We propose and analyze a hybrid qubit-qutrit quantum battery (QB) based on a mixed spin-1/2 and spin-1 system interacting via an anisotropic Heisenberg exchange coupling in the presence of a homogeneous magnetic field. The nonclassical properties of the system are characterized using the l1-norm of coherence and negativity, which quantify quantum coherence and entanglement, respectively. The performance of the quantum battery is evaluated through key indicators such as ergotropy, power, and capacity. Our results reveal that both ergotropy and power exhibit oscillatory dynamics, while the capacity remains constant over time. We further investigate the influence of system parameters and magnetic field strength on both quantum correlations and battery performance, demonstrating that nonclassicality plays a crucial role in enhancing energy-storage efficiency. Importantly, we establish a connection between the theoretical model and an experimentally realizable nickel-radical molecular complex, showing that quantum coherence, entanglement, and efficient energy storage persist even at room temperature. These findings provide a realistic pathway toward the implementation of hybrid qubit-qutrit quantum batteries in solid-state molecular platforms.
We propose and analyze a hybrid qubit-qutrit quantum battery (QB) based on a mixed spin-1/2 and spin-1 system interacting via an anisotropic Heisenberg exchange coupling in the presence of a homogeneous magnetic field. The nonclassical properties of the system are characterized using the l1-norm of coherence and negativity, which quantify quantum coherence and entanglement, respectively. The performance of the quantum battery is evaluated through key indicators such as ergotropy, power, and capacity. Our results reveal that both ergotropy and power exhibit oscillatory dynamics, while the capacity remains constant over time. We further investigate the influence of system parameters and magnetic field strength on both quantum correlations and battery performance, demonstrating that nonclassicality plays a crucial role in enhancing energy-storage efficiency. Importantly, we establish a connection between the theoretical model and an experimentally realizable nickel-radical molecular complex, showing that quantum coherence, entanglement, and efficient energy storage persist even at room temperature. These findings provide a realistic pathway toward the implementation of hybrid qubit-qutrit quantum batteries in solid-state molecular platforms.
This study explores the energy storage dynamics of a quantum battery (QB) modeled using a dipolar spin system with Dzyaloshinskii-Moriya (DM) interaction. We examine the performance of this system in terms of ergotropy, instantaneous power, capacity, and quantum coherence using a two-qubit model. By solving the system's time evolution under cyclic unitary processes, we analyze how external parameters such as temperature, magnetic field, and DM interaction influence the charging behavior and quantum resources of the battery. The findings demonstrate that quantum coherence and DM interaction significantly enhance the energy storage efficiency and power output of the quantum battery, offering promising strategies for designing high-performance quantum energy storage devices. Furthermore, we investigate the performance of quantum battery under the influence of a common dephasing environment, which limits the long-term work-extraction capability of dipolar quantum batteries.
Abstract This study explores the energy storage dynamics of a quantum battery (QB) modeled using a dipolar spin system with Dzyaloshinskii–Moriya (DM) interaction. We examine the performance of this system in terms of ergotropy, instantaneous power, capacity, and quantum coherence using a two-qubit model. By solving the system’s time evolution under cyclic unitary processes, we analyze how external parameters such as temperature, magnetic field, and DM interaction influence the charging behavior and quantum resources of the battery. The findings demonstrate that quantum coherence and DM interaction significantly enhance the energy storage efficiency and power output of the quantum battery, offering promising strategies for designing high-performance quantum energy storage devices. Furthermore, we investigate the performance of quantum battery under the influence of a common dephasing environment, which limits the long-term work-extraction capability of dipolar quantum batteries.
Abstract Quantum batteries (QBs) have been proposed as devices that exploit the advantage of quantum resources, such as coherence and entanglement, to improve charging performance. In this study, we theoretically investigate a QB model based on two coupled double quantum dots (TDQDs) implemented on the well-established AlGaAs/GaAs platform for quantum nanodevice fabrication. Using ergotropy and power as key performance indicators, we examine how various system parameters affect the energy performance of the QB. Our study begins with an analysis of quantum resources in the QB’s initial state, followed by an examination of how control parameters that influence these resources impact the modeling and performance of the battery. Our results demonstrate that increasing the energy offset improves ergotropy and power but reduces quantum correlations. Conversely, increasing tunneling couplings leads to a non-monotonic variation in the maximum ergotropy, which peaks at a certain point before decreasing, closely following the behavior of quantum entanglement despite continued growth in quantum coherence. This highlights the feasibility of efficient energy storage in quantum dots (QDs) for use in quantum batteries (QBs). It also emphasizes that coherence alone is insufficient for optimal performance and that other quantum correlations are necessary and must be carefully considered to fully exploit the potential of quantum resources.
This study investigates the dynamical behaviour of a two-cell (two-atom) quantum battery driven by a two-mode charging field. We explore the influence of varying interaction strengths on the system?s performance. This includes increasing the coupling between cells and charging fields, and cells themselves through a dipole interaction and Ising interaction along the z-axis. Additionally, the impact of environmental effects is examined by incorporating decay terms for both the charging fields and the cells. Our analysis focuses on key performance metrics such as stored energy, average power, ergotropy, energy fluctuations, and quantum speed limit time. The results reveal that the environment negatively impacts stored energy, power, and ergotropy, but leads to higher speed limits. Enhanced coupling between the charging fields and the cells improves the studied correlations, promoting efficient energy transfer and decreasing speed limit time. Increasing the coupling between the cells, either via the dipole or Ising interaction, generally exhibits a similar effect. This involves a decrease in maximum achievable energy storage, accompanied by the emergence of more erratic energy fluctuations.
With intensive studies of quantum thermodynamics, quantum batteries (QBs) have been proposed to store and transfer energy via quantum effects. Despite many theoretical models, decoherence remains a severe challenge and practical platforms are still rare. Here, we propose a QB based on the coherent Ising machine, in which the signal field acts as the core energy-storage unit. To clarify the role of quantum coherence in resisting dissipation, we decompose the ergotropy, i.e., the maximum extractable work from the QB, into its coherent and incoherent components. We find that the coherent part decays at a rate roughly half that of the incoherent part, exhibiting much stronger robustness against decoherence. More importantly, the coherent ergotropy and the average charging power reach their respective maxima at essentially the same moment, which defines the optimal instant to switch off the pump field. Finally, by coupling the QB to a two-level system as the load, we demonstrate an efficient energy discharge process of the proposed QB. Our work establishes a realistic and immediately-implementable QB architecture on a mature optical platform, laying a foundation for experimental exploration of quantum energy storage.
This study examines the performance of finite spin quantum batteries (QBs) using Heisenberg XX,XY,XXZ, and XYZ spin models with Dzyaloshinsky-Moriya (DM) and Kaplan--Shekhtman--Entin-Wohlman--Aharony (KSEA) interactions. The QBs are modeled as interacting quantum spins in local inhomogeneous magnetic fields, inducing variable Zeeman splitting. We derive analytical expressions for the maximal extractable work, ergotropy and the capacity of QBs, as recently examined by Yang et al. [Phys. Rev. Lett. 131, 030402 (2023)]. These quantities are analytically linked through certain quantum correlations, as posited in the aforementioned study. Different Heisenberg spin-chain models exhibit distinct behaviors under varying conditions, emphasizing the importance of model selection for optimizing QB performance. In antiferromagnetic (AFM) systems, maximum ergotropy occurs with a Zeeman splitting field applied to either spin, while ferromagnetic (FM) systems benefit from a uniform Zeeman field. Temperature significantly impacts QB performance such that ergotropy in the AFM case is generally more robust against increasing temperature compared to the FM case. Incorporating DM and KSEA couplings can significantly enhance the capacity and ergotropy extraction of QBs. However, there exists a threshold beyond which additional increases in these interactions cause a sharp decline in capacity and ergotropy. This behavior is influenced by temperature and quantum coherence, which signal the occurrence of a sudden phase transition. The resource theory of quantum coherence proposed by Baumgratz et al. [Phys. Rev. Lett. 113, 140401 (2014)] plays a crucial role in enhancing ergotropy and capacity. However, ergotropy is limited by both the system's capacity and the amount of coherence. These findings support the theoretical framework of spin-based QBs and may benefit future research on quantum energy storage devices.