IEEE Transactions on Applied Superconductivity

Design and analysis of an All-NbN SIS mixer using a tuning circuit with two half-wavelength distributed junctions

Yoshinori Uzawa, Mahoto Takeda, Akira Kawakami, Zhen Wang

Published Jun 1, 2003• 7 citations

Abstract

We have designed an all-NbN superconductor-insulator-superconductor mixer with a broadband tuning circuit for the terahertz band, which enables the use of junctions with a lower current density. It uses the reactance compensation efficiently produced by two half-wavelength distributed junctions connected by a half-wavelength microstripline. Based on the design and simulated noise performance, a tuning circuit using NbN junctions with a current density of 25 kA/cm/sup 2/ should be able to cover the 780-950 GHz band with an SSB receiver noise temperature below 4hfk/sub B/.

DOI: 10.1109/tasc.2003.814002

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