A planar extrapolation of the correlation problem that permits pairing
Strongly Correlated Electrons
2009-10-31 v1 Statistical Mechanics
Abstract
It was observed previously that an SU(N) extension of the Hubbard model is dominated, at large N, by planar diagrams in the sense of 't Hooft, but the possibility of superconducting pairing got lost in this extrapolation. To allow for this possibility, we replace SU(N) by U(N,q), the unitary group in a vector space of quaternions. At the level of the free energy, the difference between the SU(N)and U(N,q) extrapolations appears only to first nonleading order in N.
Cite
@article{arxiv.cond-mat/0001385,
title = {A planar extrapolation of the correlation problem that permits pairing},
author = {D. Foerster},
journal= {arXiv preprint arXiv:cond-mat/0001385},
year = {2009}
}
Comments
8 pages, 2 figures