GUTZWILLER WAVE-FUNCTION IN THE 3-BAND HUBBARD-MODEL - A VARIATIONAL MONTE-CARLO STUDY

The Gutzwiller wave function for the three-band Hubbard model on a two-dimensional CuO2 plane is studied by using the variational Monte Carlo (VMC) method in the limit U(d) --> infinity, where U(d) is the Coulomb repulsion between holes on a Cu site. The VMC results for the energy and the fraction of d holes are compared with those of the Rice-Ueda type Gutzwiller approximation (GA). The difference between the VMC and the GA results are most pronounced at half-filling, and away from half-filling the two results agree well in both the hole-doped and the electron-doped cases. The doping dependence of the momentum distribution function is also studied.