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Spectral density functional approach to electronic correlations and magnetism in crystals

A. I. Lichtenstein·M. I. Katsnelson·G. Kotliar
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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.

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A. I. Lichtenstein, M. I. Katsnelson, G. Kotliar. 2002-11-05. Spectral density functional approach to electronic correlations and magnetism in crystals. https://arxiv.org/abs/cond-mat/0211076

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