Abstract A model for a quantum battery in an accelerated frame is proposed. The battery comprises a two-qubit system initialized in its ground state and is charged via a dipolar interaction Hamiltonian. The acceleration process requires the system to be described from the perspective of two distinct spacetime regions. We investigate the influence of the initial spin orientation, the spin-spin coupling parameter, and the acceleration rate on the battery’s performance, specifically its stored energy, charging power, and extractable work. Our results demonstrate that the battery’s energy oscillates between lower and upper bounds, allowing it to be charged at any finite acceleration. All three physical quantities decrease in the first region and increase in the second region as the acceleration rate rises. Furthermore, the values of these quantities in the second region are consistently smaller than their counterparts in the first region. The largest upper and lower bounds of these quantities occur for spins oriented in the xy -plane, while the smallest bounds are observed for spins polarized along the z -axis.
Abstract A model for a quantum battery in an accelerated frame is proposed. The battery comprises a two-qubit system initialized in its ground state and is charged via a dipolar interaction Hamiltonian. The acceleration process requires the system to be described from the perspective of two distinct spacetime regions. We investigate the influence of the initial spin orientation, the spin-spin coupling parameter, and the acceleration rate on the battery’s performance, specifically its stored energy, charging power, and extractable work. Our results demonstrate that the battery’s energy oscillates between lower and upper bounds, allowing it to be charged at any finite acceleration. All three physical quantities decrease in the first region and increase in the second region as the acceleration rate rises. Furthermore, the values of these quantities in the second region are consistently smaller than their counterparts in the first region. The largest upper and lower bounds of these quantities occur for spins oriented in the xy -plane, while the smallest bounds are observed for spins polarized along the z -axis.
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.
We discuss a one-dimensional coupled qubit-array quantum battery model under Born-Karman boundary conditions and investigate both the charging and discharging processes. Applying the stored energy, charging power, and ergotropy as the essential physical indicators of quantum battery, it is observed that minimizing the hopping interaction between the nearest-neighbor qubits in the qubit-array and increasing the number of qubits during battery setup are crucial. Additionally, we employ a classical driving field to optimize battery performance and explore the optimal quantum battery performance by adjusting the driving strength of the classical field. Finally, we have discovered that the initial energy in the charger no longer needs to be higher than the energy in the battery in our protocol, the charger will continue to supply energy to the battery even when there is limited initial available energy in the charger. And the conventional approach of preparing the battery's initial state in its ground state, as observed in previous studies, may not necessarily be the optimal choice. By introducing a strong classical driving field, it is possible to enhance energy storage by allowing for an initial presence of some energy within the battery.
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.
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.
Quantum batteries represent a new and promising technological application of quantum mechanics, offering the potential for enhanced energy storage and fast charging. In this work, we study a quantum battery composed of three two-level systems with XXZ coupling operating under open boundary conditions. We investigate the role played by ferromagnetic and antiferromagnetic initial configurations on the charging dynamics of the battery. Two charging mechanisms are explored: static charging, where the battery interacts with a constant classical external field, and harmonic charging, where the field oscillates periodically over time. Our results demonstrate that static charging can be more efficient in the ferromagnetic case, achieving maximum energy due to complete population inversion between the ground and excited states. In contrast, harmonic charging excels in the antiferromagnetic case. By analyzing the stored energy and the average charging power in these two regimes, we highlight the impact of anisotropy on the performance of quantum batteries. Our findings provide valuable insights for optimizing quantum battery performance based on the system's initial state and coupling configuration, paving the way for the study of more efficient quantum devices for energy storage.
We consider a quantum battery that is based on a two-level system coupled with a cavity radiation by means of a two-photon interaction. Various figures of merit, such as stored energy, average charging power, energy fluctuations, and extractable work are investigated, considering, as possible initial conditions for the cavity, a Fock state, a coherent state, and a squeezed state. We show that the first state leads to better performances for the battery. However, a coherent state with the same average number of photons, even if it is affected by stronger fluctuations in the stored energy, results in quite interesting performance, in particular since it allows for almost completely extracting the stored energy as usable work at short enough times.