Theory of electron-exciton interaction in high-temperature superconductors

The paper is concerned with the mechanism of high-temperature superconductivity in Y-Ba-Cu-O ceramics involving the formation of local pairs at copper-oxygen chains and their interaction with band states in the copper-oxygen CuO2 planes. The local pairs are formed by holes in the filled shells of O(2-) ions, which form 'bridges' between the chains and the conducting planes. Hole attraction at adjacent oxygen ions results from the exciton transition of Cu(2+) and O(2-) ions to the virtual state Cu(+)O(-).