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Curvature controlled defect dynamics in topological active nematics.

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.

SUBMITTER: Alaimo F

PROVIDER: S-EPMC5507919 | biostudies-literature | 2017 Jul

REPOSITORIES: biostudies-literature

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Curvature controlled defect dynamics in topological active nematics.

Alaimo Francesco F Köhler Christian C Voigt Axel A

Scientific reports 20170712 1

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 configura ...[more]

PMID: 28701792

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