PT Unknown
AU Semenov, A
   Richter, H
   Hübers, H
   Smirnov, K
   Voronov, B
   Gol'tsman, G
TI Development of terahertz superconducting hot-electron bolometer mixers
SE Proc. 6th European Conf. Appl. Supercond.
PY 2003
BP 2960
EP 2965
VL 181
DE NbN HEB mixers
AB We present recent results of the development of phonon cooled hot-electron bolometric (HEB) mixers for airborne and balloon borne terahertz heterodyne receivers. Three iomportant issues have been addresses: the quality of NbN films the HEB mixers were made from, the spectral properties of the HEB mixers and the local oscillator power required for optical operation. Studies with an atomic force microscope indicate, that the performance of the HEB mixer might have been effected by the microstructure of the NbN film. Antenna gain and noise temperature were investigated at terahertz frequencies for a HEB embedded in either log-spiral or twin-slot feed antenna. Comparison suggests that at frequencies above 3 THz the spiral feed provides better overall performance. At 1.6 THz, a power of 2.5 µW was required from the local oscillator for optimal operation of the HEB mixer.
ER