Submillimeter Quasioptical Josephson Junction Oscillator With

OSCILLATORS ARE FUNDAMENTAL BUILDING BLOCKS OF MONOLITHIC SUBMILLIMETER RECEIVER SYSTEMS FOR AIRBORNE AND SATELLITE APPLICATIONS. WE PROPOSE TO RAPIDLY DEVELOP SUBMILLIMETER SUPERCONDUCTING JOSEPHSON OSCILLATORS OF 100-100000 JUNCTIONS WITH UP TO 1 MW OUTPUT POWER FOR 100 GHz-3 THz FREQUENCY RANGE. PROPOSED OSCILLATORS WOULD OFFER UNPRECEDENTED PERFORMANCE IN TERMS OF POWER, EFFICIENCY, TUNABILITY, EASE OF USAGE AND COVERAGE OF THE SUBMILLIMETER BAND. THE PROJECT IS BASED ON A NOVEL DESIGN OF THE QUASIOPTICAL JOSEPHSON OSCILLATOR THAT INCORPORATES INTEGRATED TUNING ELEMENTS AT EVERY JOSEPHSON JUNCTION/ANTENNA PAIR FOR TUNING OUT THE PARASITIC CAPACITANCE AND IMPEDANCE MATCHING BETWEEN THE JUNCTION AND THE ANTENNA. ALL JUNCTIONS ARE DC BIASED IN PARALLEL THROUGH SUPERCONDUCTING LINES TO ASSURE THE IDENTICAL OSCILLATION FREQUENCY FOR ALL JUNCTIONS. JUNCTIONS ARE LOCKED IN PHASE THROUGH INTERACTION WITH THE FABRY-PEROT TYPE CAVITY. COHERENT POWER FOR THE WHOLE ARRAY IS RADIATED IN THE BROADSIDE DIRECTION. THE GOAL OF THE PHASE I IS TO DEMONSTRATE SUBMILLIMETER JOSEPHSON OSCILLATORS IN CONDUCTUS NIOBIUM TECHNOLOGY AND TO RESOLVE IMPORTANT DESIGN ISSUES FOR FURTHER DEVELOPMENT OF SUBMILLIMETER OSCILLATORS.