ABSTRACT
In Chapter 16, we demonstrated the efficiency of path integral effective action techniques in describing Coulomb effects and quantum fluctuations in hybrid normal-superconducting (NS) structures. In this chapter, we will continue developing these ideas in the case of superconducting weak links, i.e., for the systems consisting of two large superconducting reservoirs connected via possibly a nonsuperconducting barrier. In Chapter 2, we already worked out an effective action description for such structures in the case of (usually very thin) insulating tunnel barriers. The presence of the Josephson effect, i.e., the possibility for a non-vanishing supercurrent to flow through a tunnel barrier between two superconductors is an important property of such systems, implications of which for a number of macroscopic quantum phenomena were explored in Chapters 4–6.
