High temperature oxide superconductor

Details High temperature oxide superconductor High temperature oxide superconductor

1993-05-27

1995-11-21

Lieberman, Paul

Superconductor technology: apparatus, material, process

High temperature , per se

Copper containing

505100, 505780, 505779, 252518, 252521, H01B 1200, H01L 3912

Patent

active

054687241

ABSTRACT:
Disclosed herein are high-temperature oxide superconductors of RBa.sub.2 Cu.sub.4 O.sub.8 type, with Ba partly replaced by Sr or Ca, or with R and Ba partly replaced by Ca and Sr, respectively, as represented by the chemical composition formula of R(Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.4 O.sub.8 or R(Ba.sub.1-z Ca.sub.z).sub.2 Cu.sub.4 O.sub.8 or (R.sub.1-x Ca.sub.x) (Ba.sub.1-y Sr.sub.y).sub.2 Cu.sub.4 O.sub.8. They exhibit superconductivity at high temperatures. Especially, the last one exhibits superconductivity at a higher temperature than the former two. All of them can be made with a less amount of Ba as a deleterious substance, and the first two have improved sinterability. The best results are obtained when they are produced by the process involving the hot hydrostatic pressure treatment of the mixture of raw materials at 850.degree.-1100.degree. C. in an atmosphere composed of an inert gas and oxygen. The process permits a wider selection of Ba raw materials.

REFERENCES:
patent: 5010054 (1991-04-01), Johansen et al.
patent: 5024992 (1991-06-01), Morris
Wada et al., "Preparation and Properties of Superconducting Y(Ba.sub.1-x Sr.sub.x).sub.2 Cu.sub.4 O.sub.8 " Physical Rev. B vol. 41, No. 6, 1 Jun. 1990.
Miyatake, "Tc Increased to 90K in YBa.sub.2 Cu.sub.4 O.sub.8 by Ca Doping", Nature vol. 341, 7 Sep. 1989, pp. 41-42.
Tokiwa et al, "Crystal Structure and Superconductivity Controlled . . . in Y.sub.1-x Ca.sub.x Ba.sub.2 Cu.sub.3 O.sub.4 and YBa.sub.2-x La.sub.x Cu.sub.3 O.sub.y ", JJAP 27(6), Jun. 1988, pp. L1009-L1012.
Wada et al, "Annealing Effect of High-Tc Superconducting Y(Ba.sub.1-x Sr).sub.2 Cu.sub.3 O.sub.7-y Ceramics," JJAP 26(9), Sep. 1987, pp. L1475-L1477.
Morris et al, "Eight New High-Temperature Superconductors with the 1:2:4 Structure," Physical Review, 39(10), 1 Apr. 1989, pp. 7347-7350.
Morris et al, "Stablity of 124, 123 and 247 Superconductors," Physica C vol. 159, 1989, pp. 287-294.
Clarke, "The Development of High-Tc Ceramic Superconductors: An Introduction," Adv. Cer. Mat. vol. 2, No. 3B, Jul. 20, 1987, pp. 273-292.
K. Shibutani et al, "Bulk Synthesis of Ln.sub.1-x Ca.sub.x Ba.sub.2 Cu.sub.4 O.sub.8 (Ln.dbd.Y,Ho) by the Oxygen-Hip Technique," Physica C 167, pp. 102-106 (1990).
R. G. Buckley et al, "Calcium-Substituted Superconducting RBa.sub.2 Cu.sub.4 O.sub.8 with T.sub.c .about.90K Prepared at One Atmosphere," Physica C 165, pp. 391-396 (1990).

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