Experimental study of work fluctuations in a harmonic oscillator

TL;DR

This experimental study investigates work fluctuations in a driven harmonic oscillator, confirming fluctuation theorems and analyzing finite-time corrections, with implications for free energy calculations using Jarzynski's equality.

Contribution

It provides experimental validation of fluctuation theorems in a harmonic oscillator and examines finite-time effects and the impact of work definitions on free energy estimates.

Findings

Both transient and stationary fluctuation theorems hold.

Finite time corrections differ from those in a first order Langevin model.

Choice of 'good work' affects free energy calculations.

Abstract

The work fluctuations of a harmonic oscillator in contact with a thermostat and driven out of equilibrium by an external force are studied experimentally. For the work both the transient and stationary state fluctuation theorems hold. The finite time corrections are very different from those of a first order Langevin equation. The heat and work fluctuations are studied when a periodic forcing is applied to the oscillator. The importance of the choice of the ''good work'' to compute the free energy from the Jarzinsky equality is discussed.