Coherent arrays of thin-film Josephson microbridges

We have investigated two different methods of coupling between the Josephson oscillations in arrays of superconducting microbridges made of Sn and In in order to establish a single free-running coherent state. We report on experiments involving a broadband inductive coupling between pairs of microbridges, each pair constituting a dc-SQUID; and a narrow hand coupling between microbridges via resonant structures in transmission lines consisting of microstrip or slot lines. We discuss the properties of these two ways of long range coupling of Josephson weak links and evaluate their potential for high-frequency applications.