Phase-ordering dynamics of the Gay-Berne nematic liquid crystal

TL;DR

This study uses molecular dynamics simulations to analyze the phase-ordering process in Gay-Berne nematic liquid crystals, revealing defect dynamics, scaling behavior, and crossover phenomena after a rapid isotropic-to-nematic transition.

Contribution

It provides detailed simulation evidence of defect structures and scaling behavior in Gay-Berne nematics following a quench, highlighting crossover in fluctuation regimes.

Findings

Observation of twist disclination lines and monopoles

Evidence of dynamical scaling in correlation functions

Crossover from defect-dominated to thermal fluctuation regime

Abstract

Phase-ordering dynamics in nematic liquid crystals has been the subject of much active investigation in recent years in theory, experiments and simulations. With a rapid quench from the isotropic to nematic phase a large number of topological defects are formed and dominate the subsequent equilibration process. We present here the results of a molecular dynamics simulation of the Gay-Berne model of liquid crystals after such a quench in a system with 65536 molecules. Twist disclination lines as well as type-1 lines and monopoles were observed. Evidence of dynamical scaling was found in the behavior of the spatial correlation function and the density of disclination lines. However, the behavior of the structure factor provides a more sensitive measure of scaling, and we observed a crossover from a defect dominated regime at small values of the wavevector to a thermal fluctuation dominated regime at large wavevector.