Dynamics of transient cages in a model 2D supercooled liquid

Abstract

Supercooled state of a liquid is characterized by extremely slow and spatially heterogeneous dynamics attributed to caging of particles by their neighbors. The dynamics of cages in a model 2D supercooled liquid is studied by analyzing single particle trajectories. The temperature dependence of cage times and cage sizes is discussed. The average cage time is found to show power-law divergence as the critical temperature is approached. A correlation between cage sizes and cage survival time is identified. At higher temperatures, bigger cages survive for longer. However, this behavior changes at low enough temperatures, where a crossover timescale is observed beyond which the smallest cages are more likely to survive. This crossover time originates mainly due to different initial dynamics of the bigger and the smaller cages, which shows strong temperature dependence for smaller cages.