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arXiv · 1605.06472

Reconfigurable swarms of colloidal particles electrophoretically drivenin nematic liquid crystals

Sergi Hernàndez-Navarro·Pietro Tierno·Jordi Ignés-Mullol·Francesc Sagués
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Abstract

We present experiments where anisometric colloidal microparticles dispersed in a nematic liquid crystal cell with homeotropic anchoring conditions are dynamically assembled by means of liquid-crystal-enabled electrophoresis (LCEEP) using an AC electric field perpendicular to the confining plates. A nematic host with negative dielectric anisotropy leads to a driving force parallel to the cell plates. We take advantage of the resulting gliding anchoring conditions and the degeneracy in the direction of particle motion to design reconfigurable trajectories using a photosensitive anchoring layer (azosilane self-assembled monolayer), as the particle trajectory follows the local director orientation.

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Sergi Hernàndez-Navarro, Pietro Tierno, Jordi Ignés-Mullol, Francesc Sagués. 2016-05-20. Reconfigurable swarms of colloidal particles electrophoretically drivenin nematic liquid crystals. https://arxiv.org/abs/1605.06472

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