Theoretical study of electronic states and excitation spectra in Ni-substituted cuprates

Tsutsui, Kenji; Toyama, Takami*; Maekawa, Sadamichi

Impurity substitution for copper in high-Tc cuprate superconductors has attracted much attention. For Ni substitution, it has been argued from several experiments that hole carriers are strongly localized at around Ni sites. We have demonstrated theoretically that a hole can be bound in the NiO plaquette forming the Zhang-Rice doublet. In this study, we examine the interaction between the Zhang-Rice doublet and hole carriers. We carry out the numerically exact diagonalization on small clusters of the d-p model with a Ni impurity site and calculate the resonant inelastic X-ray scattering spectra for Ni K-edge.