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arXiv · 2201.09190

Defect-polymorphism controlled electrophoretic propulsion of anisometric microparticles in a nematic liquid crystal

Devika V S·Dinesh Kumar Sahu·Ravi Kumar Pujala·Surajit Dhara
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Abstract

Nontrivial shape of colloidal particles create complex elastic distortions and topological defects in liquid crystals and play a key role in governing their electrophoretic propulsion through the medium. Here, we report experimental results on defects and electrophoretic transport of anisometric (snowman-shaped) dielectric particles subjected to an alternating electric field perpendicular to the director in a nematic liquid crystal. We demonstrate that the shape asymmetry gives rise to defect-polymorphism by nucleating point or ring defects at multiple locations on the particle and controls the direction as well as the magnitude of the electrophoretic propulsion. Our findings unveil a novel degree of freedom in translocating microparticles in liquid crystals for applications in microfluidics, controlled transport and assembly.

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Devika V S, Dinesh Kumar Sahu, Ravi Kumar Pujala, Surajit Dhara. 2022-01-23. Defect-polymorphism controlled electrophoretic propulsion of anisometric microparticles in a nematic liquid crystal. https://doi.org/10.1103/physrevapplied.18.014030

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