TY  - CONF
AU  - Yang, Z. Q.
AU  - Hajenius, M.
AU  - Baselmans, J. J. A.
AU  - Gao, J. R.
AU  - Klapwijk, T. M.
AU  - Voronov, B.
AU  - Gol’tsman, G.
PY  - 2005
DA  - 2005//
TI  - Improved sensitivity of NbN hot electron bolometer mixers by vacuum baking
T2  - Proc. 16[super:th] Int. Symp. Space Terahertz Technol.
BT  - Proc. 16[super:th] Int. Symp. Space Terahertz Technol.
SP  - 222
EP  - 225
KW  - NbN HEB mixer
AB  - We find that the sensitivity of heterodyne receivers based on superconducting hot-electron bolometer (HEB) in- creases by 25 − 30% after baking at 85 o C and in a high vacuum. The devices studied are twin-slot antenna coupled HEB mixers with a small NbN bridge of 1×0.15 μm 2 . The mixer noise temperature, gain, and resistance versus temperature curve of a HEB before and after baking are compared and analyzed. We show that baking reduces the intrinsic noise of the mixer by 37 % and makes the superconducting transition of the bridge and the contacts sharper. We argue that the reduction of the noise is due to the improvement of the transparency of the contact/film interface. The lowest receiver noise temperature of 700 K is measured at a local oscillator frequency of 1.63 THz and a bath temperature of 4.3 K.
UR  - https://www.nrao.edu/meetings/isstt/2005.shtml
N1  - exported from refbase (https://db.rplab.ru/refbase/show.php?record=1471), last updated on Mon, 17 May 2021 18:37:04 -0500
ID  - Yang_etal2005
ER  -