Superoptimal charging of quantum batteries via reservoir engineering: Arbitrary energy transfer unlocked

Arbitrary energy transfer is only feasible in nondissipative charger-battery systems; in realistic processes, however, energy dissipation prevents this. In this work, we introduce a novel charging technique in which the coherent charger-battery interaction is replaced by a dissipative interaction via an engineered reservoir. We demonstrate that exploiting the collective effects of the engineered reservoir allows for additional optimization, giving rise to an optimal redistribution of energy. This not only significantly enhances the efficiency of the charging process but also remarkably enables the quantum battery to accumulate unlimited energy---limited only by the natural energy scale of the device. This phenomenon cannot occur in conventional charger-battery schemes. The article unveils the intricacies of built-in detuning within the context of a shared environment, offering a deeper understanding of the charging mechanisms involved. These findings apply naturally to quantum circuit battery architectures, suggesting the feasibility of efficient energy storage in these systems. The superoptimal charging mechanism offers a practical avenue for boosting the capacity of the battery through charger-battery configurations.