Operating four singlet-triplet qubits in a two-dimensional array of GaAs dots

ORAL

Abstract

Building small-scale spin-based quantum processors requires the ability to perform simultaneous, fast measurements in single- and two-dimensional qubit arrays, as well as overcome challenges like gate crosstalk, tuning in large parameter spaces, and pulse calibration. Here we present the simultaneous coherent manipulation and readout of a two-by-two singlet-triplet qubit array in GaAs, with a large multielectron dot coupler at the center. Using four independent charge-sensors read out via a frequency-multiplexed RF-reflectometry setup, we show coherent exchange oscillations, concurrently monitor the Overhauser field at the four sites of the array, and interlace different pulse operations. Finally, we establish a coherent exchange coupling between one qubit and the central multi-electron dot coupler, suggesting its use as a mechanism to provide on-demand connectivity within the array.

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Presenters

  • Federico Fedele

    Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark.

Authors

  • Federico Fedele

    Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark.

  • Anasua Chatterjee

    Univ of Copenhagen, Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark.

  • Saeed Fallahi

    Physics and Astronomy, Purdue University, Purdue University, Department of Physics and Astronomy, Microsoft Quantum Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA, Physics, Purdue University

  • Geoff C Gardner

    Purdue University, Birck Nanotechnology Center and Microsoft Quantum Purdue, Purdue University, Department of Physics and Astronomy and Station Q Purdue, Purdue University, Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907, USA, Microsoft Quantum Purdue, Department of Physics and Astronomy, Microsoft Quantum Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA, Physics, Purdue University

  • Michael Manfra

    Physics and Astronomy, Purdue Univ, Department of Physics and Astronomy and Station Q Purdue, Birck Nanotechnology Center, School of Materials Engineering, School of Electrical and Computer Engineering, Purdue, Purdue Univ, Purdue University, Microsoft Quantum at Station Q Purdue, Department of Physics and Astronomy, Birck Nanotechnology Center, Microsoft Quantum Purdue, School og Materials Engineering & School of Electrical and Computer Engineering, P, Physics and Astronomy, Purdue University, Department of Physics and Astronomy and Station Q Purdue, Purdue University, Department of Physics and Astronomy and Microsoft Quantum Purdue, Purdue University, West Lafayette, Indiana 47907 USA, Department of Physics and Astronomy, PURDUE UNIVERSITY, Department of Physics and Astronomy, Microsoft Quantum Purdue, Birck Nanotechnology Center, Purdue University, West Lafayette, Indiana 47907, USA, Physics, Purdue University

  • Ferdinand Kuemmeth

    Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark.