  On the basis of spin and pairing fluctuation-exchange approximation, we study
the superconductivity in quasi-two-dimensional Hubbard model. The integral
equations for the Green's function are self-consistently solved by numerical
calculation. Solutions for the order parameter, London penetration depth,
density of states, and transition temperature are obtained. Some of the results
are compared with the experiments for the cuprate high-temperature
superconductors. Numerical techniques are presented in details. With these
techniques, the amount of numerical computation can be greatly reduced.

Superconductivity