Non-Fermi liquids in the two-band extended Hubbard model

Abstract

We study the non-Fermi liquid behavior in a two-band extendedHubbard model. In the limit of infinite dimensions, whereonly local correlations are taken into account,this model in the mixed-valence regime is known to displaya metallic non-Fermi liquid phase with spin-charge separation.Here we address the effect of intersite RKKY-like interactionsusing an extended dynamical mean-field approach.We find that the spin-charge separation survivesthe quantum fluctuations associated with the intersite density-density and spin-exchange interactions.We determine the spin, charge, and single-particle correlationfunctions in the non-Fermi liquid state.