SUPERCONDUCTIVITY IN THE 2-BAND EMERY MODEL

The electron-phonon and antiferromagnetic paramagnon mechanisms of superconducting pairing in the two-band Emery model on the CuO2-plane are considered. On the basis of the equation of motion, the self-consistent system of equations is obtained. The dependences of the superconducting transition temperature, for both extended s- and d-wave pairings, on the hole concentration are calculated. It is shown that both phonons and antiferromagnetic paramagnons give rise to superconductivity in both extended s- and d-wave channels. The extended s-wave superconductivity exists for low hole concentration and nearly filled d- or p-bands, whereas the d-wave superconductivity is stable for intermediate carrier concentrations.