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arXiv · 2303.04977

Quantum Ergotropy and Quantum Feedback Control

Kenta Koshihara·Kazuya Yuasa
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Abstract

We study the energy extraction from and charging to a finite-dimensional quantum system by general quantum operations. We prove that the changes in energy induced by unital quantum operations are limited by the ergotropy/charging bound for unitary quantum operations. This implies that, in order to break the ergotropy/charging bound for unitary quantum operations, one needs to perform a quantum operation with feedback control. We also show that the ergotropy/charging bound for unital quantum operations, applied to initial thermal equilibrium states, is tighter than the inequality representing the standard second law of thermodynamics without feedback control.

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Kenta Koshihara, Kazuya Yuasa. 2023-03-09. Quantum Ergotropy and Quantum Feedback Control. https://doi.org/10.1103/physreve.107.064109

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