Growth of ordered Tantalum films and Integration into Quantum Circuits

ORAL

Abstract

We investigate the growth of tantalum on Si and sapphire to understand the limits of atomically-ordered superconducting qubit construction. On c-plane sapphire we observe (111)-oriented bcc Ta films with residual resistivity ratios exceeding 60 in 200 nm films. We present x-ray diffraction, low temperature transport, and transmission electron microscopy studies of these films and further demonstrate resonators with low-power quality factors exceeding 106 at 10 mK, 2D and 3D transmon qubits with coherence times up to 400 us, and the production of bcc Ta airbridges.

*This work was performed under the auspices of Lawrence Livermore National Laboratory (LLNL) under Contract No. DE-AC52-07NA27344. Work at UW-Madison was supported by DE-SC0020313.

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Presenters

  • Loren D Alegria

    • Lawrence Livermore Natl Lab

Authors

  • Loren D Alegria

    • Lawrence Livermore Natl Lab

  • Kevin R Chaves

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Soohyun Im

    • University of Wisconsin-Madison
    • University of Wisconsin Madison

  • Sean R O'Kelley

    • Lawrence Livermore Natl Lab

  • Kristin M Beck

    • Lawrence Livermore National Laboratory
    • Lawrence Livermore Natl Lab

  • Alessandro R Castelli

    • Lawrence Livermore Natl Lab

  • Luis A Martinez

    • Lawrence Livermore Natl Lab

  • Alexander Baker

    • Lawrence Livermore National Laboratory

  • Yaniv J Rosen

    • Lawrence Livermore Natl Lab

  • Paul Voyles

    • University of Wisconsin Madison