Spectral density functional approach to electronic correlations and magnetism in crystals

TL;DR

This paper reviews a new approach combining LDA and DMFT for realistic electronic structure calculations, successfully describing electronic correlations and magnetism in crystals, including transition metals and high-Tc superconductors.

Contribution

It introduces a combined LDA+DMFT method with QMC solutions and discusses extensions to cluster schemes for complex magnetic and superconducting materials.

Findings

Successful description of transition metal magnetism using QMC-based DMFT.

Development of a simplified LDA+DMFT scheme with TM-FLEX approximation.

Discussion of cluster DMFT extensions for high-Tc superconductors.

Abstract

A novel approach to electronic correlations and magnetism of crystals based on realistic electronic structure calculations is reviewed. In its simplest form it is a combination of the ``local density approximation'' (LDA) and the dynamical mean field theory (DMFT) approaches. Using numerically exact QMC solution to the effective DMFT multi-orbital quantum-impurity problem, a successful description of electronic structure and finite temperature magnetism of transition metals has been achieved. We discuss a simplified perturbation LDA+DMFT scheme which combines the T-matrix and fluctuation-exchange approximation (TM-FLEX). We end with a discussion of cluster generalization of the non-local DMFT scheme and its applications to the magnetism and superconductivity of high-Tc superconductors.