Cluster Dual Fermion Approach to Nonlocal Correlations
Strongly Correlated Electrons
2015-05-13 v1
Abstract
We formulate a general cluster Dual Fermion Approach to nonlocal correlations in crystals. The scheme allows the treatment of long-range correlations beyond cluster DMFT and nonlocal effects in realistic calculations of multiorbital systems. We show that the the simplest approximation exactly corresponds to free cluster DMFT. We further consider the relation between the two-particle Green functions in real and dual variables. We apply this approach by calculating the Green function of the Hubbard model in one dimension starting from the two-site cluster DMFT solution. The result agrees well with the Green function obtained from a DMRG calculation.
Cite
@article{arxiv.0707.4022,
title = {Cluster Dual Fermion Approach to Nonlocal Correlations},
author = {H. Hafermann and S. Brener and A. N. Rubtsov and M. I. Katsnelson and A. I. Lichtenstein},
journal= {arXiv preprint arXiv:0707.4022},
year = {2015}
}