PT Journal
AU Yagoubov, P
   Kroug, M
   Merkel, H
   Kollberg, E
   Gol'tsman, G
   Svechnikov, S
   Gershenzon, E
TI Noise temperature and local oscillator power requirement of NbN phonon-cooled hot electron bolometric mixers at terahertz frequencies
SO Appl. Phys. Lett.
JI Appl. Phys. Lett.
PY 1998
BP 2814
EP 2816
VL 73
IS 19
DI 10.1063/1.122599
DE NbN HEB mixers; noise temperature; local oscillator power
AB In this letter, the noise performance of NbN-based phonon-cooled hot electron bolometric quasioptical mixers is investigated in the 0.55–1.1 THz frequency range. The best results of the double-sideband <cd><2018>DSB<cd><2019> noise temperature are: 500 K at 640 GHz, 600 K at 750 GHz, 850 K at 910 GHz, and 1250 K at 1.1 THz. The water vapor in the signal path causes significant contribution to the measured receiver noise temperature around 1.1 THz. The devices are made from 3-nm-thick NbN film on high-resistivity Si and integrated with a planar spiral antenna on the same substrate. The in-plane dimensions of the bolometer strip are typically 0.2Ï«2 um. The amount of local oscillator power absorbed in the bolometer is less than 100 nW.
ER