A Nonlinear Transmission Line Model for Simulating Distributed SIS Frequency Multipliers
Journal article, 2020

Superconductor/insulator/superconductor (SIS) jun-ctions have extremely nonlinear electrical properties, which makes them ideal for a variety of applications, including heterodyne mixing and frequency multiplication. With SIS mixers, the SIS junctions normally have circular cross sections, but they can also be fabricated in the form of microstrip transmission lines, known as distributed SIS junctions (DSJs). By using a DSJ as an open-circuit stub, it is possible to create a large SIS junction with a low effective input reactance. This is beneficial for SIS frequency multipliers because their output power is proportional to the area of the junction. It is challenging, however, to simulate the behavior of DSJs because they have to be modeled as transmission lines and the model has to take into account the quasiparticle tunneling current, which is a nonlinear function of the ac voltage. In this article, we present a new nonlinear transmission line model to accurately describe the behavior of DSJs and to simulate the performance of distributed SIS frequency multipliers (DSMs). This model is compared to experimental data from a recent DSM device and good agreement is found between the dc tunneling currents and the output powers at the second harmonic. Based on this success, an improved DSM design is proposed that has a higher output power and a higher conversion efficiency than previous designs. © 2011-2012 IEEE.

nonlinear transmission line models

frequency multiplication

terahertz receivers

superconducting detectors

Distributed superconductor/insulator/superconductor (SIS) junctions (DSJs)

superconductor/insulator/superconductor (SIS) junctions

Author

John D. Garrett

University of Oxford

Hawal Marouf Rashid

Chalmers, Space, Earth and Environment, Advanced Receiver Development

G. Yassin

University of Oxford

Vincent Desmaris

University of Oxford

Alexey Pavolotskiy

University of Oxford

Victor Belitsky

University of Oxford

IEEE Transactions on Terahertz Science and Technology

2156-342X (ISSN)

Vol. 10 3 246-255 9050728

RadioNet 4

European Commission (Horizon 2020), 2017-01-01 -- 2020-12-31.

Subject Categories

Applied Mechanics

Bioinformatics (Computational Biology)

Other Electrical Engineering, Electronic Engineering, Information Engineering

DOI

10.1109/TTHZ.2020.2979125

More information

Latest update

5/29/2020