Entanglement, coherence and charging process of quantum batteries

TL;DR

This paper investigates how entanglement and coherence influence the performance of quantum batteries, revealing that entanglement is not the primary resource for high efficiency, and highlighting a complex resource trade-off.

Contribution

It provides a general analysis of small quantum batteries, showing that entanglement is not essential for their high performance and exploring the coherence-entanglement trade-off.

Findings

Entanglement is not the main resource for quantum battery efficiency.

A non-trivial correlation-coherence trade-off exists during charging.

Small quantum batteries can perform well without relying on entanglement.

Abstract

Quantum devices are systems that can explore quantum phenomena, like entanglement or coherence, for example, to provide some enhancement performance concerning their classical counterparts. In particular, quantum batteries are devices that use entanglement as main element in its high performance in the charging powerful. In this paper, we explore the quantum battery performance and its relationship with the amount of entanglement that arises during the charging process. By using a general approach to a two and three-cell battery, our results suggest that entanglement is not the main resource to quantum batteries, where there is a non-trivial correlation-coherence trade-off as resource for the high efficiency of such quantum devices.