ABSTRACT Fast charging is a pivotal and fundamental performance metric in quantum battery (QB) research. Here, we investigate the fast‐charging performance of the Lipkin–Meshkov–Glick QB based on shortcuts to adiabaticity (STA). We mainly consider a scenario where the coupling strength between arbitrary two sites in the QB varies sinusoidally over time. We demonstrate that the STA protocol can remarkably enhance the charging efficiency. During the charging cycle, STA drives the periodic evolution of stored energy, coherence relative entropy, and energy fluctuations, and effectively suppresses energy fluctuation magnitude. We reveal that quantum coherence serves as a crucial quantum resource for boosting the charging efficiency of a QB. We analyze the influences of the anisotropy parameter, driving field amplitude and frequency, as well as particle number on the overall battery performance and show that efficient charging and prominent charging advantages can be realized by modulating these physical parameters. We further evaluate the energy cost throughout the charging process, and confirm that the maximum energy cost per particle can be reduced via appropriate tuning of driving field parameters. Our results offer valuable insights into the optimal design and practical implementation of high‐efficiency fast‐charging QB.
ABSTRACT Fast charging is a pivotal and fundamental performance metric in quantum battery (QB) research. Here, we investigate the fast‐charging performance of the Lipkin–Meshkov–Glick QB based on shortcuts to adiabaticity (STA). We mainly consider a scenario where the coupling strength between arbitrary two sites in the QB varies sinusoidally over time. We demonstrate that the STA protocol can remarkably enhance the charging efficiency. During the charging cycle, STA drives the periodic evolution of stored energy, coherence relative entropy, and energy fluctuations, and effectively suppresses energy fluctuation magnitude. We reveal that quantum coherence serves as a crucial quantum resource for boosting the charging efficiency of a QB. We analyze the influences of the anisotropy parameter, driving field amplitude and frequency, as well as particle number on the overall battery performance and show that efficient charging and prominent charging advantages can be realized by modulating these physical parameters. We further evaluate the energy cost throughout the charging process, and confirm that the maximum energy cost per particle can be reduced via appropriate tuning of driving field parameters. Our results offer valuable insights into the optimal design and practical implementation of high‐efficiency fast‐charging QB.
We explore the operation of quantum batteries in the Lipkin-Meshkov-Glick (LMG) model, when they are charged either through a sudden quench in the magnetic field strength or by coupling them to a single-mode bosonic charger. Through initializing the battery in either the symmetric or broken symmetry phases of the LMG model we analyze how the different spectral properties can affect the performance of both the charging and discharging of the battery. In particular, we show that by quenching the magnetic field strength from the symmetric phase to the broken phase, we can achieve a significant enhancement in stored energy, as well as stable and efficient ergotropy extraction. Similar observations can be made when introducing weak coupling between the battery with the bosonic charger, while the amount of stored work and ergotropy saturate at strong coupling. These findings emphasize the importance of the magnetic field dynamics or environmental coupling in optimizing charging performance, which could lead to practical applications in quantum energy storage.
ABSTRACT Nowadays, quantum batteries (QBs) have been designed to outperform their classical counterparts by leveraging quantum advantages. For instance, the charging power greatly benefits from global charging protocols (e.g., the Dicke QB), especially in the ultrastrong coupling regime or even larger. However, apart from the fragility of QB under intrinsic decoherence, another critical drawback emerges inevitably. Specifically, the non‐negligible counter‐rotating term in the ultrastrong regime would induce coherence in the energy basis of QB, thus remarkably degrading the charging efficiency. To tackle these challenges, we propose a high‐efficiency and noise‐immune QB boosted by dynamical modulation. It is demonstrated that the modulation can effectively reduce the counter‐rotating coupling, resulting in a notable improvement in charging efficiency. Particularly, for a judicious choice of modulation parameters, the QB can be charged optimally. In the subsequent storage process, beyond the natural robustness to pure dephasing noise, our scenario is also highly resilient to the dissipation noise and thus can achieve perfect energy storage by effective bath engineering. While feasible with current experimental platforms, our proposal offers a solid foundation for the implementation of a powerful QB and may drastically promote the development of energy storage and delivery techniques in the future.
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_{f}^{opt} 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_{f}^{opt} and the corresponding thermal state by using the one-norm distance.
An open quantum battery (QB) model of a single qubit system charging in a coherent auxiliary bath (CAB) consisting of a series of independent coherent ancillae is considered. According to the collision charging protocol we derive a quantum master equation and obtain the analytical solution of QB in a steady state. We find that the full charging capacity (or the maximal extractable work (MEW)) of QB, in the weak QB-ancilla coupling limit, is positively correlated with the coherence magnitude of ancilla. Combining with the numerical simulations we compare with the charging properties of QB at finite coupling strength, such as the MEW, average charging power and the charging efficiency, when considering the bath to be a thermal auxiliary bath (TAB) and a CAB, respectively. We find that when the QB with CAB, in the weak coupling regime, is in fully charging, both its capacity and charging efficiency can go beyond its classical counterpart, and they increase with the increase of coherence magnitude of ancilla. In addition, the MEW of QB in the regime of relative strong coupling and strong coherent magnitude shows the oscillatory behavior with the charging time increasing, and the first peak value can even be larger than the full charging MEW of QB. This also leads to a much larger average charging power than that of QB with TAB in a short-time charging process. These features suggest that with the help of quantum coherence of CAB it becomes feasible to switch the charging schemes between the long-time slow charging protocol with large capacity and high efficiency and the short-time rapid charging protocol with highly charging power only by adjusting the coupling strength of QB-ancilla. This work clearly demonstrates that the quantum coherence of bath can not only serve as the role of “fuel” of QB to be utilized to improve the QB’s charging performance but also provide an alternative way to integrate the different charging protocols into a single QB.
Although implementing shortcuts to adiabaticity (STA) in open quantum systems remains challenging due to the complex control schemes required for such systems, their powerful ability to rapidly steer the system toward target states and their widespread applicability in quantum technologies have motivated us to explore their potential in quantum energy storage. In this work, we employ STA techniques to charge an open quantum battery and demonstrate that the extractable work (Ergotropy) from such a battery can be significantly enhanced by several times compared to the case where the battery is charged using a time independent driving field. Our results pave the way for accelerating the dynamics of open quantum systems and suggest promising applications in the development of high-performance, stable quantum batteries.
Quantum batteries are energy storage devices that satisfy quantum mechanical principles. How to improve the battery’s performance such as stored energy and power is a crucial element in the quantum battery. Here, we investigate the charging and discharging dynamics of a three-level counterdiabatic stimulated Raman adiabatic passage quantum battery via shortcuts to adiabaticity, which can compensate for undesired transitions to realize a fast adiabatic evolution through the application of an additional control field to an initial Hamiltonian. The scheme can significantly speed up the charging and discharging processes of a three-level quantum battery and obtain more stored energy and higher power compared with the original stimulated Raman adiabatic passage. We explore the effect of both the amplitude and the delay time of driving fields on the performances of the quantum battery. Possible experimental implementation in superconducting circuit and nitrogen-vacancy center is also discussed.