Publication of the Physics Laboratory in the Physical Review Letters on July 31, 2024. Communication by CNRS Physics on September 2, 2024.
Experiments on a classical microscopic system show that, while the second principle of thermodynamics is still valid on average, it can be circumvented experimentally in 95% of cases! A study conducted at the Physics Laboratory of ENS de Lyon, published in Physical Review Letters.
Abstract
We demonstrate experimentally that, applying optimal protocols that drive the system between two equilibrium states characterized by a free energy difference Δ𝐹, we can maximize the probability of performing the transition between the two states with a work 𝑊 smaller than Δ𝐹. The second law holds only on average, resulting in the inequality ⟨𝑊⟩≥Δ𝐹. The experiment is performed using an underdamped oscillator evolving in a double-well potential. We show that with a suitable choice of parameters the probability of obtaining trajectories with 𝑊≤Δ𝐹 can be larger than 95%. Very fast protocols are a key feature to obtain these results, which are explained in terms of the Jarzynski equality.
Credit: Ludovic Bellon
Reference
Probabilistic Work Extraction on a Classical Oscillator Beyond the Second Law. Nicolas Barros, Sergio Ciliberto, and Ludovic Bellon. Phys. Rev. Lett., July 31, 2024.
DOI : 10.1103/PhysRevLett.133.057101
Open archive arXiv: 10.48550/arXiv.2402.18556