Accession Number : AD0684108

Title :   CRITICAL FIELD RATIO Hc3/Hc2 FOR PURE SUPERCONDUCTORS OUTSIDE THE LANDAU-GINZBURG REGION. II. T APPROXIMATELY EQUAL TO Tc.

Descriptive Note : Technical rept.,

Corporate Author : MARYLAND UNIV COLLEGE PARK DEPT OF PHYSICS AND ASTRONOMY

Personal Author(s) : Hu,Chia-Ren ; Korenman,Victor

Report Date : FEB 1969

Pagination or Media Count : 43

Abstract : The appropriate generalization of Gor'kov's linearized gap equation for a pure, weak coupling, semiinfinite superconductor in a magnetic field, separated from vacuum or an insulator by a specularly reflecting surface, was found in a previous paper. In that paper we used the gap equation to study the surface nucleation critical field Hc3 at T approx. 0 deg. K. Here we study the region T approx. Tc and find the first three non-trivial terms in an expansion of the ratio Hc3(T)/Hc2(T) to be 1.695 (1 + 0.614 (1-t) - 0.577 (1-t) to the 3/2 power) where t is identically equal to T/Tc. The term linear in (1-t) has been found previously but the last term is new. For T close enough to Tc we show that the system is accurately described by the linearized Landau-Ginzburg equation with the usual boundary condition and thus regain the results of Saint James and de Gennes. (Author)

Descriptors :   (*SUPERCONDUCTORS, MAGNETIC FIELDS), QUANTUM THEORY, BOUNDARY VALUE PROBLEMS, TRANSITION TEMPERATURE, VANADIUM, NIOBIUM, SUPERCONDUCTIVITY, THESES

Subject Categories : Electricity and Magnetism

Distribution Statement : APPROVED FOR PUBLIC RELEASE