Physical review. B, Condensed matter
SU(2) gauge symmetry of the large- U limit of the Hubbard model
Ian K. Affleck, Z. Zou, Theodore C. Hsu, Philip Warren Anderson
Abstract
We demonstrate explicitly the SU(2) gauge invariance of the large-$U$ limit of the Hubbard model, i.e., the Heisenberg model written in terms of electron operators with a constraint of one particle per site. We use this result to demonstrate the equivalence of two apparently very different mean-field theories.