Curvature controlled defect dynamics in topological active nematics

Francesco Alaimo; Christian Köhler; Axel Voigt

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arXiv · 1703.03707

Curvature controlled defect dynamics in topological active nematics

Francesco Alaimo·Christian Köhler·Axel Voigt

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Abstract

We study the spatiotemporal patterns that emerge when an active nematic film is topologically constraint. These topological constraints allow to control the non-equilibrium dynamics of the active system. We consider ellipsoidal shapes for which the resulting defects are 1/2 disclinations and analyze the relation between their location and dynamics and local geometric properties of the ellipsoid. We highlight two dynamic modes: a tunable periodic state that oscillates between two defect configurations on a spherical shape and a tunable rotating state for oblate spheroids. We further demonstrate the relation between defects and high Gaussian curvature and umbilical points and point out limits for a coarse-grained description of defects as self-propelled particles.

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Francesco Alaimo, Christian Köhler, Axel Voigt. 2017-03-10. Curvature controlled defect dynamics in topological active nematics. https://arxiv.org/abs/1703.03707

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