Multiple scattering formalism for correlated systems: A KKR+DMFT approach

TL;DR

This paper introduces a self-consistent computational scheme combining KKR multiple scattering theory with DMFT to study correlated systems, enabling the treatment of local quantum and disorder fluctuations simultaneously.

Contribution

The paper develops a novel KKR+DMFT approach that incorporates local self-energy into multiple scattering calculations for correlated and disordered materials.

Findings

Successfully applied to Fe, Ni, and FeNi alloys.

Captures local quantum fluctuations and disorder effects.

Provides a unified framework for correlated and disordered systems.

Abstract

We present a charge and self-energy self-consistent computational scheme for correlated systems based on the Korringa-Kohn-Rostoker (KKR) multiple scattering theory with the many-body effects described by the means of dynamical mean field theory (DMFT). The corresponding local multi-orbital and energy dependent self-energy is included into the set of radial differential equations for the single-site wave functions. The KKR Green's function is written in terms of the multiple scattering path operator, the later one being evaluated using the single-site solution for the $t$-matrix that in turn is determined by the wave functions. An appealing feature of this approach is that it allows to consider local quantum and disorder fluctuations on the same footing. Within the Coherent Potential Approximation (CPA) the correlated atoms are placed into a combined effective medium determined by the dynamical mean field theory (DMFT) self-consistency condition. Results of corresponding calculations for pure Fe, Ni and Fe$_{x}$Ni$_{1-x}$ alloys are presented.