Properties of twisted topological defects in 2D nematic liquid crystals

TL;DR

This paper investigates twisted topological defects in 2D nematic liquid crystals, revealing how their interactions and motion are governed by attraction, repulsion, co-rotation, and co-translation, with potential for controlled defect dynamics.

Contribution

It introduces the concept of twisted defects with radially dependent orientation and analyzes their interactions and motion mechanisms in 2D nematics.

Findings

Twist can be relaxed via defect pair creation and annihilation.

Four key elements govern defect interactions: attraction, repulsion, co-rotation, co-translation.

Defect trajectories can be controlled by tuning relevant timescales.

Abstract

Topological defects are one of the most conspicuous features of liquid crystals. In two dimensional nematics, they have been shown to behave effectively as particles with both, charge and orientation, which dictate their interactions. Here, we study "twisted" defects that have a radially dependent orientation. We find that twist can be partially relaxed through the creation and annihilation of defect pairs. By solving the equations for defect motion and calculating the forces on defects, we identify four distinct elements that govern the relative relaxational motion of interacting topological defects, namely attraction, repulsion, co-rotation and co-translation. The interaction of these effects can lead to intricate defect trajectories, which can be controlled by setting relevant timescales.