EXACT DIAGONALIZATION APPROACH TO CORRELATED FERMIONS IN INFINITE DIMENSIONS - MOTT TRANSITION AND SUPERCONDUCTIVITY

We present a powerful method for calculating the thermodynamic propert ies of infinite-dimensional Hubbard-type models using an exact diagona lization of an Anderson model with a finite number of sites. The resol ution obtained for Green's functions is far superior to that of quantu m Monte Caxlo calculations. We apply the method to the half-filled Hub bard model for a discussion of the metal-insulator transition, and to the two-band Hubbard model where we find direct evidence for the exist ence of a superconducting instability at low temperatures.