Equations of the Ginzburg-Landau-Abrikosov-Gor'kov theory for superconductors with a state-density fine structure; effect of radiation on the upper critical field of Nb/sub 3/Sn

Journal Article · Mon Oct 01 00:00:00 EDT 1984 · Sov. Phys. - JETP (Engl. Transl.); (United States)

OSTI ID:5673118

Aleksandrov, A S; Elesin, V F; Kotov, M A; Ogurtsov, V V; Parshakov, A E; Filippov, A A

The Ginzburg-Landau-Abrikosov-Gor'kov (GLAG) theory is generalized to the case in which the electron state density has an energy fine structure and the Anderson theorem is violated. The changes in the electron spectrum in a nonideal sample cause the critical field H/sub c/2 to behave quite differently as a function of the concentration in the dirty limit than predicted by the GLAG theory with a constant state density. Specifically, H/sub c/2(0) may go through a maximum as a function of the concentration, and -(dH/sub c/2/dT)/sub T//sub c/ may increase more slowly than linearly. The energy dependence of the electron velocity near the Fermi level in a superconductor with a fine structure in the electron density disrupts the relationship between H/sub c/2(0) and (dH/sub c/2/dT)/sub T//sub c/ predicted by the GLAG theory. Samples of Nb/sub 3/Sn have been irradiated in a reactor, and H/sub c/2(T) has been measured down to liquid-helium temperatures. Direct measurements reveal that the dose dependence of H/sub c/2 at 4.2 K is nonmonotonic (it has a maximum) and that the dose dependence of (dH/sub c/2/dT)/sub T//sub c/ is nonlinear, in agreement with the theoretical predictions.

• Research Organization: Moscow Engineering Physics Institute
• OSTI ID: 5673118
• Journal Information: Sov. Phys. - JETP (Engl. Transl.); (United States), Vol. 60:4
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
NIOBIUM COMPOUNDS
CRITICAL FIELD
PHYSICAL RADIATION EFFECTS
TIN COMPOUNDS
ABRIKOSOV THEORY
ENERGY-LEVEL DENSITY
FINE STRUCTURE
GINZBURG-LANDAU THEORY
SUPERCONDUCTIVITY
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
MAGNETIC FIELDS
PHYSICAL PROPERTIES
RADIATION EFFECTS
REFRACTORY METAL COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
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