FERMI-LIQUID AND NON-FERMI-LIQUID PHASES OF AN EXTENDED HUBBARD-MODEL IN INFINITE DIMENSIONS

We study an extended Hubbard model in the limit of infinite dimensions. The local correlation functions of this model are those of a generalized asymmetric Anderson model. The impurity model displays a Fermi liquid phase, a phase with neither the spin nor the charge of the impurity quenched, and an intermediate phase with the spin but not the charge of the impurity quenched. This analysis establishes the existence of metallic non-Fermi-liquid phases of the lattice model over a wide range of parameters and electron densities. The non-Fermi-liquid phases describe metals with incoherent spin and/or charge excitations and self-similar local correlation functions.