Indirect-exchange coupling as a basic pairing mechanism of high-temperature superconductivity: Quantitative analysis of in electron-doped and

A quantitative analysis of critical temperatures for the cuprate and the cuprate is carried through on the basis of an earlier proposed, first-principle, indirect-exchange mechanism of pairing between conduction electrons (quasiparticles) mediated by closed-shell oxygen anions. We conjecture a two-component (two-phase) description for these systems, one component stable at low doping, the other at higher doping content. It is found that , including the two-plateau structure, is accurately reproduced for both systems. Doping dependence of the quasiparticle Fermi-vector length appears to determine of the Nd-compound to a high degree of accuracy. On the other hand, in the development of with oxygen deficiency depends sensitively also on the density of oxygen anions as Cooper-pair mediators. A detailed analysis of these separate effects is given. In conformity with earlier applications of the same formalism, the present results strongly indicate indirect-exchange pairing as a basic mechanism in high- cuprate superconductivity.