Cavity magnomechanical framework for a high-efficiency quantum battery

Abstract: We theoretically investigate a quantum battery architecture where two identical two-level atoms are charged by a cavity-magnomechanical system, which includes a microwave cavity, a magnon mode hosted in a YIG sphere, and phonon mode due to the deformation of the YIG sphere. The charging process relies on coherent energy exchange, where the atoms couple to the cavity, which in turn, it interacts with the magnon mode via a beam-splitter mechanism. By deriving the system Hamiltonian under the rotating-wave approximation and employing a Lindblad master equation to rigorously model dissipation, we analyze the complete dynamical evolution of the battery. Our study demonstrates that strong, resonant light-matter interactions are crucial for enhancing the key performance metrics: charging efficiency, stored energy, and ergotropy (extractable work). We systematically investigate the deleterious effects of detuning and decoherence, and critically, we uncover a non-trivial interplay between the system's coupling strengths. This reveals optimal operating regimes where constructive interference maximizes performance, while excessive coupling in specific channels can degrade it. Ultimately, our findings provide a quantitative framework for engineering high-efficiency quantum batteries in hybrid magnonic platforms, offering a design roadmap for future experimental realizations.