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arXiv · 2105.08282

Signatures of quantum chaos in an out-of-time-order tensor

Magdalini Zonnios·Jesper Levinsen·Meera M. Parish·Felix A. Pollock·Kavan Modi
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Abstract

Motivated by the famous ink-drop experiment, where ink droplets are used to determine the chaoticity of a fluid, we propose an experimentally implementable method for measuring the scrambling capacity of quantum processes. Here, a system of interest interacts with a small quantum probe whose dynamical properties identify the chaoticity of the system. Specifically, we propose a fully quantum version of the out-of-time-order correlator (OTOC) - which we term the out-of-time-order matrix (OTOM) - whose correlations offer clear information theoretic meanings about the chaoticity of a process. We illustrate the utility of the OTOM as a signature of chaos using random unitary processes as well as in the quantum kicked rotor, where the chaoticity is tuneable.

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Magdalini Zonnios, Jesper Levinsen, Meera M. Parish, Felix A. Pollock, Kavan Modi. 2021-05-18. Signatures of quantum chaos in an out-of-time-order tensor. https://doi.org/10.1103/physrevlett.128.150601

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