Further studies of a laser quenched superconducting opening switch

Conference · Wed Mar 01 04:00:00 EST 1989 · IEEE Trans. Magn.; (United States)

OSTI ID:6005588

Francavilla, T L; Nelson, H H; Baronavski, A P; Wolf, S A; Gubser, D U; Hein, R A

The authors have prepared NbN films on planar sapphire, and on small diameter cylindrical quartz and sapphire substrates. Films prepared on cylindrical substrates had a greater critical current density than those prepared on planar substrates. Our highest current densities of 1X10/sup 7/ A/cm/sup 2/ were achieved on cylindrical sapphire substrates. Measurements of the laser powder required to drive the switch into the normal state were made as a function of current being carried by the NbN clad sapphire rod. These experiments indicated that near J/sub c/ very small amounts of laser energy were needed to drive the sample normal as expected. At current values well below J/sub c/ much larger energies were required. These large energies, which are roughly 10/sup 3/ larger than the condensation energy, were attributed to heating of the sapphire rod necessary to raise the NbN above its transition temperature. The desirable properties of a superconducting switch are the ability to carry large currents in the superconducting state and have a high resistance to the normal state. Considerations for using the high-T/sub c/ oxides in a superconducting switch are examined.

• Research Organization: 4563000; 1247000
• OSTI ID: 6005588
• Report Number(s): CONF-880812-
• Conference Information: Journal Name: IEEE Trans. Magn.; (United States) Journal Volume: 25:2
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360204 -- Ceramics
Cermets
& Refractories-- Physical Properties
420201* -- Engineering-- Cryogenic Equipment & Devices
656003 -- Condensed Matter Physics-- Interactions between Beams & Condensed Matter-- (1987-)
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
CORUNDUM
CRITICAL CURRENT
CURRENT DENSITY
CURRENTS
DATA
ELECTRIC CURRENTS
ELECTROMAGNETIC RADIATION
ELECTRONIC CIRCUITS
EXPERIMENTAL DATA
FABRICATION
FILMS
INFORMATION
LASER RADIATION
MINERALS
NIOBIUM COMPOUNDS
NIOBIUM NITRIDES
NITRIDES
NITROGEN COMPOUNDS
NUMERICAL DATA
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PNICTIDES
QUENCHING
RADIATIONS
REFRACTORY METAL COMPOUNDS
SAPPHIRE
SUPERCONDUCTING FILMS
SWITCHING CIRCUITS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE