Quantum Otto engine driven by quantum fields

TL;DR

This paper analyzes a quantum Otto engine powered by quantum fields using an Unruh-DeWitt detector model, deriving conditions for positive work and evaluating work extraction in different spacetime scenarios.

Contribution

It introduces a generic condition for positive work in a quantum Otto engine interacting with quantum fields, extending the understanding of quantum thermodynamics in curved spacetime.

Findings

Derived a condition for positive work based on the detector's effective temperature.

Evaluated work extraction for inertial detectors in thermal baths.

Analyzed circulating detectors in Minkowski vacuum inspired by the Unruh effect.

Abstract

We consider a quantum Otto engine using an Unruh-DeWitt particle detector model which interacts with a quantum scalar field in curved spacetime. We express a generic condition for extracting positive work in terms of the effective temperature of the detector. This condition reduces to the well-known positive work condition in the literature under the circumstances where the detector reaches thermal equilibrium with the field. We then evaluate the amount of work extracted by the detector in two scenarios: an inertial detector in a thermal bath and a circulating detector in the Minkowski vacuum, which is inspired by the Unruh quantum Otto engine.