Parametric Coupling of Three Transmons for Multi-Qubit Interactions

ORAL

Abstract

Superconducting qubit architectures have largely converged on pairwise nearest-neighbor coupling mediated by capacitive couplers. While effective for scalable layouts, such localized connectivity introduces circuit decomposition overhead, requiring numerous SWAP operations and limiting the available entangling operations to two-qubit gates. Multi-qubit (N > 2) gates, by contrast, are useful resources for quantum algorithms, simulation, and error correction.

We present experimental progress on a system of three superconducting transmon qubits galvanically coupled through a common tunable SQUID element. This architecture enables all-to-all connectivity with high on/off coupling ratios, supporting fast, parametrically driven two- and three-qubit gates as well as tunable dispersive interactions that can suppress residual pairwise ZZ couplings. We will report recent experimental results demonstrating these capabilities.

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Presenters

  • Zachary Parrott

    • University of Colorado Boulder, National Institute of Standards and Technology
    • National Institute of Standards and Technology, Boulder, Colorado 80305, USA
    • University of Colorado, Boulder
    • University of Colorado Boulder
    • University of Colorado Boulder, National Institute of Standards and Technology Boulder
    • NIST, Boulder

Authors

  • Zachary Parrott

    • University of Colorado Boulder, National Institute of Standards and Technology
    • National Institute of Standards and Technology, Boulder, Colorado 80305, USA
    • University of Colorado, Boulder
    • University of Colorado Boulder
    • University of Colorado Boulder, National Institute of Standards and Technology Boulder
    • NIST, Boulder

  • Trevyn F.Q. F Larson

    • National Institute of Standards and Technology Boulder
    • National Institute of Standards and Technology
    • University of Colorado
    • University of Colorado Boulder, National Institute of Standards and Technology
    • University of Colorado Boulder, National Institute of Standards and Technology Boulder

  • Akash V Dixit

    • National Institute of Standards and Technology Boulder
    • National Institute of Standards and Technology

  • Sudhir Sahu

    • University of Colorado Boulder, National Institute of Standards and Technology, Department of Physics and Applied Physics, University of Massachusetts Lowell
    • University of Colorado Boulder, National Institute of Standards and Technology
    • National Institute of Standards and Technology

  • Kaixuan Ji

    • University of Colorado Boulder, National Institute of Standards and Technology
    • University of Colorado Boulder, National Institute of Standards and Technology Boulder

  • Tony McFadden

    • National Institute of Standards and Technology Boulder
    • National Institute of Standards and Technology
    • National Institute of Standards and Technology, Boulder CO 80305
    • National Institute of Standards and Technology, Boulder, Colorado 80305, USA
    • National Institute of Standards and Technology (NIST)
    • University of California, Santa Barbara
    • National Institute of Standards and Technology, Boulder

  • Ray W Simmonds

    • National Institute of Standards and Technology, University of Colorado Boulder
    • National Institute of Standards and Technology
    • National Institute of Standards and Technology Boulder
    • The Global Coherence Project