• Corpus ID: 252568085

Charging by quantum measurement

@inproceedings{Yan2022ChargingBQ,
  title={Charging by quantum measurement},
  author={Jiazhen Yan and Jun Jing},
  year={2022}
}

• Jiazhen Yan, J. Jing
• Published 28 September 2022
• Physics

We propose a quantum charging scheme fueled by measurements on ancillary qubits serving as disposable chargers. A stream of identical qubits are sequentially coupled to a quantum battery of N + 1 levels and measured by projective operations after joint unitary evolutions of optimized intervals. If qubit-chargers are prepared in excited state and measured on ground state, their excitations (energy) can be near-completely transferred to battery by iteratively updating the optimized measurement intervals. Starting from its ground state, the battery could be constantly charged to an even higher energy level. Starting from a thermal state, the battery could also achieve a near-unit rate of ergotropy and energy under ∼ N measurements, when a population inversion occurs. If qubit-chargers are prepared in ground state and measured on excited state, useful work extracted by measurements alone could transform the battery from a thermal state to a high-ergotropy state before the success probability vanishes. Our findings reveal novel features of quantum measurement on shaping the nonequilibrium system.