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Nematic liquid crystal in a tube: The Fréedericksz transition
Phys. Rev. E 48, R2366(R) – Published 1 October, 1993
DOI: https://doi.org/10.1103/PhysRevE.48.R2366
Abstract
We study the configurations of a nematic liquid crystal confined between two concentric cylinders, of radii and ρ>, with homeotropic anchoring conditions at the walls. For ρ<=exp[π √(/) ] the director is purely radial, while for ρ> the director ‘‘escapes into the third dimension’’ and gains an axial component. This represents a geometrically induced Fréedericksz-like transition. When combined with a radial field and a nematic liquid crystal with a dielectric anisotropy ->0, the critical voltage of the Fréedericksz transition can be made arbitrarily small. This is of interest for liquid-crystal displays, since in the planar geometry the critical voltage is a material constant. A related temperature-induced Fréedericksz-like transition is expected in semiflexible nematic polymers.
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