SPIN FLUCTUATIONS AND SUPERCONDUCTIVITY IN 2-DIMENSIONAL CUO2 SYSTEM

The dp model of the two-dimensional CuO2 system is investigated for its superconductivity and normal state properties. The normal and snomalous self-energy parts of electrons are determined self-consistently through the RPA for the exchange of spin fluctuations. We determine both parts without assuming their momentum dependences. The normal self-energy part is approximated by a linear function of the frequency variable. Quantities derived from one-body Green functions are presented in several ratios of the on-site repulsion U at copper d orbital to the energy difference Δ between copper d and oxygen p orbitals. Neighboring to the antiferromagnetic state, d-wave superconductivity takes place. Momentum dependences of the normal and anomalous self-energy parts on the copper site are similar to those in the single-band Hubbard model. © 1990, THE PHYSICAL SOCIETY OF JAPAN. All rights reserved.