Superconducting properties of compositionally modulated Pb/Ge thin films

Conference · Tue Apr 01 04:00:00 EST 1986

OSTI ID:6975149

Locquet, J P; Sevenhans, W; Bruynseraede, Y; Homma, H; Schuller, I K

Finely layered superconducting Pb/Ge multilayers have been made on liquid nitrogen cooled sapphire substrates with use of a mass spectrometer rate controlled electron beam evaporation scheme. Individual layer thicknesses range from 1 to 10 nm, each sample containing 50 to 100 Pb/Ge layer pairs with different Pb-to-Ge thickness ratio. An x-ray analysis showed that the samples have a superlattice structure consisting of amorphous Ge layers and (III) textured polycrystalline Pb layers. Transport studies reveal that the relationship between Tc and Pb-layers resistance is influenced by the layer thickness and the evaporation conditions. Measurements of the upper critical field versus temperature clearly show the dimensional crossover effects present in Josephson coupled two-dimensional superconductors. The maximum observed in the critical current versus field curve is related to the individual layer thickness.

• Research Organization: Argonne National Lab., IL (USA); Louvain Univ. (Belgium). Lab. voor Vaste Stof-Fysika en Magnetisme
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 6975149
• Report Number(s): CONF-860914-32; ON: DE87004679
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMORPHOUS STATE
CRITICAL FIELD
DIMENSIONS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
FILMS
GERMANIUM
LAYERS
LEAD
MAGNETIC FIELDS
METALS
PHYSICAL PROPERTIES
SUPERCONDUCTING FILMS
SUPERCONDUCTIVITY
SUPERLATTICES
THICKNESS
THIN FILMS