CHARGE-TRANSFER POLARIZATION-WAVE IN THE HIGH-TC OXIDES AND ITS RELEVANCE TO SUPERCONDUCTING PAIRING

We develop the idea of a charge-transfer polarization wave in the high-Tc oxides as high-frequency bosons originating from the long-range dipole-dipole interaction in the CuO2 planes. The dispersion relationships of the longitudinal and transverse polarization waves are derived in three and two dimensions, and the coupling of the longitudinal wave to the carriers leading to superconductive pairing is calculated. The superconducting gap equation is solved in the adiabatic (boson<F) and in the antiadiabatic (boson>F) regime in the weak-coupling case. In the latter situation superconductivity can be thought as arising from dielectric bipolarons. © 1990 The American Physical Society.