Maxwell’s demon and the first passage time
Sergio Ciliberto (ENS, Lyon)
Using a mechanical cantilever submitted to electrostatic feedback control, we investigate the thermodynamic properties of an information engine that extracts work from thermal fluctuations. The cantilever position is rapidly sampled and the feedback is triggered by the first passage of the system across a fixed threshold. The information ΔI associated with the feedback is based on the first-passage time distribution. In this setting, we derive and experimentally verify two distinct fluctuation theorems that involve ΔI and give a tight bound on the work produced by the engine. The first passage time distribution is experimentally measured and theoretically estimated. The knowledge of the mean first passage time allows us to compute the mean power of the information engine, which agrees with that experimentally measured.
A. Archambault, C. Crauste-Thibierge , A. Imparato , S. Ciliberto, L. Bellon, arXiv:2607.01405
A. Archambault, C. Crauste-Thibierge , A. Imparato , C. Jarzynski, S. Ciliberto, L. Bellon, PRL135, 147101 (2025)