SPIN FLUCTUATION SUPERCONDUCTING PAIRING IN COPPER OXIDES

Theoretical studies of the spin fluctuation spectrum and superconducti ng pairing mediated by spin fluctuation exchange are reported with a s pecial emphasis on the results obtained for microscopic models with st rong electron correlations: the one-band Hubbard model and the t-J mod el. Phenomenological models for spin fluctuation pairing are also cons idered. The symmetry of the superconducting order parameter and the do ping dependence of superconducting transition temperature T-c obtained by numerical solutions of the strong-coupling Eliashberg equations fo r the microscopic models are discussed. The theoretical investigations presented strongly support the spin-exchange pairing mechanism in cop per oxides.