Eur. Phys. J. B (2014) 87: 277
https://doi.org/10.1140/epjb/e2014-50622-2

Regular Article

Thermal response in driven diffusive systems

¹ Department of Physics and Astronomy, University of Padua, Via Marzolo 8, 35131 Padova, Italy
² INFN, Sezione di Padova, Via Marzolo 8, 35131 Padova, Italy
³ Instituut voor Theoretische Fysica, 3001 Leuven, Belgium

^a e-mail: baiesi@pd.infn.it

Received: 11 September 2014
Received in final form: 17 October 2014
Published online: 24 November 2014

Abstract

Evaluating the linear response of a driven system to a change in environment temperature(s) is essential for understanding thermal properties of nonequilibrium systems. The system is kept in weak contact with possibly different fast relaxing mechanical, chemical or thermal equilibrium reservoirs. Modifying one of the temperatures creates both entropy fluxes and changes in dynamical activity. That is not unlike mechanical response of nonequilibrium systems but the extra difficulty for perturbation theory via path-integration is that for a Langevin dynamics temperature also affects the noise amplitude and not only the drift part. Using a discrete-time mesh adapted to the numerical integration one avoids that ultraviolet problem and we arrive at a fluctuation expression for its thermal susceptibility. The algorithm appears stable under taking even finer resolution.