Experiments with Mutually Coupled Arrays of Josephson Junctions

Abstract : This report results from a contract tasking University of Erlangen-Nuremberg as follows: The contractor shall investigate triangular arrays of Josephson tunnel junctions which have shown to be suitable for high frequency applications in the mm and sub-mm range. Yukon (AFRL) and Lin have designed an active antenna array based on 2D triangular arrays as oscillators. Synchronization between the oscillators (or sub arrays) is provided by a phase shifter consisting of a parallel Josephson junction chain. The contractor has proposed an experiment based on a circuit made of two sub-arrays coupled by the phase shifter. Radiation from two sub-arrays will be coupled into a fin-line antenna and the emitted power will be studied as a function of a phase shift provided by the Josephson junction chain placed between the sub-arrays. Alternative methods using on-chip radiation detectors will be also explored.