Physical Review X (Apr 2021)

Quantum Information Scrambling on a Superconducting Qutrit Processor

  • M. S. Blok,
  • V. V. Ramasesh,
  • T. Schuster,
  • K. O’Brien,
  • J. M. Kreikebaum,
  • D. Dahlen,
  • A. Morvan,
  • B. Yoshida,
  • N. Y. Yao,
  • I. Siddiqi

DOI
https://doi.org/10.1103/PhysRevX.11.021010
Journal volume & issue
Vol. 11, no. 2
p. 021010

Abstract

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The dynamics of quantum information in strongly interacting systems, known as quantum information scrambling, has recently become a common thread in our understanding of black holes, transport in exotic non-Fermi liquids, and many-body analogs of quantum chaos. To date, verified experimental implementations of scrambling have focused on systems composed of two-level qubits. Higher-dimensional quantum systems, however, may exhibit different scrambling modalities and are predicted to saturate conjectured speed limits on the rate of quantum information scrambling. We take the first steps toward accessing such phenomena, by realizing a quantum processor based on superconducting qutrits (three-level quantum systems). We demonstrate the implementation of universal two-qutrit scrambling operations and embed them in a five-qutrit quantum teleportation protocol. Measured teleportation fidelities F_{avg}=0.568±0.001 confirm the presence of scrambling even in the presence of experimental imperfections and decoherence. Our teleportation protocol, which connects to recent proposals for studying traversable wormholes in the laboratory, demonstrates how quantum technology that encodes information in higher-dimensional systems can exploit a larger and more connected state space to achieve the resource efficient encoding of complex quantum circuits.