Lower critical field of an anisotropic extreme type-II superconductor

Journal Article · Sat Oct 01 00:00:00 EDT 1988 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.38.6641· OSTI ID:6824466

Klemm, R A

It is shown that the procedure of Klemm and Clem abbreviated as (I) for the transformation to isotropic form of the Ginzburg-Landau free energy for a superconductor with a general effective-mass anisotropy leads to a current which is not perpendicular to the magnetic induction B, unless B is in a crystal-symmetry direction. In general, the mean-field free energy is thus a function of a new parameter ..beta.., which depends upon the direction cosines of B, as well as a function of the renormalized kappa-tilde parameter of I, except at the upper critical field H/sub c//sub 2/. A perturbation solution in ..gamma.. = ..beta../(1+..beta..) is found to order ..gamma../sup 2/, and the angular dependence of the lower critical field H/sub c//sub 1/ is determined. The parameter ..beta.. is found to cause B to nearly lock on to a crystal-symmetry direction, so that as the external field angle is varied, B switches from near to one symmetry direction to (near to) another, yielding a kink in the angular dependence of H/sub c//sub 1/ that is more pronounced than in I.

• Research Organization: Department of Physics B-019, University of California, San Diego, La Jolla, California 92093
• OSTI ID: 6824466
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 38:10; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

656100* -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ANISOTROPY
CRITICAL FIELD
EFFECTIVE MASS
ENERGY
FREE ENERGY
GINZBURG-LANDAU THEORY
MAGNETIC FIELDS
MASS
PERTURBATION THEORY
PHYSICAL PROPERTIES
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TYPE-II SUPERCONDUCTORS