Ground-state properties of the Falicov-Kimball model with correlated hopping in two dimensions

Abstract

A new numerical method, recently developed to study ground states of the Falicov-Kimball model (FKM), is used to examine the effects of correlated hopping on the ground-state properties of this model in two dimensions. It is shown that the ground-state phase diagram as well as the picture of metalinsulator transitions found for the conventional FKM (without correlated hopping) are strongly changed when the correlated hopping term is added. The effect of correlated hopping is so strong that it can induce the insulator-metal transition, even in the strong-coupling limit, where the ground states of the conventional FKM are insulating for all f-electron densities. PACS numbers.:75.10.Lp, 71.27.+a, 71.28.+d, 71.30.+h 1 1