Modeling and Testing Superconducting Artificial CPW Lines Suitable for Parametric Amplification

IEEE Transactions on Applied Superconductivity, vol. 34, pp. 1–8

Abstract

Achieving amplification with high gain and quantum-limited noise is a difficult problem to solve. Parametric amplification using a superconducting transmission line with high kinetic inductance is a promising technology not only to solve this problem but also adding several benefits. Compared to other technologies, they have the potential to improve power saturation, achieve larger fractional bandwidths, and operate at higher frequencies. In this type of amplifier, the selection of the proper transmission line is a key element in its design. Given current fabrication limitations, traditional lines such as coplanar waveguides (CPW), are not ideal for this purpose, since it is difficult to make them with the proper characteristic impedance for good matching and slow enough phase velocity for making them more compact. Capacitively loaded lines, also known as artificial lines, are a good solution to this problem. However, few design rules or models have been presented to guide their accurate design. This fact is even more crucial considering that they are usually fabricated in the form of Floquet lines that have to be designed carefully to suppress undesired harmonics appearing in the parametric process. In this article we present, first, a new modeling strategy, based on the use of electromagnetic-simulation software, and, second, a first-principles model that facilitate and speed the design of CPW artificial lines and of Floquet lines made out of them. Then, we present comparisons with experimental results that demonstrate their accuracy. Finally, the theoretical model allows one to predict the high-frequency behavior of the artificial lines, showing that they are good candidates for implementing parametric amplifiers above 100 GHz.

Authors 6

1. Fausto Patricio Mena

   National Radio Astronomy Observatory

   Affiliation as printed

   Central Development Laboratory, National Radio Astronomy Observatory, Charlottesville, VA, USA

   Central Development Laboratory, National Radio Astronomy Observatory, 1180 Boxwood Estate Rd, Charlottesville, VA, USA

2. Francisco Pizarro

   Pontificia Universidad Católica de Valparaíso

   Affiliation as printed

   Escuela de Ingeniería Eléctrica, Pontificia Universidad Católica de Valparaíso, Valparaiso, Chile

3. Boon-Kok Tan

   University of Oxford

   Affiliation as printed

   Department of Physics (Astrophysics), University of Oxford, Oxford, U.K

   Department of Physics (Astrophysics), University of Oxford, Denys Wilkinson Building, Keble Road, Oxford, U.K

4. David J. Thoen Aachen Instrument Science Group—Litho Netherlands Institute for Space Research

   Space Research Organisation Netherlands

   Affiliation as printed

   Instrument Science Group—Litho, Netherlands Institute for Space Research (SRON), Leiden, The Netherlands

   Netherlands Institute for Space Research (SRON), Instrument Science Group - Litho, Niels Bohrweg 4, Leiden, CA, The Netherlands

5. J. J. A. Baselmans Aachen Instrument Science Group—Litho Netherlands Institute for Space Research

   Space Research Organisation Netherlands · Delft University of Technology

   Affiliation as printed

   Instrument Science Group—Litho, Netherlands Institute for Space Research (SRON), Leiden, The Netherlands

   Department of Electrical Engineering, Faculty of Mathematics and Computer Science (EEMCS), Delft University of Technology, Mekelweg 4, Delft, CD, The Netherlands

   Netherlands Institute for Space Research (SRON), Instrument Science Group - Litho, Niels Bohrweg 4, Leiden, CA, The Netherlands

6. Ricardo Finger

   University of Chile

   Affiliation as printed

   Astronomy Department, Faculty of Physical and Mathematical Sciences, University of Chile, Santiago, Chile

   Astronomy Department, Faculty of Physical and Mathematical Sciences, University of Chile, Camino El Observatorio, Santiago, Chile