Low-Noise THz SIS Mixers Incorporating NbTiN/SiO2/Al and Al/SiO2/Al Tuning Circuits
نویسنده
چکیده
The development of the Heterodyne Instrument for the Far-Infrared (HIFI) requires lownoise SIS mixers for frequencies up to 1.25 THz. Past work has shown that the integration of a NbTiN/SiO2/Al tuning circuit with standard Nb SIS junctions enables the development of state-of-the-art heterodyne receivers for frequencies up to at least 1 THz [1-3]. Following from the results of this previous work, the design of the waveguide mixer has been optimized to obtain both high sensitivity and wide RF band-widths.
منابع مشابه
NbTiN/SiO2/NbTiN and NbTiN/SiO2/Al tuning circuits for 1 THz waveguide SIS mixers
Waveguide SIS mixers are presented in which Nb/Al-AlOx/Nb tunnel junctions are integrated with both NbTiN/SiO2/NbTiN and NbTiN/SiO2/Al tuning circuits. The mixers with a NbTiN/SiO2/NbTiN tuning circuit yield relatively low receiver noise temperatures between 700 and 830 GHz, but their sensitivity drops significantly above ~ 850 GHz. In contrast, low-noise heterodyne mixing near 1 THz is observe...
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