Nonequilibrium fluctuations in a resistor
Abstract
In small systems where relevant energies are comparable to thermal agitation, fluctuations are of the order of average values. In systems in thermodynamical equilibrium, the variance of these fluctuations can be related to the dissipation constant in the system, exploiting the fluctuationdissipation theorem. In nonequilibrium steady systems, fluctuations theorems (FT) additionally describe symmetry properties of the probability density functions (PDFs) of the fluctuations of injected and dissipated energies. We experimentally probe a model system: an electrical dipole driven out of equilibrium by a small constant current I , and show that FT are experimentally accessible and valid. Furthermore, we stress that FT can be used to measure the dissipated power P̄ =R I^{2} in the system by just studying the PDFs’ symmetries.
 Publication:

Physical Review E
 Pub Date:
 June 2005
 DOI:
 10.1103/PhysRevE.71.060101
 arXiv:
 arXiv:condmat/0407574
 Bibcode:
 2005PhRvE..71f0101G
 Keywords:

 05.40.a;
 05.70.a;
 07.50.e;
 84.30.Bv;
 Fluctuation phenomena random processes noise and Brownian motion;
 Thermodynamics;
 Electrical and electronic instruments and components;
 Circuit theory;
 Statistical Mechanics
 EPrint:
 Juillet 2004