Maximal power for heat engines: role of asymmetric interaction times

TL;DR

This paper explores how asymmetrically adjusting interaction times in quantum heat engines can significantly boost power output and slightly improve efficiency, offering new optimization strategies in nonequilibrium thermodynamics.

Contribution

It introduces the concept of asymmetric interaction times as a means to optimize quantum heat engine performance, demonstrating potential power increases over symmetric protocols.

Findings

Asymmetric interaction times can increase power output by over 25%.

Optimized protocols yield efficiencies slightly above the Curzon-Ahlborn limit.

Asymmetry plays a crucial role in enhancing quantum heat engine performance.

Abstract

The performance of endoreversible thermal machines operating at finite power constitutes one of the main challenges of nonequilibrium classical and quantum thermodynamics, engineering and others. We introduce the idea of adjusting the interaction time asymmetry in order to optimize the engine performance. We consider one of the simplest thermal machines, composed of a quantum dot interacting sequentially with two different reservoirs of heat and particles. Distinct optimization protocols are analyzed in the framework of stochastic thermodynamics. Results reveal that asymmetric interaction times play a fundamental role in enhancing the power output and that maximizations can provide an increase larger than 25\% the symmetric case. As an extra advantage, efficiencies at maximum power are slightly greater than the endoreversible Curzon-Ahlborn efficiency for a broad range of reservoir temperatures.