NORMAL STATE AND SUPERCONDUCTING PROPERTIES OF THE 3-BAND HUBBARD-MODEL FROM QUANTUM MONTE-CARLO SIMULATIONS

A set of parameters for the three-band Hubbard model is determined by comparison of Quantum Monte Carlo results with experimental values for the charge transfer gap. With the obtained parameter set we have calculated the spectral function A(k -->, omega) for the one-particle Green's function. We find very good agreement with experimental photoemission and inverse photoemission data both for the location of the Fermi surface and for the Fermi velocity. Moreover, the interaction vertex for the pairing correlation function in the extended s-channel shows a maximum for delta approximately 20%, resembling the dependence of T(c) on doping. This feature is not present for other symmetries of the order parameter or in other parameter regions.