Magnetism of correlated systems: beyond LDA

A. I. Lichtenstein; M. I. Katsnelson

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Magnetism of correlated systems: beyond LDA

A. I. Lichtenstein·M. I. Katsnelson

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Abstract

A novel approach to electronic correlations in magnetic crystals which takes into account a dynamical many-body effects is present. In order to to find a frequency dependence of the electron self energy, an effective quantum-impurity many-particle problem need to be solved within the dynamical mean-field theory. The numerically exact QMC-scheme and the spin-polarized fluctuation exchange approximation are used for the self-consistent solution of this single-site many-particle problem. The calculations of effective exchange interaction parameters based on the realistic electronic structure of correlated magnetic crystals have been discussed.

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A. I. Lichtenstein, M. I. Katsnelson. 2001-03-19. Magnetism of correlated systems: beyond LDA. https://arxiv.org/abs/cond-mat/0103389

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