Major normal and superconducting parameters of high-Tcoxides

Abstract

The major normal and superconducting parameters of the high-${\mathit{T}}_{\mathit{c}}$ oxides have been evaluated. The analysis based on a Fermi-liquid approach is carried out in reciprocal space: the anisotropy of the system is reflected in the shape of the Fermi surface. The analysis is valid for any form of the Fermi curve. The small value of the Fermi energy and the Fermi velocity we obtained along with the presence of a layered structure are the key features of the cuprates. The coherence length ${\xi }_0$ is evaluated and appears to be short. The value of ${\mathit{H}}_{\mathit{c}2}$ is calculated in a self-consistent way. The method of evaluation of the strength of the electron-phonon coupling is developed and leads to a strong coupling which, however, is not sufficient to give the observed value of ${\mathit{T}}_{\mathit{c}}$. The effects of anisotropy and multigap structure are discussed.