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arXiv · 2102.05627

Comment on "Fluctuations in Extractable Work Bound the Charging Power of Quantum Batteries"

Stefano Cusumano·Łukasz Rudnicki
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Abstract

In the abstract of~[Phys. Rev. Lett. {\bf 125}, 040601 (2020)] one can read that: [...]{\it to have a nonzero rate of change of the extractable work, the state $ρ_\mathcal{W}$ of the battery cannot be an eigenstate of a "free energy operator", defined by $\mathcal{F}=H_\mathcal{W}+β^{-1}\log ρ_\mathcal{W}$, where $H_\mathcal{W}$ is the Hamiltonian of the battery and $β$ is the inverse temperature} [...]. Contrarily to what is presented below Eq.~(17) of the paper, we observe that the above conclusion does not hold when the battery is subject to nonunitary dynamics.

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Stefano Cusumano, Łukasz Rudnicki. 2021-02-10. Comment on "Fluctuations in Extractable Work Bound the Charging Power of Quantum Batteries". https://doi.org/10.1103/physrevlett.127.028901

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