Topological defects in spherical crystals

Abstract

Spherical crystals present properties that are quite di erent from two-dimensional

at crystals. Due to curvature, they demand the presence of topological defects. In this paper, we study the interplay of these defects on spherical shells, as well as their ground-state configurations, and their out-of-equilibrium dynamics under mechanical deformation. To develop these studies, we have perfomed computer simulations in which particles stay on the surface of a curved template and interact between themselves with a pair-wise potential, either repulsive or attractive. We finally study the mechanical response of these curved crystals when they are subject to cyclic load. We have seen irreversible plastic deformation and the evolution of defects after some cycles of deformation. This plastic behaviour is related to the motion of defects and their spatial distribution and accumulation in the crystal.