@Article{Antipov_etal2019,
author="Antipov, S.
and Trifonov, A.
and Krause, S.
and Meledin, D.
and Kaurova, N.
and Rudzinski, M.
and Desmaris, V.
and Belitsky, V.
and Goltsman, G.",
title="Improved bandwidth of a 2 THz hot-electron bolometer heterodyne mixer fabricated on sapphire with a GaN buffer layer",
journal="Supercond. Sci. Technol.",
year="2019",
publisher="IOP Publishing",
volume="32",
number="7",
pages="075003",
optkeywords="NbN HEB mixer; GaN buffer layer; sapphire substrate",
abstract="We report on the signal-to-noise and gain bandwidth of a niobium nitride (NbN) hot-electron bolometer (HEB) mixer at 2 THz fabricated on a sapphire substrate with a GaN buffer layer. Two mixers with different DC properties and geometrical dimensions were studied and they demonstrated very close bandwidth performance. The signal-to-noise bandwidth is increased to 8 GHz in comparison to the previous results, obtained without a buffer-layer. The data were taken in a quasi-optical system with the use of the signal-to-noise method, which is close to the signal levels used in actual astrophysical observations. We find an increase of the gain bandwidth to 5 GHz. The results indicate that prior results obtained on a substrate of crystalline GaN can also be obtained on a conventional sapphire substrate with a few micron MOCVD-deposited GaN buffer-layer.",
optnote="exported from refbase (https://db.rplab.ru/refbase/show.php?record=1277), last updated on Fri, 07 May 2021 19:34:39 -0500",
doi="10.1088/1361-6668/ab137b",
opturl="https://doi.org/10.1088/1361-6668/ab137b"
}