Анотація:
It is shown that the key role in the mechanism of high-Tc superconductivity in the layered
cuprate metal-oxides with anisotropic quasi-two-dimensional electronic spectrum and d-wave symmetry
of the superconducting order parameter is played by the retarded screened Coulomb interaction
and many-body correlations. We argue that the pseudogap observed in these materials is the
anisotropic dielectric gap, which appears due to the electron-hole pairing on the flat portions of
the Fermi surface in the vicinity of the extended saddle points in the quasiparticle spectrum. This
gap coexists with the superconducting gap and is partially suppressed by scattering of current carriers
on the charged point defects. The suppression of dielectric gap is analogous to the suppression
of superconducting gap by magnetic impurities in «gapless» superconductors. The complete destruction
of the pseudogap by charged impurities is assumed to increase Tc significantly.