PT Journal
AU Kawamura, J
   Blundell, R
   Tong, CyE
   Gol’tsman, G
   Gershenzon, E
   Voronov, B
TI Performance of NbN lattice‐cooled hot‐electron bolometric mixers
SO J. Appl. Phys.
JI J. Appl. Phys.
PY 1996
BP 4232
EP 4234
VL 80
IS 7
DI 10.1063/1.363304
DE NbN HEB mixers
AB The heterodyne performance of lattice‐cooled hot‐electron bolometric mixers is measured at 200 GHz. Superconducting thin‐film niobium nitride strips with ∼5 nm thickness are used as waveguide mixer elements. A double‐sideband receiver noise temperature of 750 K at 244 GHz is measured at an intermediate frequency centered at 1.5 GHz with 500 MHz bandwidth and with 4.2 K device temperature. The instantaneous bandwidth for this mixer is 1.6 GHz. The local oscillator power required by the mixer is about 0.5 μW. The mixer is linear to within 1 dB up to an input power level 6 dB below the local oscillator power. A receiver incorporating a hot‐electron bolometric mixer was used to detect molecular line emission in a laboratory gascell. This experiment unambiguously confirms that the receiver noise temperature determined from Y‐factor measurements reflects the true heterodyne sensitivity.
ER