IEEE MTT-S International Microwave Symposium digest
Millimeter wave superconducting receivers
Qing Hu, C. A. Mears, P. L. Richards
Abstract
Recent work done at Berkeley on the development of millimeter-wave heterodyne mixers using superconductor-insulator-superconductor (SIS) junctions is reviewed. Two types of mixers have been developed; a conventional waveguide system using a resonant cavity and an open-structure quasioptical system using planar antennas and lenses. Using the waveguide system, the lowest mixer noise level yet obtained (within 25% of the quantum limit) at 95 GHz has been achieved. The quasioptical system has achieved a good mixer performance up to 200 GHz, and it has shown promise for use at submillimeter wavelengths.>