Behavior of First- and Second-Kind Superconducting Films Near Their Critical Fields

Abstract

The upper critical magnetic field of thin superconducting films has been studied as a function of its orientation with respect to the surface of the sample and as a function of the film thickness compared with $\lambda \mathrm{}\left(T\right)\mathrm{}$ and $\xi \mathrm{}\left(T\right)\mathrm{}$, for second-kind (Sn-In, In-Pb, Pb-Bi) and first-kind (Sn) materials. The results have been obtained by resistivity, dynamic-susceptibility, penetration-depth, and tunneling measurements.