HARMONIC MIXING AT MM WAVEBAND IN A HIGH-TEMPERATURE SUPERCONDUCTING GRAIN-BOUNDARY JOSEPHSON-JUNCTION

Using a high T(c) superconducting grain boundary Josephson junction, h armonic mixing experiments in the mm waveband were carried out, aiming at as large a harmonic number and as high a signal frequency as possi ble. The dependencies of intermediate frequency output on dc bias, har monic number, frequency of local oscillator (LO), and other parameters were carefully studied. Until now, our best result was the mixing bet ween the signal at 95 GHz and the 105th harmonic of LO at about 900 MH z. Preliminary experiments using a high T(c) harmonic mixer and phase- locking loop were tried to stabilize the frequency of a mm wave source .