@Article{Semenov_etal2003,
author="Semenov, A. D.
and H{\"u}bers, Heinz-Wilhelm
and Richter, H.
and Birk, M.
and Krocka, M.
and Mair, U.
and Vachtomin, Yu B.
and Finkel, M. I.
and Antipov, S. V.
and Voronov, B. M.
and Smirnov, K. V.
and Kaurova, N. S.
and Drakinski, V. N.
and Gol{\textquoteright}tsman, G. N.",
title="Superconducting hot-electron bolometer mixer for terahertz heterodyne receivers",
journal="IEEE Trans. Appl. Supercond.",
year="2003",
volume="13",
number="2",
pages="168--171",
optkeywords="NbN HEB mixers",
abstract="We present recent results showing the development of superconducting NbN hot-electron bolometer mixer for German receiver for astronomy at terahertz frequencies and terahertz limb sounder. The mixer is incorporated into a planar feed antenna, which has either logarithmic spiral or double-slot configuration, and backed on a silicon lens. The hybrid antenna had almost frequency independent and symmetric radiation pattern slightly broader than expected for a diffraction limited antenna. At 2.5 THz the best 2200 K double side-band receiver noise temperature was achieved across a 1 GHz intermediate frequency bandwidth centred at 1.5 GHz. For this operation regime, a receiver conversion efficiency of -17 dB was directly measured and the loss budget was evaluated. The mixer response was linear at load temperatures smaller than 400 K. Implementation of the MgO buffer layer on Si resulted in an increased 5.2 GHz gain bandwidth. The receiver was tested in the laboratory environment by measuring a methanol emission line at 2.5 THz.",
optnote="exported from refbase (https://db.rplab.ru/refbase/show.php?record=343), last updated on Tue, 18 May 2021 12:41:52 -0500",
doi="10.1109/TASC.2003.813672",
opturl="https://doi.org/10.1109/TASC.2003.813672"
}