JOSEPHSON EQUATIONS FOR THE SIMPLEST SUPERCONDUCTING MULTILAYER SYSTEM

We extend Feynman's model of a single Josephson junction to the case o f three stacked superconducting layers. In order to derive the correct voltage-phase relation, a self consistent approach to this model is u sed. By this analysis we notice that, if the intermediate electrode is thin enough to allow the overlap of the superconducting order paramet ers of the outer layers, an additional term appears in the Josephson c urrent-phase relation. Two representative applications are presented f or these types of junctions.