Quantum thermal machine as a rectifier

TL;DR

This paper investigates a quantum thermal machine that functions as a heat rectifier, exploring conditions for asymmetric heat conduction, effects of coupling strength, and its potential as a resource-consuming device producing entanglement.

Contribution

It introduces a quantum thermal machine model that acts as a rectifier, analyzing both weak and strong coupling regimes and their impact on heat transport and entanglement.

Findings

Heat rectification can be independent of chain length in weak coupling.

Negative differential thermal conductance is observed.

Strong coupling enhances rectification and heat transport via Rabi-type splitting.

Abstract

We study a chain of interacting individual quantum systems connected to heat baths at different temperatures on both ends. Starting with the two-system case, we thoroughly investigate the conditions for heat rectification (asymmetric heat conduction), compute thermal conductance, and generalize the results to longer chains. We find that heat rectification in the weak coupling regime can be independent of the chain length and that negative differential thermal conductance occurs. We also examine the relationship between heat rectification with entanglement and the entropy production. In the strong coupling regime, the system exhibits an asymmetric Rabi-type splitting in the thermal conductance, leading to enhanced heat transport and improved rectification inaccessible in the weak coupling. This setup represents the simplest quantum thermal machine that consumes incoherent resources and delivers entanglement while acting as a rectifier and heat valve.