Nucleation of Topologically Equivalent Phases after Annihilation of Topological Defects

Abstract

The annihilation of radial and hyperbolic point defects within an infinite cylinder of radius R in nematic liquid crystals using Brownian molecular dynamics simulations is studied. Unlike some other studies, where they focus on individual phases of annihilation, this paper considers the entire course of annihilation, both before and after the collision of the two defects. After the collision, merging of defects, and building of a ring disclination structure, the system can experience a structural transition into another topologically equivalent nematic structure, triggered by the nucleation of the ring disclination structure. In the article, the condition under which the transition to the topologically equivalent final structure of the molecular arrangement occurs is quantitatively determined. In addition, a comparison of the temporal evolution of the final stable structure is discussed, where, based on a simple dissipation relation, we obtain an equation that agrees well with the simulation results.