Model calculations of the proximity effect in finite multilayers

The proximity-effect theory developed by Takahashi and Tachiki for infinite superconductor/normal (S/N) multilayers is applied to multilayer systems with a finite number of layers in the growth direction. The purpose is to investigate why previous applications to infinite multilayers fail to describe the measured data satisfactorily. It is shown that surface superconductivity may appear, depending on the thickness of the covering normal metallic layers, on both the top and the bottom. Most of the parameters used refer to the V/Ag system, but systems in which the N metal is also a superconductor are considered as well. The nucleation process is studied as a function of the system parameters, including the transparency of the S/N interface. (C) 2001 Academic Press.