Letter

Observation of a many-body dynamical phase transition with a 53-qubit quantum simulator

Received:
Accepted:
Published online:

Abstract

A quantum simulator is a type of quantum computer that controls the interactions between quantum bits (or qubits) in a way that can be mapped to certain quantum many-body problems1,2. As it becomes possible to exert more control over larger numbers of qubits, such simulators will be able to tackle a wider range of problems, such as materials design and molecular modelling, with the ultimate limit being a universal quantum computer that can solve general classes of hard problems3. Here we use a quantum simulator composed of up to 53 qubits to study non-equilibrium dynamics in the transverse-field Ising model with long-range interactions. We observe a dynamical phase transition after a sudden change of the Hamiltonian, in a regime in which conventional statistical mechanics does not apply4. The qubits are represented by the spins of trapped ions, which can be prepared in various initial pure states. We apply a global long-range Ising interaction with controllable strength and range, and measure each individual qubit with an efficiency of nearly 99 per cent. Such high efficiency means that arbitrary many-body correlations between qubits can be measured in a single shot, enabling the dynamical phase transition to be probed directly and revealing computationally intractable features that rely on the long-range interactions and high connectivity between qubits.

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Acknowledgements

We acknowledge discussions with M. Cetina, L. Duan, A. Polkovnikov, M. Heyl, M. Maghrebi, P. Titum and J. Iosue. This work is supported by the ARO and AFOSR Atomic and Molecular Physics Programs, the AFOSR MURI on Quantum Measurement and Verification, the IARPA LogiQ programme, the ARO MURI on Modular Quantum Systems, the ARL Center for Distributed Quantum Information, the NSF Quantum Information Science programme, and the NSF Physics Frontier Center at JQI. G.P. is supported by the IC Postdoctoral Research Fellowship Program.

Author information

Author notes

    • Z.-X. Gong

    Present address: Department of Physics, Colorado School of Mines, Golden, Colorado 80401, USA.

Affiliations

  1. Joint Quantum Institute and Joint Center for Quantum Information and Computer Science, University of Maryland Department of Physics and National Institute of Standards and Technology, College Park, Maryland 20742, USA.

    • J. Zhang
    • , G. Pagano
    • , P. W. Hess
    • , A. Kyprianidis
    • , P. Becker
    • , H. Kaplan
    • , A. V. Gorshkov
    • , Z.-X. Gong
    •  & C. Monroe
  2. IonQ, Inc., College Park, Maryland 20740, USA.

    • C. Monroe

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Contributions

J.Z., G.P., P.W.H., A.K., P.B., H.K. and C.M. all contributed to experimental design, construction, data collection and analysis. Z.-X.G. and A.V.G. contributed to the theory for the experiment. All authors contributed to this manuscript.

Competing interests

C.M. is a founding scientist of ionQ, Inc.

Corresponding author

Correspondence to J. Zhang.

Reviewer Information Nature thanks C. Muschik and C. Roos for their contribution to the peer review of this work.

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