Reservoir-assisted quantum battery charging at finite temperatures

TL;DR

This paper investigates how quantum feedback control influences the charging efficiency of quantum batteries in finite-temperature environments, revealing that fermionic reservoirs benefit from higher temperatures while bosonic ones do not.

Contribution

It introduces a novel analysis of quantum battery charging under thermal reservoirs using feedback control, highlighting the contrasting effects of fermionic and bosonic environments on performance.

Findings

Fermionic reservoirs improve performance with higher temperatures.

Bosonic reservoirs see reduced efficiency at higher temperatures.

Optimal charging parameters are identified for different reservoirs.

Abstract

Quantum batteries, as highly efficient energy storage devices, have garnered significant research interest. A key challenge in their development is to maximize the extractable energy (ergotropy) when operating within a finite-temperature reservoir. To address this, we applied quantum feedback control to the charger and investigated the effects of fermionic and bosonic thermal reservoirs on the performance of quantum batteries, including stored energy, ergotropy, and charging efficiency, in an open environment. Our findings reveal that, regardless of the type of thermal reservoir, the system exhibits optimal charging parameters. In particular, in a fermionic thermal reservoir, increasing the environmental temperature enhances battery performance, enabling stable and efficient charging. In contrast, within a bosonic thermal reservoir, higher temperatures hinder energy storage and extraction, significantly reducing charging efficiency. Additionally, we explored the impact of battery size and found that, under a fermionic reservoir, increasing the battery size appropriately can further improve performance.