%0 Journal Article
%T Improved bandwidth of a 2 THz hot-electron bolometer heterodyne mixer fabricated on sapphire with a GaN buffer layer
%A Antipov, S.
%A Trifonov, A.
%A Krause, S.
%A Meledin, D.
%A Kaurova, N.
%A Rudzinski, M.
%A Desmaris, V.
%A Belitsky, V.
%A Goltsman, G.
%J Supercond. Sci. Technol.
%D 2019
%V 32
%N 7
%I IOP Publishing
%F Antipov_etal2019
%O exported from refbase (https://db.rplab.ru/refbase/show.php?record=1277), last updated on Fri, 07 May 2021 19:34:39 -0500
%X 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.
%K NbN HEB mixer
%K GaN buffer layer
%K sapphire substrate
%R 10.1088/1361-6668/ab137b
%U https://doi.org/10.1088/1361-6668/ab137b
%P 075003