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arXiv · 2208.04831

Fast charging of Lipkin-Meshkov-Glick quantum battery

Abstract

Fast charging is a pivotal and fundamental performance metric in quantum battery (QB) research. Here, we investigate the fast-charging performance of the Lipkin-Meshkov-Glick QB based on shortcuts to adiabaticity (STA). We mainly consider a scenario where the coupling strength between arbitrary two sites in the QB varies sinusoidally over time. We demonstrate that the STA protocol can remarkably enhance the charging efficiency. During the charging cycle, STA drives the periodic evolution of stored energy, coherence relative entropy, and energy fluctuations, and effectively suppresses energy fluctuation magnitude. We reveal that quantum coherence serves as a crucial quantum resource for boosting the charging efficiency of a QB. We analyze the influences of the anisotropy parameter, driving field amplitude and frequency, as well as particle number on the overall battery performance and show that an efficient charging and prominent charging advantages can be realized by modulating of these physical parameters. We further evaluate the energy cost throughout the charging process, and confirm that the maximum energy cost per particle can be reduced via appropriate tuning of driving field parameters. Our results offer valuable insights into the optimal design and practical implementation of high-efficiency fast-charging QB.

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Cheng-Jie Wang, Yuan-Jin Wang, Fu-Quan Dou. 2022-08-09. Fast charging of Lipkin-Meshkov-Glick quantum battery. https://doi.org/10.1002/qute.70405

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