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arXiv · 2502.07513

Entanglement and energy transportation in the central-spin quantum battery

Fan Liu·Hui-Yu Yang·Shuai-Li Wang·Jun-Zhong Wang·Kun Zhang·Xiao-Hui Wang
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Abstract

Quantum battery exploits the principle of quantum mechanics to transport and store energy. We study the energy transportation of the central-spin quantum battery, which is composed of $N_b$ spins serving as the battery cells, and surrounded by $N_c$ spins serving as the charger cells. We apply the invariant subspace method to solve the dynamics of the central-spin battery with a large number of spins. We establish a universal inverse relationship between the battery capacity and the battery-charger entanglement, which persists in any size of the battery and charger cells. Moreover, we find that when $N_b=N_c$, the central-spin battery has the optimal energy transportation, corresponding to the minimal battery-charger entanglement. Surprisingly, the central-spin battery has a uniform energy transportation behaviors in certain battery-charger scales. Our results reveal a nonmonotonic relationship between the battery-charger size and the energy transportation efficiency, which may provide more insights on designing other types of quantum batteries.

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Fan Liu, Hui-Yu Yang, Shuai-Li Wang, Jun-Zhong Wang, Kun Zhang, Xiao-Hui Wang. 2025-02-11. Entanglement and energy transportation in the central-spin quantum battery. https://doi.org/10.1088/1674-1056/ad9a9d

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