Anisotropic upper critical fields of disordered Nb/sub 0. 53/Ti/sub 0. 47/-Ge multilayers

Journal Article · Thu Oct 01 04:00:00 EDT 1987 · J. Low Temp. Phys.; (United States)

DOI:https://doi.org/10.1007/BF00681622· OSTI ID:5741947

Jin, B Y; Ketterson, J B; McNiff, Jr, E J; Foner, S; Schuller, I K

Studies are reported of the upper critical fields of Nb/sub 0.53/Ti/sub 0.47/-Ge multilayers consisting of thick Ge layers and varying-thickness Nb/sub 0.53/Ti/sub 0.47/ layers. Both the angular dependence and the temperature dependence of the upper critical fields indicate a dimensional crossover at a Nb/sub 0.53/Ti/sub 0.47/ layer thickness near 200 A. All the 2D samples display a cusplike upper critical field angular dependence with a sharper cusp for thinner Nb/sub 0.53/Ti/sub 0.47/ layers. The parallel upper critical fields are tentatively fitted with an expression combining the 2D field dependence of Rickayzen, the paramagnetic limiting behavior of Maki, and the disorder-related Coulomb interaction effects of Maekawa and Fukuyama. The perpendicular fields are fitted with the Maekawa, Ebisawa, and Fukuyama theory; better agreement is obtained for thinner Nb/sub 0.53/Ti/sub 0.47/ sublayers when the paramagnetic limiting effect is included.

• Research Organization: Northwestern Univ., Evanston, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5741947
• Journal Information: J. Low Temp. Phys.; (United States), Journal Name: J. Low Temp. Phys.; (United States) Vol. 69:1-2; ISSN JLTPA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360104* -- Metals & Alloys-- Physical Properties
ALLOYS
ANISOTROPY
BASIC INTERACTIONS
BCS THEORY
COHERENCE LENGTH
COULOMB SCATTERING
COUPLING
CRITICAL FIELD
DIMENSIONS
ELASTIC SCATTERING
ELECTROMAGNETIC INTERACTIONS
ELEMENTS
FILMS
GERMANIUM
INHOMOGENEOUS FIELDS
INTERACTIONS
INTERMEDIATE COUPLING
JOSEPHSON EFFECT
JUNCTIONS
L-S COUPLING
LENGTH
MAGNETIC FIELDS
METALS
NIOBIUM ALLOYS
ORDER PARAMETERS
PROXIMITY EFFECT
SCATTERING
SPUTTERING
SUPERCONDUCTING FILMS
SUPERCONDUCTING JUNCTIONS
TEMPERATURE DEPENDENCE
THICKNESS
TIN ALLOYS
ULTRALOW TEMPERATURE