Theory of the Superconducting Transition Temperature and Energy Gap Function of Superposed Metal Films

Abstract

A calculation is made of the transition temperature of a film sandwich composed of two thin superposed films of different metals, only one of which is superconducting in bulk. Good quantitative agreement is obtained with existing measurements of the dependence of the transition temperature on the thicknesses of the two component films. The problem is shown to be mathematically equivalent to the simple one of the energy levels of a particle in a one-dimensional square potential well.