Landau laminar intermediate state structures: surface energy between normal and superconducting domains in type I superconductors with small κ values

An expression for the surface energy at the normal-superconducting boundaries of a laminar intermediate state structure is derived as a function of a/sub s//Δ, where a/sub s/ is the width of superconducting domains and Δ the surface energy parameter. Numerical calculations show that the ratio Δ//zeta/ (/zeta/ is the coherence length) is almost constant for a/sub s//Δ larger than the limit of about 4. This value corresponds to the critical film thickness that separates the regions of type I and type II superconducting behavior