Enhancing the performance of quantum battery by squeezing reservoir engineering

Abstract The reservoir engineering has been widely used in various quantum technologies. Based on a cavity-QED model, we propose a potentially practical scheme using squeezed-vacuum reservoir engineering to optimize the performance of quantum battery (QB), which is inside a cavity driven by a broadband squeezed laser playing the role of a squeezed-vacuum reservoir. Using the reduced master equation of QB through adiabatic elimination method, we focus on the QB’s charging dynamics under the tunable squeezed reservoirs governed by parametrically controlled squeezing parameters, which dictate the efficiency of energy transfer and the extractable work (ergotropy) of QB. We show that increasing the squeezing strength improves the charging rate and enables rapid energy transfer, whereas the steady-state energy of the QB saturates at specific values of the squeezing parameter. Notably, the ergotropy of QB reaches its maximum at a critical squeezing strength and does not scale monotonically with the squeezing strength. This nonmonotonic behavior underscores the existence of optimal parameter regimes, through which the performance of QB can be significantly enhanced.