A 690 GHZ SIS Mixer

W. Hilberath, Bernd Vowinkel

Hideo Suzuki, Takeshi Imamura, Naoki Yokoyama +4 more

We have already developed a low-noise 100 GHz band (98-115 GHz) SIS mixer using Nb/AlOx/Nb junction technology. The mixer has a noise temperature of 17 K when used as a double sideband (DSB) heterodyne receiver. The SIS receiver has been in use in the 4 m radio telescope at Nagoya University for five years. As a further application of the SIS mixer, we developed middle-atmosphere ozone monitoring system using an SIS mixer for the first time. The system can measure ozone mixing ratio every 5 minutes. The integration time is less than 1/10 of the time needed in a conventional system using Schottky barrier diode (SBD) mixers. We have also begun developing developing a 200 GHz band (210-280 GHz) SIS mixer for radio astronomy and for monitoring other minor constituents such as ClO. The preliminary experiment showed that the mixer has a rather low noise temperature of 60 K (DSB).>

Anthony R. Kerr, S.-K. Pan, A. W. Lichtenberger +1 more

An integrated superconductor-insulator-superconductor (SIS) mixer for the 200-300-GHz band with no adjustable tuning is described. A waveguide input is coupled to a coplanar mixer circuit with six individually tuned SIS junctions in series. Using the best mixer, the receiver noise temperature is 45-80 K DSB over 215-275 GHz. The mixer noise temperature at 230 GHz is 12 K DSB, and the conversion loss is 2.5 dB DSB.>

Dag Winkler, A. Hodge Worsham, N. G. Ugras +3 more

Yuto Kozuki, H Ishida, Yohei Hasegawa +14 more

Jing Huang, J. Li, Shijie Huang +3 more

This paper introduces the development of a 500 GHz superconducting SIS (superconductor-insulator-superconductor) mixer, which adopts a distributed junction array of five identical Nb/AlOx/Nb SIS junctions connected in parallel. The noise performance of this 500-GHz SIS mixer is thoroughly investigated, in particular for different quasi-optical setups.