Josephson Effect Detectors of Microwave and Far Infrared Radiation

摘要

This contract terminates nearly ten years of Navy support for the invention and development of superconducting quasiparticle heterodyne receivers for millimeter wavelength radiation. Quantum effects such as mixer conversion gain and noise comparable to the limit set by the Heisenberg uncertainty principle have been experimentally observed. Mixer response at 36 and 90 GHz has been studied as a function of parameters such as RF and IF embedding impedance, local oscillator power, bias voltage, junction I-V curve, and operating temperature. Comparisons have been made with SIS mixer theory and good agreement has generally been found. These mixers are being used full time in heterodyne receiver systems at several radio astronomical observatories. They are the lowest noise millimeter wave receivers available today.