Fully selective charging of a quantum battery by a purely quantum charger

TL;DR

This paper presents a protocol for fully charging a quantum battery using a quantum charger, leveraging quantum coherence and symmetries to optimize energy transfer and extend applications to state resetting.

Contribution

It introduces a universal, fully selective charging protocol for quantum batteries with a quantum harmonic oscillator charger, including extensions for quantum coherence and state resetting.

Findings

Achieves full charge of a quantum battery with a bipartite quantum charger.

Utilizes quantum coherence as an energetic resource for charging multiple batteries.

Adapts the protocol for active state resetting in quantum computation.

Abstract

In this paper we discuss a protocol for charging a two-level quantum battery using a bipartite charger composed of two quantum harmonic oscillators. As one of its features, it allows us to fully charge the battery and is universally optimal in the regime of a single excitation added as energy input. We also make use of a selective interaction to extend the protocol for a different class of quantum states and show that, in this case, the presence of quantum coherence can be harnessed as energetic resource to charge multiple similar batteries. Among these, we also explore symmetries of the derived effective dynamics to quickly discuss how the same protocol can be adapted to the task of \textit{active state resetting}, a task which is particularly useful in the quantum computation area.