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Improvement in Superconducting Resonator Quality Factor Through Surface Passivation

ORAL

Abstract

High quality factor resonators are crucial components in photon detectors as well as many quantum computing architectures. There are two dominant mechanisms of loss in these devices. The first is due to two-level systems which mostly reside in the surface oxides. The second stems from a modification of the surface resistance due to quasiparticles within the superconductor. In this study, we characterize the effect of these loss mechanisms for Nb co-planar resonators with and without a TiN capping layer by correlating materials analysis (XPS,TEM) and low temperature electrical measurements. We find that the presence of the capping layer improves the quality factor relative to the standard resonator.

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Presenters

  • Cassidy Berk

    Lawrence Berkeley National Laboratory

Authors

  • Cassidy Berk

    Lawrence Berkeley National Laboratory

  • Archan Banerjee

    Lawrence Berkeley National Laboratory, University of California, Berkeley

  • AHMED HAJR

    Lawrence Berkeley National Laboratory

  • John Mark Kreikebaum

    Lawrence Berkeley National Laboratory, University of California, Berkeley, Univ of California – Berkeley, Physics, University of California, Berkeley

  • Virginia Altoe

    Lawrence Berkeley National Laboratory

  • David Ivan Santiago

    Lawrence Berkeley National Laboratory, University of California, Berkeley, Lawrence Berkely National Laboratory, Quantum Nanoelectronics Laboratory, Dept. of Physics, University of California, Berkeley

  • D. Frank Ogletree

    Lawrence Berkeley National Laboratory

  • Irfan Siddiqi

    Lawrence Berkeley National Laboratory, University of California, Berkeley, Univ of California - Berkeley, Univ of California – Berkeley, Quantum Nanoelectronics Lab, UC Berkeley, Physics, University of California, Berkeley, Quantum Nanoelectronics Laboratory, Dept. of Physics, University of California, Berkeley