Charging power and stability of always-on transitionless driven quantum batteries

Abstract

The storage and transfer of energy through quantum batteries are key elements in quantum networks. Here, we propose a charger design based on transitionless quantum driving (TQD), which allows for inherent control over the battery charging time, with the speed of charging coming at the cost of the internal energy available to implement the dynamics. Moreover, the TQD-based charger is also shown to be locally stable, which means that the charger can be disconnected from the quantum battery (QB) at any time after the energy transfer to the QB, with no full energy backflow to the charger. This provides a highly charged QB in an always-on asymptotic regime. We illustrate the robustness of the QB charge against time fluctuations and the full control over the evolution time for a feasible TQD-based charger.

Exergy and Quantum Batteries

“…After the extraction of ergotropy, it is established that the internal energy of the system does not diminish to zero [12,33], thereby leaving a residual amount of energy still accessible within the system. To measure the amount of energy that can be extracted following ergotropy's extraction, one can analyze the system's dynamics, as illustrated in Figure 2 [25].…”

Optimal charging of a superconducting quantum battery

“…In our system, the energy is introduced in a stable way by employing an adiabatic dynamics with time-varying external fields to inject energy into the system, in which the driving Hamiltonian is given in equation ( 2). Due to the adiabatic theorem validity conditions, the charging speed is negatively impacted leading to a loss of power (energy per time) [54]. To bypass this issue, we explore the optimization process through adiabatic quantum brachistochrone (AQB) [43] to speed up the QB ergotropy loading in the context of adiabatic dynamics.…”

Enhancing self-discharging process with disordered quantum batteries

“…In addition, it is possible to show that this behavior is associated to the system disorder and it can be explained as follows. Let us consider the free ergotropy written in the following for E(ρ, H 0 ) = U(ρ, H 0 ) − U 0 (ρ, H 0 ), where U 0 (ρ, H 0 ) = n ̺ n (t)ε n and the free internal energy U(ρ, H 0 ) = tr(ρH 0 ) is computed concerning the free Hamiltonian H 0 [35]. Then, by taking the time variation of E(ρ, H 0 ) in an infinitesimal time interval dt ≥ 0, we get…”