Alkaline-doped mercury cuprate superconductors

Abstract

Alkaline-doped superconductors of the formula X M.sub.2 Ca.sub.2 Cu.sub.3 O.sub.8+.alpha. are provided where X is selected from the group consisting of TI, Pb, Mo, Hg and mixtures thereof, M is selected from the group consisting of Ba, Sr and mixtures thereof, and a ranges from zero to about 0.2, and being doped with a dopant selected from the group consisting of Na and Li up to a level of up to about 12% molar ratio, based upon the amount of the element X taken as 100%. The superconductors of the invention exhibit extremely high T.sub.c onset and T.sub.cO values and have high J.sub.c properties as well. The superconductors can be fabricated at relatively low annealing temperatures (750.degree.-820.degree. C.) making them suitable for use as thin films with a variety of conventional substrates.

Dependencies are inferred from the claim text.