PT Journal
AU Yang, ZQ
   Hajenius, M
   Baselmans, JJA
   Gao, JR
   Voronov, B
   Gol’tsman, GN
TI Reduced noise in NbN hot-electron bolometer mixers by annealing
SO Supercond. Sci. Technol.
JI Supercond. Sci. Technol.
PY 2006
BP L (9 to 12)
VL 19
IS 4
DI 10.1088/0953-2048/19/4/L01
DE NbN HEB mixers
AB We find that the sensitivity of heterodyne receivers based on superconducting hot-electron bolometers (HEBs) increases by 25–30% after annealing at 85 °C in vacuum. The devices studied are twin-slot antenna coupled mixers with a small NbN bridge of 1 × 0.15 µm2. We show that annealing changes the device properties as reflected in sharper resistive transitions of the complete device, apparently reducing the device-related noise. The lowest receiver noise temperature of 700 K is measured at a local oscillator frequency of 1.63 THz and a bath temperature of 4.3 K.
ER