Coherently Driven Quantum Harmonic Oscillator Battery

Recently, quantum harmonic oscillator (QHO) battery models have been studied with importance because these experimentally realizable batteries have high ergotropy and capacity to store more than one quanta of energy. However, the following fundamental questions are not yet answered: Do these models have any benefit? Are these models stable against the environment? These questions are answered both numerically and analytically by considering a model that allows a laser to shine on a QHO charger, which interacts with a QHO battery. The laser frequency is tuned with the local frequencies of the charger and battery (off-resonance) or the frequency of the global charger-battery system (on-resonance). It is shown that for a fixed laser field amplitude, in the off-resonance (on-resonance) charging process, the maximum energy stored in a battery depends on the detuning and coupling strength (charger dissipation constant). The charging process of the open QHO, which is a simplified model, is also discussed. Further, the charging process of QHO in the simplified model is observed to be faster than the same for the catalytic and non-catalytic batteries. The self-discharging process is found to be almost doubly faster than the charging process, implying that the QHO batteries are unstable against the environment.