Thermodynamics of a Colloidal Particle in a Time-Dependent Non-Harmonic Potential

TL;DR

This paper investigates the thermodynamics of a colloidal particle in a dynamic non-harmonic potential, confirming fundamental fluctuation relations and analyzing work distributions at the single-particle level.

Contribution

It provides the first experimental verification of the first law-like energy balance and fluctuation theorems for a colloidal particle in a non-harmonic, time-dependent potential.

Findings

Confirmed the first law-like energy balance at the single-trajectory level.

Observed non-Gaussian work distributions consistent with numerical models.

Verified the Jarzynski relation and fluctuation theorem with high accuracy.

Abstract

We study the motion of an overdamped colloidal particle in a time-dependent non-harmonic potential. We demonstrate the first law-like balance between applied work, exchanged heat, and internal energy on the level of a single trajectory. The observed distribution of applied work is distinctly non-Gaussian in good agreement with numerical calculations. Both the Jarzynski relation and a detailed fluctuation theorem are verified with good accuracy.