Physica. A: Statistical and theoretical physics vol:236 issue:1-2 pages:114-122
date:LEIDEN UNIV,INST LORENTZ,NL-2300 RA LEIDEN,NETHERLANDS
We predict on the basis of the Ginzburg-Landau theory that a type-I superconductor can exhibit an interface delocalization or ''wetting'' transition, in which a macroscopically thick superconducting layer intrudes from the surface into the bulk normal phase. The condition for this transition to occur is that the superconducting order parameter \psi\(2) is enhanced at the surface. Surprisingly, the order of the wetting transition is controlled by a bulk material constant, the Ginzburg-Landau parameter kappa First-order wetting is predicted for 0 less than or equal to kappa < 0.374, and critical wetting for 0.374 < kappa < 1/root 2. The possibility of critical wetting is especially interesting because this phenomenon has largely eluded experimental verification in any system until now.