Cooper instability of nonlocal spin polarons in the CuO_2 plane of high-temperature superconductors

摘要

The energy structure of nonlocal spin polarons has been obtained for the real structure of the CuO_2 plane of cuprate superconductors in the ensemble of such Fermi quasiparticles. A nonlocal spin polaron is formed due to the exchange interaction of the spin of an oxygen hole with the spins of the two nearest copper ions. The scattering amplitude of nonlocal spin polarons in the cooper channel calculated using the diagrammatic technique indicates that the spin and charge degrees of freedom are strongly correlated.