Rectified Rotational Dynamics of Mobile Inclusions in Two-Dimensional Active Nematics

TL;DR

This paper explores how the shape and boundary conditions of inclusions affect their motion in 2D active nematics, revealing rectified rotation in chiral inclusions linked to defect dynamics and offering new tools for probing active matter rheology.

Contribution

It demonstrates that chiral gear-shaped inclusions exhibit long-term rectified rotation in active nematics, connecting defect polarization with inclusion rotation, a novel insight into active matter dynamics.

Findings

Chiral gear-shaped inclusions show rectified rotation.

Inclusion rotation correlates with defect polarization.

Shape and boundary conditions influence inclusion dynamics.

Abstract

We investigate the dynamics of mobile inclusions embedded in 2D active nematics. The interplay between the inclusion shape, the boundary-induced nematic order, and the autonomous flow powers the inclusion motion. Disks and achiral gears exhibit unbiased rotational motion, but with distinct dynamics. In comparison, chiral gear-shaped inclusions exhibit long-term rectified rotation, which is correlated with dynamics and polarization of nearby +1/2 topological defects. The chirality of defect polarities and the active nematic texture around the inclusion correlate with the inclusion's instantaneous rotationr ate. Inclusions provide a promising tool for probing the rheological properties of active nematics and extracting ordered motion from the inherently chaotic motion of active nematics.