η -pairing in the model with two-particle hybridization of conduction and localized electrons

Abstract

Within the framework of a model, that takes into account two-particle hybridization of conduction and localized electrons, the effective interaction between conduction electrons is calculated. It is shown that this interaction leads to attractive effective interaction between conduction electrons when the energy of the localized electron corresponding to the two-particle state lies in the conduction band above the Fermi energy. The magnitude of the attractive interaction is minimal for η-paired states of conduction electrons. We generalize the original η-pairing construction for the proposed model and show that the superconducting state can indeed be realised. With high probability, it is the η-pairing of conduction electrons, arising from their two-particle hybridization with localized electrons, are realized in high-temperature superconductors.