Tunneling Model of the Superconducting Proximity Effect

Abstract

We study a simple theoretical model of the proximity effect between superposed normal and superconducting metal films. We imagine a potential barrier between the films and treat electron transmission through the barrier as a tunneling process. For thin films the model is soluble, and we can treat the BCS potential self-consistently and calculate the excitation spectrum. We compute the transition temperature, the energy gap, and the electronic density of states for comparison with tunneling experiments.