NORMAL STATE MAGNETISM OF Zn-DOPED AND OXYGEN DEFICIENT CaLaBaCu3O7 SUPERCONDUCTOR

Abstract

Both on-site Zn substitution and oxygen deficiencies in the CaLaBaCu 3 O 7 system decrease the superconducting transition temperature T c of the pristine sample. We observed that the normal state magnetism, measured in a field of 5 KOe, shows a Curie-Weiss behavior, in terms of a localized magnetic moment, presumably on Cu sites, in both cases. The pristine system, i.e. without Zn substitution or oxygen deficiencies, shows a weakly temperature dependent small magnetic susceptibility, in the normal state, i.e. above T c . It has been argued that the normal state magnetism of HTSC systems plays a vital role in determining the T c of these materials.