15 January, 2010
Lecture 1: Kinetically constrained models
Lecture 2: Dynamical facilitation: KCM's as realistic models
Abstract
Kinetically constrained models (KCMs) are model systems that share many dynamical features with glass-forming liquids. They have simple thermodynamic properties, but they evolve by stochastic rules that lead to complex behaviour [1]. In particular, at low temperatures, their relaxation times increase dramatically, while motion in the systems becomes increasingly intermittent and heterogeneous. We shall introduce some KCMs and discuss the range of behaviour that they exhibit, including increasing static and dynamical length scales, breakdown of the Stokes-Einstein relation, and different kinds of critical phenomena. We then discuss how these models encapsulate the dynamical facilitation scenario for glassy behaviour [2], and we compare this approach with other theoretical pictures. Finally, we will touch on recent work that exploits ideas from KCMs in order to identify “ideal glass” states in computer simulations.
References and suggested reading
- F Ritort and P Sollich, Adv. Phys. 52, 219 (2003) http://uk.arxiv.org/abs/cond-mat/0210382
- J P Garrahan and D Chandler, Proc. Nat. Acad. Sci. 100, 9710 (2003)