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arXiv · 2012.06187

Quantum battery of interacting spins with environmental noise

Fang Zhao·Fu-Quan Dou·Qing Zhao
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Abstract

A quantum battery is a temporary energy-storage system. We constructed the quantum battery model of an N-spin chain with nearest-neighbor hopping interaction and investigated the charging process of the quantum battery. We obtained the maximum energy in the quantum battery charged by a coherent cavity driving field or a thermal heat bath. We confirmed that for a finite-length spin chain, thermal charging results in a nonzero ergotropy, contradicting a previous result: that an incoherent heat source cannot charge a single-spin quantum battery. The nearest-neighbor hopping interaction induces energy band splitting, which enhances the energy storage and the ergotropy of the quantum battery. We found a critical point in the energy and ergotropy resulting from the ground-state quantum phase transition, after which the energy significantly enhance. Finally, we also found that disorder increased the energy of the quantum battery.

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Fang Zhao, Fu-Quan Dou, Qing Zhao. 2020-12-11. Quantum battery of interacting spins with environmental noise. https://doi.org/10.1103/physreva.103.033715

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