Competing Orderings in an Extended Falicov-Kimball Model
Abstract
We present a Hartree-Fock study of the Falicov-Kimball model extended by both on-site and non-local hybridization. We examine the interplay between excitonic effects and the charge-density wave (CDW) instability known to exist at zero hybridization. It is found that the CDW state remains stable in the presence of finite hybridization; for on-site hybridization the Coulomb interaction nevertheless strongly enhances the excitonic average above its value in the noninteracting system. In contrast, for non-local hybridization, we observe no such enhancement of the excitonic average or a spontaneous on-site hybridization potential. Instead, we find only a significant suppression of the excitonic correlations in the CDW state. A phenomenological Ginzburg-Landau analysis is also provided to understand the interplay.
Cite
@article{arxiv.cond-mat/0506159,
title = {Competing Orderings in an Extended Falicov-Kimball Model},
author = {P. M. R. Brydon and Jian-Xin Zhu and M. Gulacsi and A. R. Bishop},
journal= {arXiv preprint arXiv:cond-mat/0506159},
year = {2009}
}
Comments
RevTex, 5 pages, 4 figures; expanded and corrected, typos added, references added