Optimal probabilistic work extraction beyond the free energy difference with a single-electron device

TL;DR

This study experimentally demonstrates that a single-electron device can extract work beyond free energy limits using nonequilibrium protocols, highlighting irreversibility as a resource without feedback.

Contribution

It introduces experimental protocols for work extraction beyond free energy differences using a single-electron transistor with nonequilibrium driving cycles.

Findings

Work extraction up to large fractions of k_BT achieved

Probabilities of work extraction significantly greater than 1/2 demonstrated

Work extraction occurs despite zero free energy difference over the cycle

Abstract

We experimentally realize protocols that allow to extract work beyond the free energy difference from a single electron transistor at the single thermodynamic trajectory level. With two carefully designed out-of-equilibrium driving cycles featuring kicks of the control parameter, we demonstrate work extraction up to large fractions of $k_BT$ or with probabilities substantially greater than 1/2, despite zero free energy difference over the cycle. Our results are explained in the framework of nonequilibrium fluctuation relations. We thus show that irreversibility can be used as a resource for optimal work extraction even in the absence of feedback from an external operator.