US4880771A
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Bismuth-lead-strontium-calcium-cuprate superconductors
Assignee: Nokia Bell Labs
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Filing: 1988-02-26
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Granted: 1989-11-14
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Expires: 2008-02-26
Abstract
Abstract Novel superconductive Pb-substituted oxides are disclosed. The oxides all have layered perovskite-like crystal structure, and manifest superconductivity (R=o) above about 77K. The materials are described by the nominal formula X 2+x M 3-x Cu 2 O 8 ±δ, where X is Bi and Pb, M is Sr and Ca, 0≦×≦0.3, 0≦δ≦0.5, the Pb/Bi ratio is between about 0.2 and about 0.5, and the Sr/Ca ratio is between 0.5 and 2.
Inventors
- 👤 Robert J. Cava
- 👤 Steven A. Sunshine
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:52
CPC Classifications
H; H10; H10N; H10N60/00; H10N60/80; H10N60/85; H10N60/855; H10N60/857; C; C04; C04B; C04B35/00; C04B35/01; C04B35/45; C04B35/4521; C04B35/4525; Y; Y10; Y10S; Y10S505/00; Y10S505/80; Y10S505/801; Y10S505/809; Y10S505/81
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
96 words
A superconductive element comprising an effective amount of material nominally of perovskite structure and of nominal composition X 2+x M 3-x Cu 2 O 8 ±δ, where X is Bi and Pb, M is Sr and Ca, x is equal to or greater than 0 and less than about 0.3, δ is greater than about 0 and less than about 0.5, the Pb/Bi ratio is between about 0.2 and about 0.5, the Sr/Ca ratio is between about 0.5 and about 2, and the element manifesting a transition temperature T c (R=o) of at least 77 K.
Claim 2
Dependent Claim
96 words
A superconductive element comprising an effective amount of material nominally of perovskite structure and of nominal composition X 2+x M 3-x Cu 2 O 8 ±δ, where X is Bi and Pb, M is Sr and Ca, x is equal to or greater than 0 and less than about 0.3, δ is greater than about 0 and less than about 0.5, the Pb/Bi ratio is between about 0.2 and about 0.5, the Sr/Ca ratio is between about 0.5 and about 2, and the element manifesting a transition temperature T c (R=o) of at least 77 K.
Claim 3
Dependent Claim
15 words
Superconductive element of claim 1, wherein the Sr/Ca ratio is between about 0.75 and 1.25.
References Cited (Backward Citations)
US3932315A
Cited
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