Title :
NbN hot electron bolometric mixers for terahertz receivers
Author :
Kroug, M. ; Cherednichenko, S. ; Merkel, H. ; Kollberg, E. ; Voronov, B. ; Gol´tsman, Gregory ; Huebers, H.-W. ; Richter, H.
Author_Institution :
Dept. of Microwave Electron., Chalmers Univ. of Technol., Goteborg, Sweden
fDate :
3/1/2001 12:00:00 AM
Abstract :
Sensitivity and gain bandwidth measurements of phonon-cooled NbN superconducting hot-electron bolometer mixers are presented. The best receiver noise temperatures are: 700 K at 1.6 THz and 1100 K at 2.5 THz. Parylene as an antireflection coating on silicon has been investigated and used in the optics of the receiver. The dependence of the mixer gain bandwidth (GBW) on the bias voltage has been measured. Starting from low bias voltages, close to operating conditions yielding the lowest noise temperature, the GBW increases towards higher bias voltages, up to three times the initial value. The highest measured GBW is 9 GHz within the same bias range the noise temperature increases by a factor of two
Keywords :
antireflection coatings; bolometers; hot carriers; niobium compounds; submillimetre wave mixers; submillimetre wave receivers; superconducting device noise; superconducting mixers; 1.6 to 2.5 THz; 9 GHz; NbN; NbN superconducting hot electron bolometer mixer; gain bandwidth; noise temperature; parylene antireflection coating; phonon cooling; quasi-optical mixer; sensitivity; terahertz receiver; Bandwidth; Bolometers; Coatings; Electrons; Gain measurement; Optical noise; Optical receivers; Superconducting device noise; Temperature sensors; Voltage;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
