Patent ID: 7608565

Claim:
A method of manufacturing a doped X—Ba—Cu—O material, the method comprising the steps of: a) mixing an X—Ba—Cu-L-O material with an X—Ba—Cu—O material; and b) crystallising the mixture; wherein each X is independently selected from a rare earth (Group IIIB) element, yttrium, a combination of rare earth elements, or a combination of yttrium and a rare earth element; and each L is one or more elements selected from U, Nb, Ta, Mo, W, Zr, Hf, Ag, Pt, Ru and Sn, wherein the X—Ba—Cu-L-O material comprise material of general formula: X w Ba x Cu y L t O z wherein each X and L is as defined hereinabove; and wherein w is 1, 2 or 3; x is 2 to 4; y is 0.1 to 1; t is 0.5 to 1; and z is 4 to 15.