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arXiv · 2401.04270

Observing the quantum Mpemba effect in quantum simulations

Lata Kh Joshi·Johannes Franke·Aniket Rath·Filiberto Ares·Sara Murciano·Florian Kranzl·Rainer Blatt·Peter Zoller·Benoît Vermersch·Pasquale Calabrese·Christian F. Roos·Manoj K. Joshi
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Abstract

The non-equilibrium physics of many-body quantum systems harbors various unconventional phenomena. In this study, we experimentally investigate one of the most puzzling of these phenomena -- the quantum Mpemba effect, where a tilted ferromagnet restores its symmetry more rapidly when it is farther from the symmetric state compared to when it is closer. We present the first experimental evidence of the occurrence of this effect in a trapped-ion quantum simulator. The symmetry breaking and restoration are monitored through entanglement asymmetry, probed via randomized measurements, and postprocessed using the classical shadows technique. Our findings are further substantiated by measuring the Frobenius distance between the experimental state and the stationary thermal symmetric theoretical state, offering direct evidence of subsystem thermalization.

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Lata Kh Joshi, Johannes Franke, Aniket Rath, Filiberto Ares, Sara Murciano, Florian Kranzl, Rainer Blatt, Peter Zoller, Benoît Vermersch, Pasquale Calabrese, Christian F. Roos, Manoj K. Joshi. 2024-01-08. Observing the quantum Mpemba effect in quantum simulations. https://arxiv.org/abs/2401.04270

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