Disclination motion in hexatic and smectic-C films

TL;DR

This paper provides a theoretical analysis of disclination motion in hexatic and smectic-C films, accounting for back-flow effects and bond angle dynamics, and relates disclination velocity to far-field angle gradients.

Contribution

It introduces a comprehensive theoretical model for disclination dynamics in thin films, including the effects of back-flow and viscosity ratios.

Findings

Disclination velocity is related to the far-field angle gradient.

Velocity distributions around the disclination are characterized.

Different behaviors are identified depending on viscosity ratios.

Abstract

We present theoretical study of a single disclination motion in a thin free standing hexatic (or smectic-C) film, driven by a large-scale inhomogeneity in the bond (or director) angle. Back-flow effects and own dynamics of the bond angle are included. We find the angle and hydrodynamic velocity distributions around the moving disclination, what allows us to relate the disclination velocity to the angle gradient far from the disclination. Different cases are examined depending on the ratio of the rotational and shear viscosity coefficients.