6533b85afe1ef96bd12b9696
RESEARCH PRODUCT
Aging in a free-energy landscape model for glassy relaxation. II. Fluctuation-dissipation relations.
Gregor DiezemannRoland Böhmersubject
Correlation function (statistical mechanics)ChemistrySpin–lattice relaxationGeneral Physics and AstronomyEnergy landscapeRelaxation (physics)Dielectric lossStatistical physicsPhysical and Theoretical ChemistryDissipationSupercoolingMeasure (mathematics)description
Several fluctuation-dissipation relations are investigated for a simple free-energy landscape model designed to describe the primary relaxation in supercooled liquids. The calculations of the response and of the correlation functions are performed for a quench from a high temperature to a low temperature. In the model, all dynamical quantities reach equilibrium after long times, but for times shorter than the re-equilibration time they do not exhibit time-translational invariance and the fluctuation-dissipation theorem is violated. Two measures for these violations are considered. One such measure is given by the slope in a plot of the integrated response versus the correlation function and another one by the so-called fluctuation-dissipation ratio. It is found that these measures do not coincide and furthermore are not independent of the dynamical variable considered in the calculation. We propose to determine the fluctuation-dissipation ratio experimentally via measurements of the deuteron spin-lattice relaxation rate and the dielectric loss.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2006-06-07 | The Journal of chemical physics |