Low-noise THz-range Nb based SIS Receivers for Radio Astronomy

This repost describes our results on development of low-noise heterodyne THz receivers for ground based and space radio astronomy. Superconductor-insulator-superconductor (SIS) mixers that employ high quality Nb-based tunnel junctions are the key element of the most sensitive heterodyne THz receivers. In particular we present here the SIS receivers for frequency range 211–275 GHz and 800–950 GHz with double sideband (DSB) noise temperature of about 25 K and 220 K, respectively. The latest results on development, fabrication techniques and experimental study of the SIS receivers will be discussed.