Arrays of Josephson junctions between unconventional superconductors

We study large arrays of mesoscopic junctions between gapless superconductors where the tunneling processes of both, particle-hole and Cooper, pairs give rise to a strongly retarded effective action which, contrary to the standard case, can not be readily characterized in terms of a local Josephson energy. This complexity is expected to arise in, e.g., the grain boundary and c-axis junctions in layered high-T_c superconductors. A new representation for describing collective phenomena in this system is introduced, and its phase diagram is discussed, alongside the electrical conductivity.