Characterization of gate fidelities in a Si/SiGe two-qubit device

ORAL

Abstract

Various candidate implementations for future quantum computers have been investigated over the past twenty years. Silicon spin qubits show great promise [1] for their long coherence times and integration using semiconductor technology but there have been very few quantitative studies of the fidelities of two-qubit gates. Here we characterize the gate fidelities of a C-Phase gate using randomized benchmarking. For single-qubit gates, we perform randomized benchmarking on each spin by itself and also on both spins simultaneously, to probe cross-talk effects. Furthermore, we developed and experimentally verified a new method called character randomized benchmarking [2,3], which combines the advantages of simultaneous and interleaved randomized benchmarking. With this new method, we characterized the fidelity of a C-Phase gate with tighter bounds than those in the traditional approach.

[1] T.F.Watson, et al, Nature 555, 633-637 (2018).
[2] J.Helsen, et al, arxiv:1806.02048.
[3] X.Xue, et al, manuscript in preparation.

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Presenters

  • Xiao Xue

    QuTech & Kavli Institute of Nanoscience, Delft University of Technology

Authors

  • Xiao Xue

    QuTech & Kavli Institute of Nanoscience, Delft University of Technology

  • Thomas F Watson

    QuTech and Kavli Institute of Nanoscience, Delft University of Technology, QuTech & Kavli Institute of Nanoscience, Delft University of Technology

  • Jonas Helsen

    QuTech, Delft University of Technology, Delft University of Technology

  • Daniel Ward

    Sandia National Laboratories, Sandia Natl Labs, University of Wisconsin-Madison

  • Donald E Savage

    University of Wisconsin-Madison, Department of Materials Science and Engineering, University of Wisconsin-Madison

  • Max G Lagally

    University of Wisconsin-Madison, University of Wisconsin, Department of Materials Science and Engineering, University of Wisconsin-Madison

  • Susan Coppersmith

    Department of Physics, University of Wisconsin-Madison, University of Wisconsin-Madison, University of Wisconsin - Madison

  • Mark Alan Eriksson

    Department of Physics, University of Wisconsin-Madison, University of Wisconsin-Madison, University of Wisconsin - Madison

  • Stephanie Wehner

    QuTech, Delft University of Technology, Delft University of Technology, Qutech, Delft University of Technology, TU Delft, Delft Univ of Tech, Delft University of Technology, QuTech

  • Lieven Vandersypen

    QuTech, TU Delft, QuTech and Kavli Institute of Nanoscience, Delft University of Technology, QuTech and Kavli Institute of NanoScience, TU Delft, Delft University of Technology, QuTech and Kavli Institute of Nanoscience, TU Delft, QuTech & Kavli Institute of Nanoscience, Delft University of Technology