Clean Proximity Systems in an Electromagnetic Field*

A Josephson junction is made of a non-superconducting material of nano-scale thickness, sandwiched between two superconducting thin films. In the superconductor electrons bind in pairs with opposite momenta and spin. The non-superconducting material considered here is a magnetic multilayer with a flexible magnetic configuration. We first present the behavior of the electron pairs as they tunnel from one superconductor to the other through the multilayer with various magnetic configurations. We then present the formalism that allows to include the effect of an externally applied time-dependent electromagnetic field on the Josephson junction. We discuss how the junction can be used as a sensor for electromagnetic radiations.