A tunable coupler for suppressing ZZ crosstalk and realizing multiform two qubit-gates

POSTER

Abstract


Controllable interaction between superconducting qubits is desirable for scalability architectures and quantum simulation applications. We experimentally demonstrate a simple-design tunable coupler, achieving a continuous tunability and almost zero coupling strength. Based on the tunable interaction between two qubits via the coupler, we first construct two-qubit iSWAP and control-Z(CZ) gate by applying standard rectangular pulses. We then propose a new ‘Dynamic-Total-Closing’(DTC) technology to implement the CZ gate, which adopts a graded flux pulse for the qubit to approach the avoided crossing slowly, meanwhile dynamically closing the qubit-qubit coupling with a special pulse shape during the approaching process(fidelity up to 98.4%). Furthermore, we also try iSWAP gate by parametrically oscillating coupler at the qubit-qubit detuning and cross-resonance gate by tuning coupler frequency to explore the influence of ZZ interaction.

Presenters

  • Zenghui Bao

    • Tsinghua University

Authors

  • Tianqi Cai

    • Institute for Interdisciplinary Information Sciences, Tsinghua University
    • Tsinghua University
  • Xiyue Han

    • Institute for Interdisciplinary Information Sciences, Tsinghua University
    • Tsinghua University
  • Zenghui Bao

    • Tsinghua University
  • Zhiling Wang

    • Institute for Interdisciplinary Information Sciences, Tsinghua University
    • Tsinghua University
  • Hongyi Zhang

    • Institute for Interdisciplinary Information Sciences, Tsinghua University
    • Tsinghua University
  • Yipu Song

    • Institute for Interdisciplinary Information Sciences, Tsinghua University
    • Tsinghua University
    • Center for Quantum Information, Institute for Interdisciplinary Information Sciences, Tsinghua University
  • Luming Duan

    • Center for Quantum Information , IIIS, Tsinghua University
    • Tsinghua University
    • Institute for Interdisciplinary Information Sciences, Tsinghua University
    • Center for Quantum Information, IIIS, Tsinghua University, Beijing 100084, P. R. China
    • Center for Quantum Information, IIIS, Tsinghua University
    • Center for Quantum Information, Tsinghua University