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arXiv · 1912.07234

Quantum advantage in the charging process of Sachdev-Ye-Kitaev batteries

Davide Rossini·Gian Marcello Andolina·Dario Rosa·Matteo Carrega·Marco Polini
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Abstract

The exactly-solvable Sachdev-Ye-Kitaev (SYK) model has recently received considerable attention in both condensed matter and high energy physics because it describes quantum matter without quasiparticles, while being at the same time the holographic dual of a quantum black hole. In this Letter, we examine SYK-based charging protocols of quantum batteries with N quantum cells. Extensive numerical calculations based on exact diagonalization for N up to 16 strongly suggest that the optimal charging power of our SYK quantum batteries displays a super-extensive scaling with N that stems from genuine quantum mechanical effects. While the complexity of the nonequilibrium SYK problem involved in the charging dynamics prevents us from an analytical proof, we believe that this Letter offers the first (to the best of our knowledge) strong numerical evidence of a quantum advantage occurring due to the maximally-entangling underlying quantum dynamics.

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Davide Rossini, Gian Marcello Andolina, Dario Rosa, Matteo Carrega, Marco Polini. 2019-12-16. Quantum advantage in the charging process of Sachdev-Ye-Kitaev batteries. https://doi.org/10.1103/physrevlett.125.236402

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