Possible Breakthrough for Higher Tc Discovered in Bi(Pb)2223 Practical Tapes

This is the authors' abstract. We don't add key points for this paper.

By systematic studies on the post-annealing effect in air for Bi(Pb)2223 practical tapes, T c(onset) was found to be enhanced up to 115.2 K by annealing at 680°C for 250 h from 110.2 K for an as-synthesized tape. Annealing at ∼700°C for a long time always increased the T c(onset) of the tape above 114 K, at which the generation of the Pb3221 phase simultaneously occurred during annealing. The slightly increased c-axis length was confirmed for annealed samples. The compositional change of cations in Bi(Pb)2223 during post-annealing is believed to be responsible for the T c enhancement of the present system.