Nematic droplets at fibres

TL;DR

This paper numerically investigates nematic droplets on fibres, analyzing their equilibrium textures, defect avoidance, and responses to electric fields, revealing a Freederickzs-like transition and contrasting AC field effects with experiments.

Contribution

It provides a detailed numerical analysis of nematic droplets on fibres, including electric field effects and defect behavior, advancing understanding of their topological and responsive properties.

Findings

Nematic droplets can avoid defect nucleation under certain conditions.

A Freederickzs-like transition occurs above a threshold electric field.

Textures under AC fields resemble static fields, differing from some experiments.

Abstract

The emergence of new techniques for the fabrication of nematic droplets with nontrivial topology provides new routes for the assembly of responsive devices. Here we perform a numerical study of spherical nematic droplets on fibres. We analyse the equilibrium textures and find that, under certain conditions,the nematic can avoid the nucleation of topological defects. We consider in detail a homeotropic nematic droplet wrapped around a fibre with planar anchoring. We investigate the effect of an electric field on the texture of this droplet such type of system. In the presence of a DC field, the system undergoes a Freederickzs-like transition above a given threshold $E_c$. We also consider AC fields, at high and low frequencies, and find that the textures are similar to those observed for static fields, in contrast with recently reported experiments.