Dynamics of defects in active nematics

TL;DR

This paper investigates the movement and interactions of defects in active nematic layers, revealing that self-propulsion and topological interactions dominate defect dynamics over passive and active flows.

Contribution

It introduces a novel asymptotic matching approach to analyze defect dynamics, highlighting the primary role of self-propulsion and topological interactions.

Findings

Self-propulsion is the main driver of defect motion.

Topological interactions significantly influence defect behavior.

Passive backflow and active flow are less impactful than previously thought.

Abstract

Defect dynamics in a thin active nematic layer is studied by asymptotic matching of solutions in the defect core and the far field. The analysis is facilitated by the correspondence between the 2D nematic and complex scalar field models. Self-propulsion and topological interactions are identified as the primary drivers of the defect motion, surpassing the influence of both passive backflow and active flow induced by other defects.