A double quantum dot quantum battery controlled with a Markovian feedback

A battery is a device that stores energy in the form of work for later use by other devices. In this work, we study the realization of a quantum battery in a double quantum dot in series, charged by two electrodes at different chemical potentials and optimized by a Markovian quantum feedback protocol. Using the concept of ergotropy as a figure of merit, we first establish a simple expression for the maximum ergotropy in a two-level system, and then find the parameters under which Markovian feedback can achieve this optimal ergotropy. We find that quantum coherence can be used as an energy storage resource, and we study the influence of interactions with a phonon environment to mitigate the discharge process with the environment by fine-tuning the system parameters.