Effect of O-O transfer upon a hole in CuO₂ planes of HTS

Abstract

The formation of spin polarons (spin-polarized clusters) in the weakly doped antiferromagnetically ordered CuO₂ planes of high-T _c cuprates is investigated. The influence of additional holes is calculated within a self-consistent mean-field approximation, by taking O-O hybridization (characterized by the parameter t) into account. It is shown that the binding energy and the polarization of clusters strongly depend on the value and the sign of t, i.e., a positive t promotes the spin polaron formation, while a negative t suppresses it. For the common value t ∼ 0.3.0.6 eV two polaron states with binding energies ∼ 0.5 eV and ∼ 0.3 eV are obtained.