Crystallization kinetics of binary colloidal monolayers

TL;DR

This study combines experiments and simulations to analyze the crystallization process in binary colloidal monolayers, revealing conditions for growing large single crystals and aligning simulation results with experimental data.

Contribution

It introduces a comprehensive approach to understanding colloidal crystal growth, including the effects of impurities and optimal conditions for large crystal formation.

Findings

Largest experimental crystals contain ~1000 particles

Simulations show larger crystals (~5000 particles) possible in impurity-free conditions

Small impurity levels (1-2%) align simulation with experimental results

Abstract

Experiments and simulations are used to study the kinetics of crystal growth in a mixture of magnetic and nonmagnetic particles suspended in ferrofluid. The growth process is quantified using both a bond order parameter and a mean domain size parameter. The largest single crystals obtained in experiments consist of approximately 1000 particles and form if the area fraction is held between 65-70% and the field strength is kept in the range of 8.5-10.5 Oe. Simulations indicate that much larger single crystals containing as many as 5000 particles can be obtained in impurity-free conditions within a few hours. If our simulations are modified to include impurity concentrations as small as 1-2%, then the results agree quantitatively with the experiments. These findings provide an important step toward developing strategies for growing single crystals that are large enough to enable follow-on investigations across many subdisciplines in condensed matter physics.