Non-equilibrium fluctuations in a driven stochastic Lorentz gas
Abstract
We study the stationary state of a one-dimensional kinetic model where a probe particle is driven by an external field E and collides, elastically or inelastically, with a bath of particles at temperature T. We focus on the stationary distribution of the velocity of the particle, and of two estimates of the total entropy production \Delta s_tot. One is the entropy production of the medium \Delta s_m, which is equal to the energy exchanged with the scatterers, divided by a parameter \theta, coinciding with the particle temperature at E=0. The other is the work W done by the external field, again rescaled by \theta. At small E, a good collapse of the two distributions is found: in this case the two quantities also verify the Fluctuation Relation (FR), indicating that both are good approximations of \Delta s_tot. Differently, for large values of E, the fluctuations of W violate the FR, while \Delta s_m still verifies it.
Cite
@article{arxiv.1111.5798,
title = {Non-equilibrium fluctuations in a driven stochastic Lorentz gas},
author = {G. Gradenigo and U. Marini Bettolo Marconi and A. Puglisi and A. Sarracino},
journal= {arXiv preprint arXiv:1111.5798},
year = {2013}
}
Comments
6 pages, 4 figures