Are quantum thermodynamic machines better than their classical counterparts?

TL;DR

This paper explores whether quantum thermodynamic machines outperform classical ones by examining energy transfer effects like heat and ergotropy, which can surpass classical efficiency bounds without requiring quantum mechanics.

Contribution

The paper analyzes the role of heat and ergotropy in cyclic machines, highlighting that quantum effects are not essential for achieving efficiency bounds beyond classical limits.

Findings

Unconventional energy decompositions can surpass Carnot efficiency

Quantum effects are not necessary for enhanced efficiency

Heat and ergotropy are key factors in energy transfer

Abstract

Interesting effects arise in cyclic machines where both heat and ergotropy transfer take place between the energising bath and the system (the working fluid). Such effects correspond to unconventional decompositions of energy exchange between the bath and the system into heat and work, respectively, resulting in efficiency bounds that may surpass the Carnot efficiency. However, these effects are not directly linked with quantumness, but rather with heat and ergotropy, the likes of which can be realised without resorting to quantum mechanics.