Glassy system dynamics

Glassy Systems A Probe for Cooperative Dynamical Length Scales. 

The aim of this chapter is to show how the concepts of FDT violation and effective temperature can be illustrated in the framework of the above quoted system, as done experimentally in Ref. 12 and theoretically in Refs. 15-19. We do not discuss here the vast general domain of aging effects in glassy systems, which are reviewed in Refs. 2-4. Since the present contribution should be understood by beginners in the field, some relevant fundamental topics of equilibrium statistical physics—namely, on the one hand, the statistical description of a system coupled to an environment and, on the other hand, the fluctuation-dissipation theorem (in a time domain formulation)—are first recalled. Then, questions specifically related to out-of-equilibrium dynamics, such as the description of aging effects by means of an effective temperature, are taken up in the framework of the above-quoted model system. 

L. F. Cugliandolo, Dynamics of glassy systems, in Slow Relaxations and Nonequilibrium Dynamics in Condensed Matter, Les Houches—Ecole d Ete de Physique Theorique, Vol. 

L. F. Cugliandolo and G. Lozano, Real-time nonequilibrium dynamics of quantum glassy systems. Phys. Rev. B 59, 915 (1999). 

An aspect of the ES FR that has not been fully exploited as yet is the fact that the dissipation function is sensitive to the choice of the distribution function. Therefore, if a system is presumed to have a particular equilibrium distribution function, with an associated dissipation function, then a field is applied, the transient ES FR should be satisfied for all time. This provides a way of testing if a system is equilibrated, for example. If the FR is not satisfied for the presumed Q, then it indicates that the equilibrium state is not what was expected. This fact has recently been used to establish that domains of the nondissipative, nonequilibrium distributions of glassy systems can be described by Boltzmann weights. Apart from the reversibility of the dynamics, the other key assumption in the derivation of the transient ES FR is that the initial distribution and the dynamics are ergodically consistent. In the same paper, Williams and Evans demonstrated that away from the actual glass... 

Evidence for coupling between glassy matrix dynamics and protein dynamics is not restricted to low-temperature aqueous systems. Studies of the kinetics of... 

In a simple hydrodynamic approach, transport parameters such as the ionic conductivity <7 , the diffusion coefficient D , and the electrochemical mobility Ui of ionic/atomic species i in Uquid/glassy systems are linked to the dynamic viscosity t] by the Stokes-Einstein equation ... 

Del Popolo and Voth computed dynamical properties at 400 K and observed very long overall rotational relaxation times, consistent with the slow dynamics observed by Margulis, Stern, and Berne as well as by Morrow and Maginn. They showed the clearest evidence up to that point that the dynamic motion of ionic liquids bears a resemblance to that of supercooled or glassy systems, an issue that will be described more fully later in this chapter. 

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