Physical review. B, Condensed matter
Doping dependence of hole distribution in CuO2 planes of high- Tc superconductors: Local ansatz versus exact results
Jacek Dutka, Andrzej M. Oleś
Abstract
The hole distribution within a ${\mathrm{CuO}}_{2}$ plane, a common structural element of high-temperature superconductors, is investigated as a function of doping by holes. The correlated ground state of a three-band Hubbard model is found by making use of a local ansatz which includes local correlations between holes. It is found that doped holes have \ensuremath{\sim}70% oxygen character for the parameters determined from the local-density approximation, in agreement with experimental observations, while hole droplets on oxygen orbitals are formed for large copper-oxygen Coulomb repulsion, ${\mathit{U}}_{\mathit{d}\mathit{p}}$. All our results agree with those obtained from finite-cluster diagonalization.