Dielectric loss of boron-based dielectrics on niobium resonators

Wisbey, D. S. et al. (2019) Dielectric loss of boron-based dielectrics on niobium resonators. Journal of Low Temperature Physics, 195(5-6), pp. 474-486. (doi: 10.1007/s10909-019-02183-w)

Abstract

Advanced solid-state quantum bits (qubits) are likely to require a variety of dielectrics for wiring crossovers, substrates, and Josephson junctions. Microwave superconducting resonators are an excellent tool for measuring the internal dielectric loss of materials. We report the dielectric loss of boron-based dielectric films using a microwave coplanar waveguide (CPW) resonator with heterostructure geometry. Power-dependent internal quality factors of magnetron-sputtered boron carbide ( B4C ) and boron nitride (BN) were measured and are compared to silicon oxide ( SiO2 ), a common material used in wiring crossovers. The internal dielectric loss due to two-level systems for B4C , and BN is less than silicon dioxide ( SiO2 ), which demonstrates the existence of low-loss sputtered materials. We also found that niobium (Nb) CPW resonators suffer a decrease in internal quality factor after deposition of B4C at temperatures above 150 ∘C . This result is consistent with the idea that the oxidation of the surface of the superconducting metal can contribute to loss in a device.

• Item Type: Articles
• Additional Information: This work was funded by the US government, Ofce of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA), and the NIST Quantum-based Sensors and Measurements Initiative. UMKC acknowledges fnancial support from the Defense Threat Reduction Agency under Grant No. HDTRA1-10-1-0092.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Weides, Professor Martin
• Authors: Wisbey, D. S., Vissers, M. R., Gao, J., Kline, J. S., Sandberg, M. O., Weides, M. P., Paquette, M.M., Karki, S., Brewster, J., Alameri, D., Kuljanishvili, I., Caruso, A. N., and Pappas, D. P.
• College/School: College of Science and Engineering > School of Engineering > Electronics and Nanoscale Engineering
• Journal Name: Journal of Low Temperature Physics
• Publisher: Springer
• ISSN: 0022-2291
• ISSN (Online): 1573-7357
• Published Online: 29 March 2019
• Copyright Holders: Copyright © 2019 Springer Science+Business Media, LLC, part of Springer Nature
• First Published: First published in Journal of Low Temperature Physics 195(5-6): 474-486
• Publisher Policy: Reproduced in accordance with the publisher copyright policy