SIS receivers fbr millimeter and submillimeter-wave detection

In this work we report the current status in our development of sensitive h eterodyne for efficient down-conversion of submillimeter-wave signals to D- band. These detectors use the strong non-linearity of Nb/Al-AlOx/Nb tunnel junctions and employ preferably quasi-optical techniques to couple local-os cillator and radio-frequency signals to the superconducting junctions via a log-periodic antenna and hyper-hemispherical lens combination. Several dev ices have been fabricated and tested.