Stochastic thermodynamics: Theory and experiments
Prof. Udo Seifert
University of Stuttgart
Stochastic thermodynamics provides a framework for describing small systems embedded in a heat bath and externally driven to non-equilibrium. Examples are colloidal particles in time-dependent optical traps, single biomolecules manipulated by optical tweezers or AFM tips, and motor proteins driven by ATP excess. A first-law like energy balance allows to identify applied work and dissipated heat on the level of a single stochastic trajectory.
Total entropy production includes not only this heat but also changes in entropy associated with the state of the small system which leads to a refinement of the second law. For non-equilibrium steady states a generalization of the Einstein relation between diffusion coefficient and mobility has been checked experimentally. Analogues to a Carnot-machine and a machine with optimal power output operating between two temperature baths including the effect of fluctuations will be also be discussed.