Dumbbell Impurities in 2D Crystals of Repulsive Colloidal Spheres Trap Dislocations

• Published in: Physical review letters Vol. 133; no. 15; p. 158202
• Main Authors: Meester, Vera, van der Wel, Casper, Verweij, Ruben W, Biondaro, Giovanni, Kraft, Daniela J
• Format: Journal Article
• Language: English
• Published: United States 11-10-2024
• ISSN: 0031-9007; 1079-7114; 1079-7114
• DOI: 10.1103/PhysRevLett.133.158202

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 differences in the dumbbell length determine whether it induces a local distortion of the lattice or traps a dislocation, and determine how the dumbbell moves inside the repulsive hexagonal lattice. Our results provide new routes toward controlling material properties and understanding fundamental questions in phase transitions through particle-bound dislocations.