Stationary and transient Fluctuation Theorems for effective heat flux between hydrodynamically coupled particles in optical traps

A Bérut (1) , A Imparato (2) , A Petrosyan (1) , S Ciliberto (1)

1 Phys-ENS - Laboratoire de Physique de l'ENS Lyon
2 Department of Physics and Astronomy [Aarhus]

We experimentally study the statistical properties of the energy fluxes between two trapped Brownian particles, interacting through dissipative hydrodynamic coupling, submitted to an effective temperature difference ∆T , obtained by random forcing the position of one trap. We identify effective heat fluxes between the two particles and show that they satisfy an exchange fluctuation theorem (xFT) in the stationary state. We also show that after the sudden application of a temperature gradient ∆T , the hot-cold flux satisfies the transient xFT for any integration time whereas the cold-hot flux only does it asymptotically for long times.

Mots clés: optical tweezers; fluctuation theorem; heat exchange; effective temperature; Brownian motion; stochastic thermodynamics

Domaines: Mécanique statistique [cond-mat.stat-mech]; Matière Molle [cond-mat.soft]

A Bérut, A Imparato, A Petrosyan, S Ciliberto. Stationary and transient Fluctuation Theorems for effective heat flux between hydrodynamically coupled particles in optical traps. 2015. ⟨hal-01216722v1⟩