Lost and found charge in quantum batteries

TL;DR

This paper demonstrates that thermal environments can be used to recover and recycle charge in quantum batteries through specific interactions, revealing a link between charge retrieval and entanglement generation.

Contribution

It introduces a novel framework for using thermal environments to recover charge in quantum batteries, highlighting two assistance mechanisms and their relation to entanglement.

Findings

Thermal environments can aid in charge recovery in quantum batteries.

Assistance from a purifying subsystem enhances charge retrieval.

The difference in charge recovery indicates entanglement generated during the process.

Abstract

Quantum batteries are prone to loosing their stored charge, when interacting with a thermal environment. However, getting a limited assistance from the thermal environment, is it possible to recover the charge back, in a reusable form? Here we answer this question affirmatively, leveraging a non-trivial usage of the seemingly useless thermal environment to recycle the quantum batteries. The framework involves two different kind of assistance from thermal environment - one by accessing only the thermal particle, actively participating in the interaction; and the other, involving assistance from an additional purifying subsystem for the thermal environment, bearing a passive role to the interaction. Interestingly, we report that the difference between the retrieved charge between these two degrees of assistance characterizes the amount of entanglement generated by the thermal operation between the quantum battery and the purifying subsystem for the thermal environment.