Chirality-induced helical self-propulsion of cholesteric liquid crystal droplets

Abstract

We report the first experimental realization of a chiral artificial microswimmer exhibiting the helical motion. We found that a cholesteric liquid crystal droplet with a helical director field swims in a helical path driven by the Marangoni flow in an aqueous surfactant solution. We confirmed that the handedness of the droplet determines that of the helical path. This result strongly suggests that the helical motion is originated from the chirality of the cholesteric liquid crystal. To study the mechanism of the emergence of the helical motion, we propose a coupled time-evolution equations in terms of a velocity, an angular velocity and a tensor variable representing the symmetry of the helical director field of the droplet. Our model shows that the chiral coupling terms between the velocity and the angular velocity play a crucial role in the emergence of the helical swimming of the droplet.

arXiv comment5 pages, 4 figures

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Cited by in corpus (6)

• Memory-induced transition from a persistent random walk to circular motion for achiral microswimmers
• Dynamics of a chiral swimmer sedimenting on a flat plate
• Active cholesterics: odder than odd elasticity
• Hydrodynamics of chiral squirmers
• Gliding filament system giving both orientational order and clusters in collective motion
• Viscotaxis of chiral microswimmer in viscosity gradients