HIGH-FREQUENCY PROPERTIES OF 2-DIMENSIONAL JOSEPHSON-JUNCTION ARRAYS

Two-dimensional arrays of Josephson junctions have been shown to opera te in a state in which the microwave oscillations of the junctions are phase-coherent [1]. However, the performance of an array is strongly dependent on both the details of the load-coupling circuit and the cha racteristic parameters of the junctions. We have measured two-dimensio nal arrays of resistively shunted Josephson tunnel junctions which are capacitively coupled to a nearby detector junction. Changing the crit ical current of the junctions in our arrays, while keeping the junctio n parasitics and array coupling roughly the same, results in an unexpe cted change in device operation. We have also investigated variations of the coupling circuit. Numerical simulations of the detection circui t enable us to estimate the power output from the array and to optimiz e the parameters of the system.