Heterogeneous crystallization in colloids and complex plasmas: the role of binary mobilities

Both charged colloidal suspensions and complex (dusty) plasmas represent classical many-body strongly coupled Coulomb systems. Here we discuss their basic properties and focus on their heterogeneous crystallization from an undercooled melt. In particular, a model with different mobilities is proposed which is realizable in binary mixtures of charged particles. Within this binary-mobility model, the crystallization behaviour near a structured wall is explored by Brownian dynamics computer simulations. As a result, the propagation velocity of the crystal-fluid interface is a nonmonotonic function of the mobility ratio (if expressed in terms of an averaged mobility). (paper)