Boundary conditions in the macroscopic theory of superconductivity

Glasslike low-frequency ac response ofZrB12and Nb single crystals in the surface superconducting state

“…The decrease of this ratio for temperatures in the vicinity of T c , was found in several experiments [22,24] and it was associated with the decrease of T c near the surface [25]. In the framework of the GL theory the H c3 /H c2 ratio can be changed only if (i) either T c in the surface layer differs from the bulk value, or (ii) the slope of the wave function at the surface b = − 1 Ψ ∂Ψ ∂x differs from zero [18,26]. In Fig.…”

“…It is believed that this is due to the nonzero slope of the wave function at the surface, b = − 1 Ψ ∂Ψ ∂x . The increased ratio of H c3 /H c2 shows that the sign of b is unexpectedly negative [18].…”

Current-induced giant vortex and asymmetric vortex confinement in microstructured superconductors

“…For the order parameter , it can be written as ٌ͑−iA͉͒ n =− b , where b is a real constant. 25,27,28 In this work, for simplicity, we present results assuming b = 20, although other values of the parameter b show no significant differences. The vector potential A at the boundary is determined by the external magnetic field H, with ٌ ϫ A = H. Since the external magnetic field is always parallel to the z axis we take H ϵ Hẑ.…”

Details of the thermodynamical derivation of the Ginzburg–Landau equations

“…Let us note for completeness that the boundary condition at the boundary of a superconductor and a normal metal was found by de Gennes [4] (see also [11]), but its derivation lies outside the thermodynamic theory we consider in this article.…”