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arXiv · 2301.05787

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

Sattvic Ray·Jie Zhang·Zvonimir Dogic
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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.

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Sattvic Ray, Jie Zhang, Zvonimir Dogic. 2023-01-13. Rectified Rotational Dynamics of Mobile Inclusions in Two-Dimensional Active Nematics. https://doi.org/10.1103/physrevlett.130.238301

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