Publication Title
Physical Review Letters
Publication Date
1-24-2013
Document Type
Article
DOI
10.1103/PhysRevLett.110.047801
Keywords
2 dimensions, transition, diffusion, liquids, systems, order
Disciplines
Physics
Abstract
A two-dimensional (2D) solid lacks long-range positional order and is diffusive by means of the cooperative motion of particles. We find from molecular dynamics simulations of hard discs that 2D colloids in solid and hexatic phases show seemingly Fickian but strongly heterogeneous dynamics. Beyond translational relaxation time, the mean-square displacement is linear with time, t, implying that discs would undergo Brownian diffusion and the self-part of the van Hove correlation function [G(s)(r, t)] might be Gaussian. But dynamics is still heterogeneous and G(s)(r, t) is exponential at large r and oscillatory with multiple peaks at intermediate length. We attribute the existence of several such peaks to the observation that there are several clusters of discs with discretized mobility. The cluster of marginally mobile discs grows with time and begins to percolate around translational relaxation time while clusters of fast discs emerge in the middle of the marginally mobile cluster.
Recommended Citation
Kim, Jeongmin; Kim, Chanjoong; and Sung, Bong June (2013). Simulation Study of Seemingly Fickian but Heterogeneous Dynamics of Two Dimensional Colloids. Physical Review Letters 110(4). doi: 10.1103/PhysRevLett.110.047801 Retrieved from https://digitalcommons.kent.edu/cpippubs/184
Comments
Copyright 2013 American Physical Society. Available on publisher's site at http://dx.doi.org/10.1103/PhysRevLett.110.047801