Liquid crystal torons in Poiseuille-like flows

TL;DR

This study uses 3D simulations to explore how liquid crystal torons behave under flow conditions, revealing steady states, disintegration, and reversible elongation, which are consistent with experimental observations and differ from 2D models.

Contribution

First 3D simulation analysis of liquid crystal torons under flow, highlighting their behavior and coupling with flow, contrasting previous 2D results.

Findings

Torons reach steady state at low flow velocities.

At higher velocities, torons disintegrate.

Flow induces reversible elongation of torons under partial slip conditions.

Abstract

Three-dimensional (3D) simulations of the structure of liquid crystal (LC) torons, topologically protected distortions of the LC director field, under material flows are rare but essential in microfluidic applications. Here, we show that torons adopt a steady-state configuration at low flow velocity before disintegrating at higher velocities, in line with experimental results. Furthermore, we show that under partial slip conditions at the boundaries, the flow induces a reversible elongation of the torons, also consistent with the experimental observations. These results are in contrast with previous simulation results for 2D skyrmions under similar flow conditions, highlighting the need for a 3D description of this LC soliton in relation to its coupling to the material flow. These findings pave the way for future studies of other topological solitons, like hopfions and heliknotons, in flowing soft matter systems.