Accession Number : AD0761413

Title :   Deformation-Induced Anistropy of the Critical Current in Single Crystal Niobium,

Corporate Author : CORNELL UNIV ITHACA N Y MATERIALS SCIENCE CENTER

Personal Author(s) : Good,Jeremy A. ; Kramer,Edward J.

Report Date : 17 NOV 1969

Pagination or Media Count : 64

Abstract : Anisotropy of the critical current in a (110) niobium single crystal of very high purity is observed to result from tensile deformation. The critical current exhibits local maxima when the magnetic field is directed along the (1,-1,0) and (001) directions. The height of the (1,-1,0) maximum increases with respect to the height of (001) maximum as the magnetic field is decreased. The (001) maximum is sensitive to the condition of the sample surface and exhibits rectification. There is a contribution to the anisotropy of the as-deformed crystal caused by anisotropic surface roughness, which can be removed by chemical polishing. The effect of the interaction at the surface is thought to be magnified by the decrease in the flux line lattice shear modulus C66 in that region.

Descriptors :   (*NIOBIUM, SUPERCONDUCTIVITY), (*SUPERCONDUCTORS, DEFORMATION), SINGLE CRYSTALS, DISLOCATIONS, ANISOTROPY, SURFACE ROUGHNESS

Subject Categories : Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE