Crystallization dynamics of a single layer complex plasma

TL;DR

This study investigates the re-crystallization process in a two-dimensional complex plasma through experiments and large-scale molecular dynamics simulations, revealing two distinct stages of order formation characterized by power-law growth of crystallite domains.

Contribution

It provides detailed experimental and simulation analysis of the time evolution of re-crystallization in 2D dusty plasma, highlighting two distinct stages of order formation with different dynamics.

Findings

Power-law growth of crystallite size with two distinct exponents

Fast initial stage dominated by individual particle motion

Longer stage involves collective rearrangement and merging of crystallites

Abstract

We report a series of complex (dusty) plasma experiments, aimed at the study of the detailed time evolution of the re-crystallisation process following a rapid quench of a two dimensional dust liquid. The experiments were accompanied by large-scale (million particle) molecular dynamics simulations, assuming Yukawa type inter-particle interaction. Both experiment and simulation show a $\propto t^\alpha$ (power law) dependence of the linear crystallite domain size as measured by the bond-order correlation length, translational correlation length, dislocation (defect) density, and a direct size measurement algorithm. The results show two stages of order formation: on short time-scales individual particle motion dominates; this is a fast process characterized by $\alpha=0.93\pm0.1$. At longer time-scales, small crystallites undergo collective rearrangement, merging into bigger ones, resulting in a smaller exponent $\alpha=0.38\pm0.06$.