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Abstract
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Recent theoretical and experimental protocols for the stable and effective charging of open quantum batteries
(QBs), in particular adiabatic charging of three-level QBs via stimulated Raman adiabatic passages, have
sparked renewed interest in adiabatic quantum dynamics. A central question is whether exploiting the adiabatic
master equation could provide advantages over the previous studies in the effective charging of open QBs.
To answer this question, we revisit the adiabatic charging of three-level QB by using the adiabatic quantum
master equation formalism. We restrict ourselves to the weak-coupling regime with an Ohmic thermal bath and
investigate the effects of relaxation and dephasing on the charging process. It is also worth emphasizing that our
protocol to investigate the charging process of QBs based on the adiabatic master equation despite the previous
studies is not phenomenological and is general. We analyze the dependence of the stored energy, ergotropy, as
well as the efficiency of the QB on the total time of evolution t f . We demonstrate that for very short charging
time (t f ), where the evolution is highly nonadiabatic, the stored energy and ergotropy are very small. However,
by increasing t f we show that there is an optimal charging time t opt f in which, at low temperatures, we could fully
charge the battery and effectively extract the entire amount of energy from it. Note that the optimal charging
time could be decreased by adjusting the strength of the coupling between the system and environment and
also be the appropriate choice of the Hamiltonian parameters, which, in turn, speed up the charging process.
However, we show that for very long charging time t f the charging energy, ergotropy, and efficiency decrease
due to thermal excitations. Furthermore, to obtain more insights about the problem we investigate the distance
between the density matrix of a system at optimal charging time t opt f and the corresponding thermal state by using
the o
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