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arXiv · 2211.01275

Continuous Symmetry Breaking in a Trapped-Ion Spin Chain

Lei Feng·Or Katz·Casey Haack·Mohammad Maghrebi·Alexey V. Gorshkov·Zhexuan Gong·Marko Cetina·Christopher Monroe
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Abstract

One-dimensional systems exhibiting a continuous symmetry can host quantum phases of matter with true long-range order only in the presence of sufficiently long-range interactions. In most physical systems, however, the interactions are short-ranged, hindering the emergence of such phases in one dimension. Here we use a one-dimensional trapped-ion quantum simulator to prepare states with long-range spin order that extends over the system size of up to $23$ spins and is characteristic of the continuous symmetry-breaking phase of matter. Our preparation relies on simultaneous control over an array of tightly focused individual-addressing laser beams, generating long-range spin-spin interactions. We also observe a disordered phase with frustrated correlations. We further study the phases at different ranges of interaction and the out-of-equilibrium response to symmetry-breaking perturbations. This work opens an avenue to study new quantum phases and out-of-equilibrium dynamics in low-dimensional systems.

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Lei Feng, Or Katz, Casey Haack, Mohammad Maghrebi, Alexey V. Gorshkov, Zhexuan Gong, Marko Cetina, Christopher Monroe. 2022-11-02. Continuous Symmetry Breaking in a Trapped-Ion Spin Chain. https://doi.org/10.1038/s41586-023-06656-7

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