STOCHASTIC QUANTIZATION OF THE 2D HUBBARD-MODEL - A NEW APPROACH TO ASSESSING THE EFFECT OF LOCAL AND NONLOCAL FIELDS IN HIGH-T-C OXIDES

A new approach was proposed for calculating matrix elements of Green's function in local and bilocal external fields for the 2D Hubbard mode l using the quantum-mechanical Monte Carlo method. This approach, comb ined with stochastic quantization, was used to determine the energy an d spin-spin correlation function [(SiSjz)-S-z] for a 4 x 4 lattice in a local field. The simulation yielded the same dependences of these qu antities on the repulsion parameter and inverse temperature as were pr edicted by earlier calculations.