Ground states of an extended Falicov-Kimball model

We present a non-perturbative study of an extended Falicov-Kimball model in one dimension. Working within the binary alloy interpretation, we include the spin of the itinerant electrons and a Hubbard interaction to model the inter-electron correlations. We derive an effective Ising model for the atomic configuration in order to show how the Hubbard term affects the stability of the phase separated states. Furthermore, we investigate the competition between the Mott insulator state of the itinerant electrons and the checkerboard phase of the spinless Falicov-Kimball model. Copyright EDP Sciences/Società Italiana di Fisica/Springer-Verlag 2006