Electronic structure and magnetic properties of correlated metals: A local self-consistent perturbation scheme

TL;DR

This paper introduces a new, computationally efficient perturbation scheme combining T-matrix and fluctuating exchange approximations within ab initio dynamical mean field theory, effectively describing electronic and magnetic properties of correlated metals.

Contribution

It proposes a novel perturbation method that reduces computational cost while accurately capturing electronic structure and exchange interactions in magnetic metals.

Findings

Effective description of electronic structure of ferromagnetic nickel.

The method provides accurate exchange interactions without vertex corrections.

The scheme is less computationally demanding than quantum Monte Carlo techniques.

Abstract

In the framework of ab initio dynamical mean field theory for realistic electronic structure calculations a new perturbation scheme which combine the T-matrix and fluctuating exchange approximations has been proposed. This method is less computationally expensive than numerically exact quantum Monte Carlo technics and give an adequate description of the electronic structure and exchange interactions for magnetic metals. We discuss a simple expression for the exchange interactions corresponding to the neglecting of the vertex corrections which becomes exact for the spin-wave stiffness in the local approximation. Electronic structure, correlation effects and exchange interactions for ferromagnetic nickel have been discussed.