Nonlocal Dynamical Correlations of Strongly Interacting Electron Systems
Strongly Correlated Electrons
2009-10-31 v2 Superconductivity
Abstract
We introduce an extension of the dynamical mean field approximation (DMFA) which retains the causal properties and generality of the DMFA, but allows for systematic inclusion of non-local corrections. Our technique maps the problem to a self-consistently embedded cluster. The DMFA (exact result) is recovered as the cluster size goes to one (infinity). As a demonstration, we study the Falicov-Kimball model using a variety of cluster sizes. We show that the sum rules are preserved, the spectra are positive definite, and the non-local correlations suppress the CDW transition temperature. \
Keywords
Cite
@article{arxiv.cond-mat/9803295,
title = {Nonlocal Dynamical Correlations of Strongly Interacting Electron Systems},
author = {M. H. Hettler and A. N. Tahvildar-Zadeh and M. Jarrell and T. Pruschke and H. R. Krishnamurthy},
journal= {arXiv preprint arXiv:cond-mat/9803295},
year = {2009}
}
Comments
4 pages, including 4 figures The problems with convergence and causality have been positively resolved. Two figures have been changed