Heating effects and frequency shifts in a six-qubit Si/SiGe quantum processor

ORAL

Abstract

As spin-based quantum processors grow in size and complexity, maintaining high fidelities and minimizing crosstalk will be essential for the successful implementation of quantum algorithms and error-correction protocols. In particular, recent experiments have highlighted pernicious transient qubit frequency shifts associated with microwave qubit control. Workarounds for small devices, including pre-pulsing with an off-resonant microwave burst to bring a device to a steady-state, wait times prior to measurement, and qubit-specific calibrations all bode ill for device scalability. Here, we make substantial progress in understanding and overcoming this effect. First, in a six-qubit silicon quantum processor, we report a surprising non-monotonic relation between device temperature and qubit frequency, with frequency shifts of a similar magnitude as those induced by microwave driving. Possible mechanisms are discussed. Second, we evaluate the robustness of rf-reflectometry in the context of heating. Last, we find a pragmatic solution to the heating effect: raising the device operating temperature to about 200 mK. We show this leads to stable qubit frequencies and eliminates the need for pre-pulsing and wait times without compromising qubit coherence.

*We acknowledge support from the Army Research Office (ARO), Intel, and a European Union QLSI grant.

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Presenters

  • Brennan Undseth

    • QuTech, TU Delft
    • QuTech

Authors

  • Brennan Undseth

    • QuTech, TU Delft
    • QuTech

  • Oriol Pietx-Casas

    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech

  • Eline Raymenants

    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech

  • Mohammad Mehmandoost

    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology

  • Mateusz T Madzik

    • Delft University of Technology
    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology
    • Intel
    • University of New South Wales
    • QuTech

  • Stephan G Philips

    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology
    • Delft University of Technology

  • Sergey V Amitonov

    • TNO, Qutech
    • QuTech and TNO, Stieltjesweg 1, 2628 CK Delft, The Netherlands
    • QuTech and Netherlands Organization for Applied Scientific Research (TNO), Delft, The Netherlands
    • TNO, QuTech
    • TNO
    • TNO/QuTech

  • Sander L de Snoo

    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology

  • Larysa Tryputen

    • TNO, Qutech
    • Netherlands Organisation for Applied Scientific Research (TNO)
    • QuTech and Netherlands Organization for Applied Scientific Research (TNO), Delft, The Netherlands
    • TNO
    • TNO/QuTech
    • TNO Netherlands Organization for Applied Scientific Research

  • Amir Sammak

    • TNO, Qutech
    • QuTech and TNO, Stieltjesweg 1, 2628 CK Delft, The Netherlands
    • Netherlands Organisation for Applied Scientific Research (TNO)
    • QuTech and Netherlands Organization for Applied Scientific Research (TNO), Delft, The Netherlands
    • TNO, QuTech
    • TNO
    • Netherlands Organization for Applied Scientific Research (TNO)
    • QuTech and Netherlands Organisation for Applied Scientific Research (TNO), Stieltjesweg 1, 2628 CK Delft, The Netherlands
    • TNO/QuTech

  • Giordano Scappucci

    • QuTech and Kavli Institute of Nanoscience, TU Delft, P.O. Box 5046, 2600 GA Delft, The Netherlands
    • Delft University of Technology
    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology
    • TU Delft QuTech
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands

  • Lieven M Vandersypen

    • Delft University of Technology
    • QuTech and the Kavli Institute of Nanoscience, Delft University of Technology