Decoupling method for dynamical mean field theory calculations

TL;DR

This paper introduces a decoupling method as an impurity solver for dynamical mean field theory, demonstrating its efficiency and accuracy in modeling strongly correlated materials and enabling practical material simulations.

Contribution

The paper presents a novel, simple, and computationally efficient decoupling approach as an impurity solver within DMFT, validated against exact methods and applicable to real material studies.

Findings

Accurately reproduces spectra with quasiparticle peaks and Hubbard bands

Works efficiently across a wide parameter range

Suitable for real material simulations using LDA+DMFT

Abstract

In this paper we explore the use of an equation of motion decoupling method as an impurity solver to be used in conjunction with the dynamical mean field self-consistency condition for the solution of lattice models. We benchmark the impurity solver against exact diagonalization, and apply the method to study the infinite $U$ Hubbard model, the periodic Anderson model and the $pd$ model. This simple and numerically efficient approach yields the spectra expected for strongly correlated materials, with a quasiparticle peak and a Hubbard band. It works in a large range of parameters, and therefore can be used for the exploration of real materials using LDA+DMFT.