Substituted superconductive Bi-Sr-Ca-Cu oxide and Bi-Sr-Ca-Ln-Cu oxide compositions

Abstract

A metal oxide is provided which is represented by the compositional formula : (Bi.sub.1-x A.sup.I.sub.x).sub.2 (Sr.sub.y Ca.sub.1-y-z A.sup.II.sub.z).sub.p (Cu.sub.1-r A.sup.III.sub.r).sub.q O.sub..delta. wherein 0.ltoreq.x.ltoreq.0.5, 0.3.ltoreq.y.ltoreq.0.7, 0.ltoreq.z.ltoreq.0.5, 0.ltoreq.r.ltoreq.0.1, 1>y+z, 2>p>11, 1.ltoreq.q.ltoreq.10 and 5.4.ltoreq..delta..ltoreq.24 with the exclusion of x=z=r=0, A.sup.I is at least one element selected from In, Sb, Pb and Sn; A.sup.II is at least one element selected from Na, K, Mg, Ba, and Sn and A.sup.III is at least one element selected from Ti, V, Cu, Ni, Zr, Nb, Ta, Fe and Ru. The metal oxide may further comprise an element selected from lanthanoids and yttrium. The metal oxide material shows superconductivity at a temperature not lower than the boiling point of liquid helium.

Dependencies are inferred from the claim text.