Role of quantum correlations in light-matter quantum heat engines

TL;DR

This paper investigates how quantum correlations in a light-matter system influence the performance of a quantum Otto engine, revealing that their manipulation can enhance work output and efficiency.

Contribution

It introduces a model of a quantum Otto engine with a generalized quantum Rabi system and uncovers the role of quantum correlations and anharmonic spectrum in engine performance.

Findings

Quantum correlations reduction enhances work extraction.

Quantum correlations reduction improves efficiency.

Anharmonic spectrum affects transition from heat engine to refrigerator.

Abstract

We study a quantum Otto engine embedding a working substance composed by a two-level system interacting with a harmonic mode. The physical properties of the substance are described by a generalized quantum Rabi model arising in superconducting circuits realizations. We show that light-matter quantum correlations reduction during the hot bath stage and compression stage act as a resource for enhanced work extraction and efficiency respectively. Also, we demonstrate that the anharmonic spectrum of the working subtance has a direct impact on the transition from heat engine into refrigerator as the light-matter coupling is increased. These results shed light on the search for optimal conditions in the performance of quantum heat engines.