Benchmark of the Schmiedl-Seifert optimal protocol with reduced dissipated work and fluctuations in optical tweezers

Abstract

Finite-time thermodynamic transformations generally dissipate energy, as required by the Second Law, so identifying and investigating energetically optimal processes remain relevant for understanding and designing efficient thermal devices. In this context, we present here a systematic experimental benchmark of the finite-time minimum-work compression protocol derived by Schmiedl and Seifert for an overdamped Brownian particle in a harmonic trap. By parametrically controlling the trap stiffness, we compare the full work statistics of the analytical optimal protocol with those obtained under linear driving across a broad range of protocol durations and amplitudes. We find that the optimal protocol consistently reduces both the mean work and the work variance relative to linear driving. Although the Schmiedl-Seifert protocol was primarily derived to minimize the mean work, our data show, in the present setting, a clear reduction in fluctuations and high-work tails under realistic bandwidth-limited actuation. This observation connects our benchmark to the growing interest in higher-order cumulants and to current developments in stochastic-thermodynamic control.