Topological Defects by Size Polydispersity*

The engineering of defects in crystalline matter introduces entirely new physical properties of materials. The fascinating possible applications of defects, known as topological defects, provide great motivations to perform fundamental investigations to uncover their role on the physical properties of various systems. Here we investigate topological defects in size polydispersity on flat surfaces. Our simulations show that in polydispersed systems topological defects play the role of order-restoring. The perfect hexagonal lattice beyond a small defective region around the impurity particle is well protected. Moreover, size polydispersity is shown numerically here to be an essential ingredient to understand short-range attractions between like-charge disclinations. Our study suggests the promising potential of size polydispersity to engineer defects in real systems.