Surface tension and kinetic coefficient for the normal/superconducting interface: Numerical results versus asymptotic analysis.

The dynamics of the normal/superconducting interface in type-I superconductors has recently been derived from the time-dependent Ginzburg-Landau theory of superconductivity. In a suitable limit these equations are mapped onto a “free-boundary” problem, in which the interfacial dynamics are determined by the diffusion of magnetic flux in the normal phase. The magnetic field at the interface satisfies a modified Gibbs-Thomson boundary condition which involves both the surface tension of the interface and a kinetic coefficient for motion of the interface. In this paper we calculate the surface tension and kinetic coefficient numerically by solving the one dimensional equilibrium Ginzburg-Landau equations for a wide range of κ values. We compare our numerical results to asymptotic expansions valid for κ ≪ 1, κ ≈ 1/ √ 2, and κ ≫ 1, in order to determine the accuracy of these expansions. 74.55.+h, 74.60.-w, 05.70.Ln Typeset using REVTEX 1