Influence of the interplay between de Gennes boundary conditions and cubicity of Ginzburg-Landau equation on the properties of superconducting films

Abstract

Exact solutions of the Ginzburg-Landau (GL) equation for the straight film subjected at its edges to the Robin-type boundary conditions characterized by the extrapolation length Λ are analyzed with the primary emphasis on the interaction between the coefficient β of the cubic GL term and the de Gennes distance Λ and its influence on the temperature T of the strip. Very substantial role is played also the superconductivity is destroyed by the growing GL nonlinearity at some temperature T > T c , which depends on Λ, n s and β. It is proved that the concentration n (0) s transforms for the large cubicities into the density of the bulk sample.