Bandstructure meets many-body theory: The LDA+DMFT method
Abstract
Ab initio calculation of the electronic properties of materials is a major challenge for solid state theory. Whereas the experience of forty years has proven density functional theory (DFT) in a suitable, e.g. local approximation (LDA) to give a satisfactory description in case electronic correlations are weak, materials with strongly correlated, say d- or f-electrons remain a challenge. Such materials often exhibit colossal responses to small changes of external parameters such as pressure, temperature, and magnetic field, and are therefore most interesting for technical applications. Encouraged by the success of dynamical mean field theory (DMFT) in dealing with model Hamiltonians for strongly correlated electron systems, physicists from the bandstructure and many-body communities have joined forces and have developed a combined LDA+DMFT method for treating materials with strongly correlated electrons ab initio. As a function of increasing Coulomb correlations, this new approach yields a weakly correlated metal, a strongly correlated metal, or a Mott insulator. In this paper, we introduce the LDA+DMFT by means of an example, LaMnO_3 . Results for this material, including the colossal magnetoresistance of doped manganites are presented. We also discuss advantages and disadvantages of the LDA+DMFT approach.
Cite
@article{arxiv.0801.2634,
title = {Bandstructure meets many-body theory: The LDA+DMFT method},
author = {K. Held and O. K. Andersen and M. Feldbacher and A. Yamasaki and Y. -F. Yang},
journal= {arXiv preprint arXiv:0801.2634},
year = {2009}
}
Comments
Introduction of LDA+DMFT in a nutshell, as presented at the workshop ''Theory meets Industry'' Vienna, 2007. The manuscript will be published as is in the workshop's proceedings, a special issue of J. Phys. Cond. Matter. 11 pages, 4 figures (in 8 eps files)