Performance of optimal linear-response processes in driven Brownian motion far from equilibrium

TL;DR

This study investigates the effectiveness of optimal linear-response processes in driven Brownian motion far from equilibrium, demonstrating their surprising performance even in regimes where they were not expected to excel.

Contribution

The paper provides a numerical analysis comparing approximate and exact optimal processes in driven Brownian motion, highlighting their relevance to experimental conditions.

Findings

Optimal linear-response processes perform well far from equilibrium.

Perturbative methods can accurately estimate irreversible work in complex regimes.

The study validates the use of linear-response approximations in experimental settings.

Abstract

Considering the paradigmatic driven Brownian motion, we perform extensive numerical analysis on the performance of optimal linear-response processes far from equilibrium. We focus on the overdamped regime where exact optimal processes are known analytically, and most experiments operate. This allows us to compare the optimal processes obtained in linear response and address their relevance to experiments, using realistic parameter values from experiments with optical tweezers. Our results help assess the accuracy of perturbative methods in calculating the irreversible work for cases where an exact solution does not exist. For that, we present a performance metric comparing the approximate optimal solution to the exact one. Our main result is that optimal linear-response processes can perform surprisingly well, even far from where they were expected.