Noise correlations in a two-qubit Si/SiGe quantum dot device

ORAL

Abstract

Qubits are affected by noise in their environment, but conversely can also be used to probe this noise and study properties such as spectral density and correlations. We use a two-qubit device in a Si/SiGe hetrostructure [1] to investigate noise correlations by studying the decay of two Bell states. These Bell states are insensitive to either correlated or anti-correlated noise, resembling the concept of decoherence-free subspaces, which allows us to extract the uncorrelated, correlated and anti-correlated contributions to the noise affecting the qubits from the decay times for the different initial states. Knowledge about the noise properties makes it possible to design operations that are less sensitive to this noise, and yields information on the noise source, which potentially makes it possible to reduce the noise. We demonstrate this method by artificially adding (anti-) correlated noise and use it characterize the noise in our system.

[1] T.F. Watson et al., Nature 555, 633 (2018)

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Presenters

  • Jelmer Boter

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

Authors

  • Jelmer Boter

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

  • Xiao Xue

    Delft University of Technology, QuTech and 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

  • Tobias Krähenmann

    QuTech and Kavli Institute of Nanoscience, Delft University of Technology

  • Vickram Premakumar

    University of Wisconsin-Madison, University of Wisconsin - Madison

  • 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

  • Mark G Friesen

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

  • Robert James Joynt

    University of Wisconsin-Madison, University of Wisconsin - Madison

  • 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