New superconductors come through

Journal Article · Fri Jun 17 00:00:00 EDT 1988 · Science (Washington, D.C.); (United States)

OSTI ID:6621614

Recently reported advances in thallium- and bismuth-based superconducting materials are reported. Workers at Sandia National Laboratory in Albuquerque, NM have produced a thin film from a thallium-based superconductor that loses resistance to electric current at 97 K and carries as much as 110,000 amp/cm/sup 2/ at 77 K. These films are predicted to carry more current if the 2223 phase (Tl/sub 2/Ca/sub 2/Ba/sub 2/Cu/sub 3/O/sub 10/) were used instead of the 2122 phase (Tl/sub 2/CaBa/sub 2/Cu/sub 2/O/sub 8/) since the 2223 phase has a critical temperature some 15 K higher than the 2122 phase, and there should be a corresponding increase in critical current. IBM has produced polycrystalline thallium thin films that show critical temperature up to 120 K, but the critical current densities are lower than those achieved at Sandia. This is probably due to films being not as clean as those at Sandia. At Stanford, thin fibers of a bismuth-based superconductor with a critical current density as high as 50,000 amp/cm/sup 2/ at 68 K have been produced by a laser-heated pedestal growth technique. These advances should help to bring the practical application of high-temperature superconductors closer to reality.

• OSTI ID: 6621614
• Journal Information: Science (Washington, D.C.); (United States), Journal Name: Science (Washington, D.C.); (United States) Vol. 240; ISSN SCIEA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201* -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BISMUTH COMPOUNDS
CALCIUM COMPOUNDS
CHEMICAL PREPARATION
COPPER COMPOUNDS
CRITICAL CURRENT
CRITICAL TEMPERATURE
CURRENTS
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRICAL PROPERTIES
FILMS
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SUPERCONDUCTIVITY
SYNTHESIS
THALLIUM COMPOUNDS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE