Rapid single-shot detection of coherent tunneling in an InAs nanowire double quantum dot through dispersive gate sensing

ORAL

Abstract

Dispersive gate sensing can enable scalable and high-fidelity readout of solid-state quantum bits. In particular, it has been proposed for fast non-demolition readout of topological qubits that can be measured by single electrons tunneling through zero-energy modes [1, 2]. Such a readout requires resolving the coherent charge tunneling amplitude from a quantum dot in a Majorana zero-mode host system faithfully on short time scales.
Here we demonstrate rapid detection of single-electron tunneling between InAs nanowire quantum dots. To this end we have engineered a sensitive dispersive detection circuit by connecting a microwave resonator to a high-lever arm gate. This circuit translates charge tunneling between the dots into a dispersive shift on the resonator [3]. At charge degeneracy the phase shift of a reflected probe signal approaches its maximal possible value of 180 degrees, enabled by the large dot-resonator coupling. This allows us to detect the charge tunneling amplitude with an SNR exceeding two in a microsecond [4]. Our result paves the way for fast high-fidelity measurements of fermion parity in topological qubits.

[1] Plugge et al., NJP 19, 012001 (2017)
[2] Karzig et al., PRB 95, 235305 (2017)
[3] Blais et al., PRA 69, 062320 (2004)
[4] De Jong et al., in prep.

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Presenters

  • Damaz De Jong

    Delft University of Technology

Authors

  • Damaz De Jong

    Delft University of Technology

  • Jasper Van Veen

    QuTech and Kavli Institute of NanoScience, Delft University of Technology, Delft University of Technology, QuTech, Delft University of Technology

  • Luca Binci

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

  • Amrita Singh

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

  • Jesper Nygård

    Niels Bohr Institute, Center for Quantum Devices, Center for Quantum Devices and Station-Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices, Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, Niels Bohr Institute

  • Peter Krogstrup

    Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices and Station Q Copenhagen, University of Copenhagen, Center for Quantum Devices, Center for Quantum Devices, Station Q Copenhagen, Niels Bohr Institute, University of Copenhagen, Center for Quantum Devices and Microsoft Quantum Lab Copenhagen, Niels Bohr Institute, University of Copenhagen

  • Leo P Kouwenhoven

    Microsoft Station Q at Delft University of Technology, Microsoft Quantum Delft, Qutech, Delft University of Technology, QuTech, Delft University of Technology, Station Q Delft, Microsoft, Microsoft Station Q Delft, Microsoft Station-Q at Delft University of Technology, Microsoft Station Q Delft, Delft University of Technology

  • Wolfgang Pfaff

    Microsoft Station-Q at Delft University of Technology, Microsoft Station Q Delft, Delft University of Technology, Microsoft

  • John Watson

    Microsoft Quantum Delft, Microsoft Station-Q at Delft University of Technology, Microsoft Station Q Delft, Delft University of Technology