Superconductive Hot Electron Mixers with Ultra-Wide RF Bandwith for Heterodyne Receiver Applications up to 3 THz
We report on the development of quasioptical Nb hot-electron bolometer mixers for heterodyne receivers at 1.2 THz and 2.5 THz. The devices have submicron in-plane sizes, thus exploiting diffusion as the electron cooling mechanism. Quasioptical mixer circuits have been developed with planar double-dipole or twin-slot antennas. Specially designed THz test systems which avoid atmospheric absorption were used in the experiments. The measured (DSB) receiver noise temperatures are 1900K at 1.2 THz, with an esimated mixer noise temperature of 950 K, and 2750 K at 2.5 THz, with an estimated mixer noise temperature of ~900K. These results demonstrate the low-noise operation of the diffusion-cooled bolometer mixer over a wide range of frequencies up to at least 2.5 THz.
The Far Infrared and Submillimetre Universe.
- Pub Date:
- August 1997