Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators

Vissers, M. R., Weides, M. P. , Kline, J. S., Sandberg, M. and Pappas, D. P. (2012) Identifying capacitive and inductive loss in lumped element superconducting hybrid titanium nitride/aluminum resonators. Applied Physics Letters, 101(2), 022601. (doi: 10.1063/1.4730389)

Abstract

We present a method to systematically locate and extract capacitive and inductive losses in superconducting resonators at microwave frequencies by use of mixed-material, lumped element devices. In these devices, ultra-low loss titanium nitride was progressively replaced with aluminum in the inter-digitated capacitor and meandered inductor elements. By measuring the power dependent loss at 50 mK as the Al/TiN fraction in each element is increased, we find that at low electric field, i.e., in the single photon limit, the loss is two level system in nature and is correlated with the amount of Al capacitance rather than the Al inductance. In the high electric field limit, the remaining loss is linearly related to the product of the Al area times its inductance and is likely due to quasiparticles generated by stray IR radiation. At elevated temperature, additional loss is correlated with the amount of Al in the inductance, with a power independent TiN-Al interface loss term that exponentially decreases as the temperature is reduced. The TiN-Al interface loss is vanishingly small at the 50 mK base temperature.

• Item Type: Articles
• Additional Information: This work was supported by the NIST Quantum Information initiative and in part by DARPA.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Weides, Professor Martin
• Authors: Vissers, M. R., Weides, M. P., Kline, J. S., Sandberg, M., and Pappas, D. P.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: Applied Physics Letters
• Publisher: AIP Publishing
• ISSN: 0003-6951
• ISSN (Online): 1077-3118
• Published Online: 09 July 2012