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arXiv · 1708.01044

Observation of a Many-Body Dynamical Phase Transition with a 53-Qubit Quantum Simulator

J. Zhang·G. Pagano·P. W. Hess·A. Kyprianidis·P. Becker·H. Kaplan·A. V. Gorshkov·Z. -X. Gong·C. Monroe
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Abstract

A quantum simulator is a restricted class of quantum computer that controls the interactions between quantum bits in a way that can be mapped to certain difficult quantum many-body problems. As more control is exerted over larger numbers of qubits, the simulator can tackle a wider range of problems, with the ultimate limit being a universal quantum computer that can solve general classes of hard problems. We use a quantum simulator composed of up to 53 qubits to study a non-equilibrium phase transition in the transverse field Ising model of magnetism, in a regime where conventional statistical mechanics does not apply. The qubits are represented by trapped ion spins that can be prepared in a variety of initial pure states. We apply a global long-range Ising interaction with controllable strength and range, and measure each individual qubit with near 99% efficiency. This allows the single-shot measurement of arbitrary many-body correlations for the direct probing of the dynamical phase transition and the uncovering of computationally intractable features that rely on the long-range interactions and high connectivity between the qubits.

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J. Zhang, G. Pagano, P. W. Hess, A. Kyprianidis, P. Becker, H. Kaplan, A. V. Gorshkov, Z. -X. Gong, C. Monroe. 2017-08-03. Observation of a Many-Body Dynamical Phase Transition with a 53-Qubit Quantum Simulator. https://doi.org/10.1038/nature24654

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