Flux flow and proximity effects in aligned Pb--Cd eutectic lamellar structures

Technical Report · Thu Sep 01 04:00:00 EDT 1977

DOI:https://doi.org/10.2172/6897466· OSTI ID:6897466

Spencer, C. R.

A high speed directional solidification technique was used to fabricate lamellar Pb-Cd and (Pb-Mg)--(Cd-Mg) superconductor-normal metal composites in which all the lamellae are oriented perpendicular to the broad surface of the sample. These lamellar composites are found to behave like a large number (approximately 1000) of superconducting-normal-superconducting junctions. For the Pb-Cd eutectic system, the critical current densities and critical fields have shown no dependence upon the lamellar periods between 1.0 and 3.1 microns. The critical current density of the aligned lamellar Pb-Cd structures was enhanced approximately 50% when compared to quenched eutectic alloy and to pure Pb. The superconducting transition temperature, T/sub c/, varies inversely with the square of the thickness of the superconducting material as expected from Ginzburg-Landau theory. Upon annealing, the Pb lamellae change from type II to type I superconductivity.

• Research Organization: AMES (Ames Laboratory (AMES), Ames, IA (United States))
• Sponsoring Organization: USDOE
• DOE Contract Number: W-7405-ENG-82
• OSTI ID: 6897466
• Report Number(s): IS-T-787
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656102 -- Solid State Physics-- Superconductivity-- Acoustic
Electronic
Magnetic
Optical
& Thermal Phenomena-- (-1987)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
CADMIUM
CRITICAL CURRENT
CRITICAL FIELD
CURRENTS
ELECTRIC CURRENTS
ELEMENTS
EUTECTICS
LAMELLAE
LEAD
MAGNETIC FIELDS
MAGNETIC FLUX
METALS
ORIENTATION
PHYSICAL PROPERTIES
PROXIMITY EFFECT
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION TEMPERATURE
TYPE-I SUPERCONDUCTORS
TYPE-II SUPERCONDUCTORS