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arXiv · 1808.03492

Point Defects, Chirality and Singularity Theory in Cholesteric Liquid Crystal Droplets

Joseph Pollard·Gregor Posnjak·Gareth P. Alexander·Simon Copar·Igor Musevic
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Abstract

We develop a theory of point defects in cholesterics and textures in spherical droplets with normal anchoring. The local structure of chiral defects is described by singularity theory and a smectic-like gradient field establishing a nexus between cholesterics and smectics mediated by their defects. We identify the defects of degree $-2$ and $-3$ observed experimentally with the singularities $D_4^{-}$ and $T_{4,4,4}$, respectively. Radial point defects typical of nematics cannot be perturbed into chiral structures with a single handedness by general topological considerations. For the same reasons, the spherical surface frustrates the chirality in a surface boundary layer containing regions of both handedness.

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Joseph Pollard, Gregor Posnjak, Gareth P. Alexander, Simon Copar, Igor Musevic. 2018-08-10. Point Defects, Chirality and Singularity Theory in Cholesteric Liquid Crystal Droplets. https://doi.org/10.1103/physrevx.9.021004

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