ANTIFERROMAGNETIC STATE IN THE 3-BAND HUBBARD-MODEL

The antiferromagnetic (AFM) state in the three-band Hubbard model on a CuO2 plane is studied by using both the variational Monte Carlo (VMC) method based on the Gutzwiller wave function and the Rice-Ueda type G utzwiller approximation (GA). Near half-filling, the VMC energy is sig nificantly improved by introducing AFM long range order. In the AFM st ate, the VMC energy is much lower than the GA energy. The AFM phase is suppressed by the direct O-O hopping more strongly in the hole-doped case than the electron doped case.