Correlation-enhanced Stability of Microscopic Cyclic Heat Engines

TL;DR

This paper demonstrates how tuning driving protocols in microscopic cyclic heat engines can leverage intercycle correlations to significantly reduce work fluctuations, enhancing stability beyond single-cycle performance, with practical experimental feasibility.

Contribution

It introduces a method to enhance heat engine stability by exploiting intercycle correlations, specifically in the Otto engine with Brownian particles, and shows experimental realizability.

Findings

Work fluctuation can be reduced by tuning protocols.

Enhanced stability achieved through intercycle correlation.

Uncertainty of work can be lowered below 50%.

Abstract

For cyclic heat engines operating in a finite cycle period, thermodynamic quantities have intercycle and intracycle correlations. By tuning the driving protocol appropriately, we can get the negative intercycle correlation to reduce the fluctuation of work through multiple cycles, which leads to the enhanced stability compared to the single-cycle operation. Taking the Otto engine with an overdamped Brownian particle as a working substance, we identify a scenario to get such enhanced stability by the intercycle correlation. Furthermore, we demonstrate that the enhancement can be readily realized in the current experiments for a wide range of protocols. By tuning the parameters within the experimentally achievable range, the uncertainty of work can be reduced to below $\sim 50 \%$.