Variation of T c0 in the 110 K superconductor Bi1.5Pb0.5Ca2Sr2Cu3Ox

Abstract
We have systematically investigated resistance of a bismuth cuprate Bi1.5Pb0.5Ca2Sr2Cu3Ox as a function of different annealing treatments. X‐ray diffraction and transmission electron microscopy studies were performed on concomitant specimens for correlations between structure and superconducting properties. A sharp 110 K superconducting transition was observed in the sample which was isostructural with the n=2 member of the (Bi,Pb)2(Ca,Sr)n+1CunO2n+4+δ family. The zero resistance transition temperature Tc0 was found to be sensitive to annealing at 673 K with a best result of 100 K for 30 min annealing. It is proposed that Tc0 and transition width in bismuth cuprates are sensitive to oxygen stoichiometry.