English

Low-energy states for correlated-electron models in the strong-coupling limit

Condensed Matter 2009-10-28 v1

Abstract

We study a class of exactly solvable models for strongly correlated electrons, defined on a set of N cells, and with infinite on-site repulsion on part of the sites of each cell. For 2N or more electrons the exact ground state is known. We construct a tractable (2N-1)-particle state which becomes asymptotically degenerate to the ground state in the thermodynamic limit for one special D-dimensional model. For other models, that state may be used to calculate variational upper bounds on the ground-state energy. For a Hubbard chain with three sites per unit cell, the analytical bound is compared to numerically exact results.

Keywords

Cite

@article{arxiv.cond-mat/9511033,
  title  = {Low-energy states for correlated-electron models in the strong-coupling limit},
  author = {Andreas Giesekus and Uwe Brandt},
  journal= {arXiv preprint arXiv:cond-mat/9511033},
  year   = {2009}
}

Comments

6 pages, RevTeX 3.0; 2 postscript figures, uuencoded and compressed (uufiles) accepted for publication in Phys. Rev. B