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)

*Army Research Office (ARO) under grant numbers W911NF-17-1-0274 and W911NF-12-1-0607. Growth facilities used for fabricating samples is supported by DOE (DEFG02-03ER46028). Facilities supported by NSF through the University of Wisconsin-Madison MRSEC (DMR-1121288).

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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