IEEE Transactions on Microwave Theory and Techniques

Characterization of low-noise quasi-optical SIS mixers for the submillimeter band

Michael C. Gaidis, Henry George LeDuc, Mei Bin, D. Miller, J. A. Stern, Jonas Stasys Zmuidzinas

Published Jul 1, 1996• 51 citations

Abstract

We report on the development of low-noise quasi-optical SIS mixers for the frequency range 400-850 GHz. The mixers utilize twin-slot antennas, two-junction tuning circuits, and Nb-trilayer junctions. Fourier-transform spectrometry has been used to verify that the frequency response of the devices is well predicted by computer simulations. The 400-850 GHz frequency band can be covered with four separate fixed-tuned mixers. We measure uncorrected double-sideband receiver noise temperatures around 5h/spl nu//k/sub B/ to 700 GHz, and better than 540 K at 808 GHz. These results are among the best reported to date for broadband heterodyne receivers.

DOI: 10.1109/22.508648

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