubbard metal-insulator transition

Provided a variational determination of local moments

Abstract

Using a local moment approach of Logan et al. we developed a solver for a multi-orbital single impurity Anderson model. The existence of the local moments is taken from the outset and their values are determined through variational principle by minimizing the corresponding ground state energy. The method is used to solve the dynamical mean-field equations for the multi-orbital Hubbard model. In particular, the Mott-Hubbard metal--insulator transition is addressed within this approach.