Harmonic mixing in a superconductorhyphen;insulatorhyphen;normal metal tunnel junction receiver

摘要

We have investigated the theoretical performance of a subharmonically pumped Pb/Bi/Inhyphen;oxidehyphen;Ag superconductorhyphen;insulatorhyphen;normal metal mixer and found excellent receiver noise performance for signal frequencies above the gap frequency, Dgr;/h, if the junction is biased at zero volts. This type of mixer needs no pair current suppression and can use local oscillator power more efficiently than a fundamental mixer.