Abstract Black holes constitute nature's fastest quantum information scramblers, a phenomenon captured by gravitational analogue systems such as position‐dependent XY spin chains. In these models, scrambling dynamics are governed exclusively by the hopping interactions profile, independent of system size. Utilizing such curved spacetime analogues as quantum batteries, how the black hole scrambling affects charging via controlled quenches of preset scrambling parameters is explored. This analysis reveals that the intentionally engineered difference between post‐quench and pre‐quench scrambling parameters can significantly enhance both maximum stored energy E max and peak charging power P max in the quench charging protocol. Furthermore, the peaks of extractable work and stored energy coincide. This is because the system's evolution under a weak perturbation remains close to the ground state, resulting in a passive state energy nearly identical to the ground state energy. The optimal charging time τ * exhibits negligible dependence on the preset initial horizon parameter x h 0 , while decreasing monotonically with increasing quench horizon parameter x ht . This temporal compression confines high‐power operation to regimes with strong post‐quench scrambling x ht > x h 0 , demonstrating accelerated charging mediated by spacetime‐mimicking scrambling dynamics.
Abstract Black holes constitute nature's fastest quantum information scramblers, a phenomenon captured by gravitational analogue systems such as position‐dependent XY spin chains. In these models, scrambling dynamics are governed exclusively by the hopping interactions profile, independent of system size. Utilizing such curved spacetime analogues as quantum batteries, how the black hole scrambling affects charging via controlled quenches of preset scrambling parameters is explored. This analysis reveals that the intentionally engineered difference between post‐quench and pre‐quench scrambling parameters can significantly enhance both maximum stored energy E max and peak charging power P max in the quench charging protocol. Furthermore, the peaks of extractable work and stored energy coincide. This is because the system's evolution under a weak perturbation remains close to the ground state, resulting in a passive state energy nearly identical to the ground state energy. The optimal charging time τ * exhibits negligible dependence on the preset initial horizon parameter x h 0 , while decreasing monotonically with increasing quench horizon parameter x ht . This temporal compression confines high‐power operation to regimes with strong post‐quench scrambling x ht > x h 0 , demonstrating accelerated charging mediated by spacetime‐mimicking scrambling dynamics.
A bstract Exponentially fast scrambling of an initial state characterizes quantum chaotic systems. Given the importance of quickly populating higher energy levels from low-energy states in quantum battery charging protocols, this work investigates the role of quantum scrambling in quantum batteries and its effect on optimal power and charging times by means of the Sachdev-Ye-Kitaev model, a maximally-chaotic black hole physics model that has been recently proposed as a quantum battery. We adopt a bare representation with normalized bandwidths to suppress system energy dependence. To our knowledge, this is the first in-depth exploration of quantum scrambling in the context of quantum batteries. By analyzing the dynamics of out-of-time-order correlators, our findings indicate that quantum scrambling does not necessarily lead to faster charging, despite its potential for accelerating the process.
Bosonic modes provide a promising platform for quantum batteries as a result of their unbounded energy spectrum. However, the energy that can be stored during a coherent charging process is limited due to coherent oscillations between the charger and battery. In this work, we show that by introducing a slow quench in the interaction between a coherently driven charger mode and a quadratic oscillator battery, the maximum stored energy and maximum battery power scale algebraically with the quench duration, with exponents controlled by the ramp profile. This finding implies that, quite counterintuitively, slower quenches lead to faster charging. Such a quench suppresses coherent energy oscillations between the battery and the charger, allowing an unbounded increase in power. We further show that, in the ideal closed protocol, the stored energy is fully extractable as ergotropy, while charger dissipation converts the algebraic enhancement into a finite-time scaling window with an optimal quench duration. We also show that the temporal-extensive scaling occurs in a broader context by mapping the system to a coherently driven Tavis-Cummings battery. Finally, we discuss experimentally accessible signatures in superconducting circuit quantum electrodynamics and organic microcavity platforms.
A bstract Collective behavior strongly influences the charging dynamics of quantum batteries (QBs). Here, we study the impact of nonlocal correlations on the energy stored in a system of N QBs. A unitary charging protocol based on a Sachdev-Ye-Kitaev (SYK) quench Hamiltonian is thus introduced and analyzed. SYK models describe strongly interacting systems with nonlocal correlations and fast thermalization properties. Here, we demonstrate that, once charged, the average energy stored in the QB is very stable, realizing an ultraprecise charging protocol. By studying fluctuations of the average energy stored, we show that temporal fluctuations are strongly suppressed by the presence of nonlocal correlations at all time scales. A comparison with other paradigmatic examples of many-body QBs shows that this is linked to the collective dynamics of the SYK model and its high level of entanglement. We argue that such feature relies on the fast scrambling property of the SYK Hamiltonian, and on its fast thermalization properties, promoting this as an ideal model for the ultimate temporal stability of a generic QB. Finally, we show that the temporal evolution of the ergotropy, a quantity that characterizes the amount of extractable work from a QB, can be a useful probe to infer the thermalization properties of a many-body quantum system.
Criticality is widely used to enhance energy storage in quantum batteries. Two criticalities are compared here, one spectral and one dynamical. We ask two questions. Where does the enhancement that criticality brings to a quenched battery come from? And does the best charging performance require a critical point or a critical time? In the anisotropic XY chain, whose dynamics decomposes into independent momentum sectors, the weight each sector transfers to its upper level organizes the response. A closing spectral gap reshapes that weight near the closing momentum, so the stored energy responds sharply and controllably to the quench parameters. What it supplies is tunability rather than a larger maximum. A dynamical quantum phase transition (DQPT) marks the time at which the evolving state becomes orthogonal to its initial state, where the stored energy stays smooth, and equals the energy maximum when the final precession frequencies coincide, as for a flat band away from the critical field. The interacting Ising chain has no momentum sectors, yet its energy maximum and its return peak separate by a tunable margin. Weak quenches reduce the stored energy to the static susceptibility of the quenched operator. These results identify what optimization acts on, the distribution of transition weights and the spread of precession frequencies, and turn the weak-quench response into a probe of the transition order.
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.
Quantum battery capacity, as a critical metric for quantifying energy storage and release in quantum systems, exhibits complex behaviors in curved spacetime and noisy environments. This study focuses on bipartite mixed state, aiming to explore the modulation of quantum battery capacity by Hawking radiation and environmental noise. We find a counterintuitive phenomenon that Hawking radiation can enhance battery capacity, exerting a positive influence on energy storage, a result that stands in stark contrast to the detrimental effects typically associated with entanglement and coherence. When a quantum battery is simultaneously subjected to environmental noise and Hawking radiation, its capacity generally degrades, with the extent of degradation depending on the type of noise. The charging and discharging behaviors largely follow the same patterns observed in the noiseless scenario; however, under a bit flip channel with strong noise intensity, the charging-discharging pattern reverses. In the extreme case of maximum noise intensity, the capacity of the quantum battery under depolarizing noise tends to zero. The underlying physical mechanism lies in the fact that the bit flip channel disrupts the original population distribution of energy levels, thereby altering the average energy of the system and establishing a perturbative environment for bidirectional energy exchange. This differs fundamentally from the phase flip channel. These findings offer a new perspective for the theory of quantum batteries in noninertial reference frames.