TRANSPORT-PROPERTIES OF THE INFINITE-DIMENSIONAL HUBBARD-MODEL

Results for the optical conductivity and resistivity of the Hubbard model in infinite spatial dimensions are presented. At half-filling we observe a gradual crossover from a metal with a Drude peak at omega = 0 in the optical conductivity to an insulaltor as a function of U for temperatures above the antiferromagnetic phase transition. When doped, the <<insulator>> becomes a Fermi liquid with a corresponding temperature dependence of the optical conductivity and resistivity. We find a T2-coefficient in the low-temperature resistivity which suggests that the carriers in the system acquire a considerable mass-enhancement due to the strong local correlations. At high temperatures, a crossover into a semi-metallic regime takes place.