Charging performance of quantum batteries in a double-layer environment

In the process of using quantum resources to improve the performance of quantum battery devices, device performance is highly restricted by decoherence due to the influence of the external environment. In particular, the fact that such devices are subject to complex environmental influences in real scenarios should be taken into account. Here, we investigate the performance (i.e., the internal energy, charging power, and ergotropy) of a quantum battery in a double-layer environment, where the first-layer environment is a single-mode cavity and the second-layer environment is a single reservoir. We are surprised to find that the memory effect of the reservoir does not affect the charging performance of a quantum battery; in sharp contrast, the reduction in the coupling between the quantum battery and the first-layer environment can improve the charging performance of a quantum battery. We then extend our discussion to the case where the second-layer environment consists of multiple reservoirs, each consisting of a single-mode cavity dissipated to the Markovian reservoir. It is shown that the charging performance of the quantum battery can be enhanced by increasing the number of cavities in the second-layer environment and the coupling strength between the first-layer environment and the second-layer environment. Our results may be helpful for realizing optimal charging performance of quantum batteries in a complex environment.