%0 Conference Proceedings %T Gain bandwidth and noise temperature of NbTiN HEB mixer %A Finkel, Matvey %A Vachtomin, Yuriy %A Antipov, Sereey %A Drakinski, Vladimir %A Kaurova, Natalia %A Voronov, Boris %A Goltsman, Greeory %S Proc. 14[super:th] Int. Symp. Space Terahertz Technol. %D 2003 %F Finkel_etal2003 %O exported from refbase (https://db.rplab.ru/refbase/show.php?record=1500), last updated on Tue, 18 May 2021 17:50:09 -0500 %X We have determined that the gain bandwidth of phonon-cooled HEB mixer employing NbTiN films deposited on MgO layer over Si substrate is limited b y the escape of phonons to the substrate. The cut-off frequencies of 1 um long devices operating at T 71, based on 3.5 nm. 4 nm and 10 nm thick _films amount to 400 Mk. 300 MHz, and 100 MHz, respectivel y . The gain bandwidth of 0.13 . um long devices fabricated from 3.5 nm thick _film is larger and amounts to 0.8 GIL; at the optimal operating point and to 1.5 GIL: at larger bias. The increase of the gain bandwidth from 400 MHz up to 1.5 GH: with the change of bridge length is attributed to diffusion cooling. A double sideband noise temperature of 4000 K was obtained _for heterodyne receiver utilizing pilot NbTiN HEB mixer (not optimized for normal state resistance) operating at the local oscillator _frequency of 2.5 THz. %K NbTiN HEB mixer %U https://www.nrao.edu/meetings/isstt/2003.shtml %P 276-285