Suppressing coherence effects in quantum-measurement based engines

TL;DR

This paper introduces a universal framework for quantum engines powered by measurements, showing that controlling measurement bases can enhance performance and reduce entropy, extending quantum thermodynamics beyond thermal reservoirs.

Contribution

It proposes a new measurement-based approach to quantum engines that can outperform traditional thermal reservoir models by optimizing measurement bases.

Findings

Replacing thermal reservoirs with measurement operations can improve engine efficiency.

Controlling measurement basis angles reduces entropy production.

Measurement-based engines can surpass standard quantum thermal machines.

Abstract

The recent advances in the study of thermodynamics of microscopic processes have driven the search for new developments in energy converters utilizing quantum effects. We here propose a universal framework to describe the thermodynamics of a quantum engine fueled by quantum projective measurements. Standard quantum thermal machines operating in a finite-time regime with a driven Hamiltonian that does not commute in different times have the performance decreased by the presence of coherence, which is associated with a larger entropy production and irreversibility degree. However, we show that replacing the standard hot thermal reservoir by a projective measurement operation with general basis in the Bloch sphere and controlling the basis angles suitably could improve the performance of the quantum engine as well as decrease the entropy change during the measurement process. Our results go in direction of a generalization of quantum thermal machine models where the fuel comes from general sources beyond the standard thermal reservoir.