A millimetric-wave radiometer with superconducting receiver mixer.

В. А. Куликов, L.V. Matveets, V. V. Migulin

Kouta Zengyou, Taku Nakajima, Kazuji Suzuki +3 more

Roman V. Ozhegov, К. Н. Горшков, Gregory N Gol'tsman +2 more

We present the results of stability testing of a terahertz radiometer based on a superconducting receiver with a SIS tunnel junction as the mixer and a flux-flow oscillator as the local oscillator. In the continuum mode, the receiver with a noise temperature of 95 K at 510 GHz measured over the intermediate frequency (IF) passband of 4–8 GHz offered a noise equivalent temperature difference of 10 ± 1 mK at an integration time of 1 s. We offer a method to significantly increase the integration time without the use of complex measurement equipment. The receiver observed a strong signal over a final detection bandwidth of 4 GHz and offered an Allan time of 5 s.

Alexander N. Vystavkin, V. P. Koshelets, G. A. Ovsiannikov

M. A. Frerking, B. D. Hunt, Henry George LeDuc +3 more

Components for the key elements of submillimeter wave heterodyne receivers are described. The devices and components are inherently space qualifiable having low power and mass needs and exhibiting robustness. Nb and NbN superconductor insulator superconductor (SIS) tunnel junctions are selected for the nonlinear mixing element because of their robustness. NbN exhibits a large superconducting bandgap, allowing operation in excess of 1500 GHz. Both waveguide mounts, for the lower frequencies and planar antenna mixer mounts for the higher frequency range, are used. Quasi-optical components are used for frequency multiplexing and combining.

L. A. Gudkov, В. А. Куликов, V. N. Laptev +2 more