Conserving approximations for the attractive Holstein and Hubbard models
Condensed Matter
2009-10-22 v1
Abstract
Conserving approximations are applied to the attractive Holstein and Hubbard models (on an infinite-dimensional hypercubic lattice). All effects of nonconstant density of states and vertex corrections are taken into account in the weak-coupling regime. Infinite summation of certain classes of diagrams turns out to be a quantitatively less accurate approximation than truncation of the conserving approximations to a finite order, but the infinite summation approximations do show the correct qualitative behavior of generating a peak in the transition temperature as the interaction strength increases.
Keywords
Cite
@article{arxiv.cond-mat/9402029,
title = {Conserving approximations for the attractive Holstein and Hubbard models},
author = {J. K. Freericks},
journal= {arXiv preprint arXiv:cond-mat/9402029},
year = {2009}
}
Comments
33 pages, typeset in ReVTeX, NSF-ITP-94-01