Enhancing the efficiency of quantum measurement-based engines with entangling measurements

TL;DR

This paper demonstrates that entangling measurements can significantly improve the efficiency of quantum measurement-based engines, especially with many subsystems, potentially achieving perfect efficiency with finite work output.

Contribution

It introduces the concept that entangling measurements enhance engine efficiency and shows conditions under which perfect efficiency with finite work is possible.

Findings

Efficiency increases with entangling measurements for many subsystems.

Efficiency improvement is proportional to correlations in the system.

Two-level systems can reach perfect efficiency with finite work in large systems.

Abstract

We study the impact of entangling measurements on the efficiency of quantum measurement- based engines. We first show that for engines comprising many subsystems their efficiency can be enhanced by performing entangling measurements, as opposed to local measurements over each subsystem. When the collective measurement produces the same local state for the subsystems as individual local measurements, the improvement in the efficiency is proportional to the amount of correlations. Finally, we show that for two level systems these type of engine can operate at perfect efficiency while yielding a finite amount of work, in the limit large the number of subsystems.