Fast dispersive readout of superconducting qubits for fault-tolerant quantum computing

ORAL

Abstract

Fault-tolerant quantum computing requires repetitive high-fidelity quantum parity measurements. In quantum processors based on circuit QED, the fidelity of indirect quantum parity measurements using an ancillary qubit is compromised by errors induced in the coherent interaction step and in the ancilla measurement. Here, we improve upon the state of the art by combining two techniques to reduce ancilla measurement time and measurement-induced cross-dephasing of data qubits: dedicated Purcell filtering for each qubit and active photon depletion. We find the parity measurement speed limit by minimizing the parity measurement error rate as a function of the cycle time. We individually quantify the error contributions of one- and two-qubit gates, residual interactions, cross-talk, parasitic measurement-induced dephasing, and quantum demolition.

*This research is funded by IARPA (U.S. Army Research Office Grant W911NF-16-1-0071). Additional funding is provided by Intel Corporation (N.M.).

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Presenters

  • Cornelis Christiaan Bultink

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands

Authors

  • Cornelis Christiaan Bultink

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands

  • Rene Vollmer

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands

  • Nandini Muthusubramanian

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
    • QuTech and Kavli Institute of Nanoscience Delft, Delft University of Technology

  • Marc Beekman

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands

  • Michiel Adriaan Rol

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands

  • Brian M Tarasinski

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
    • QuTech and Kavli Institute of Nanoscience Delft, Delft University of Technology

  • Leonardo DiCarlo

    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology
    • QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands
    • QuTech and Kavli Institute of Nanoscience Delft, Delft University of Technology