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arXiv · 2010.00267

Dumbbell impurities in 2D crystals of repulsive colloidal spheres induce particle-bound dislocations

Vera Meester·Casper van der Wel·Ruben W. Verweij·Giovanni Biondaro·Daniela J. Kraft
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Abstract

Impurity-induced defects play a crucial role for the properties of crystals, but little is known about impurities with anisotropic shape. Here, we study how colloidal dumbbells distort and interact with a hexagonal crystal of charged colloidal spheres at a fluid interface. We find that subtle changes in the dumbbell length induce a transition from a local distortion to a particle-bound dislocation, and determine how the dumbbell moves inside the repulsive hexagonal lattice. Our results provide new routes towards controlling material properties through particle-bound dislocations.

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Vera Meester, Casper van der Wel, Ruben W. Verweij, Giovanni Biondaro, Daniela J. Kraft. 2020-10-01. Dumbbell impurities in 2D crystals of repulsive colloidal spheres induce particle-bound dislocations. https://arxiv.org/abs/2010.00267

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