IEICE Transactions on Electronics

Theoretical Simulation of the Mixing Performance of Distributed Superconducting Tunnel Junction Arrays at 1.2 THz

Sheng-Cai Shi, Wenlei Shan, Jing Li

Published Mar 1, 2007• 8 citations

Abstract

In this paper we focus on the numerical simulation of the mixing behaviors of distributed superconducting junction arrays at 1.2 THz. A novel type of superconducting tunnel junctions, i.e., NbN/AlN/Nb, which have a relatively high gap voltage (4.3 mV) and can reach a critical current density as high as several tens of kA/cm 2 , are proposed for this characterization along with conventional Nb/AlOx/Nb junctions. The former is incorporated with a NbN/SiO 2 /Al tuning circuit, and the latter with a Nb/SiO 2 /Al and a NbTiN/SiO 2 /Al tuning circuits. The noise performance, local-oscillator power requirement, IF bandwidth, and optimum embedding impedance are thoroughly characterized for the two types of distributed superconducting junction arrays.

DOI: 10.1093/ietele/e90-c.3.556

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