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Phase behavior of a nematic liquid crystal in contact with a chemically and geometrically structured substrate

L. Harnau·S. Kondrat·A. Poniewierski
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Abstract

A nematic liquid crystal in contact with a grating surface possessing an alternating stripe pattern of locally homeotropic and planar anchoring is studied within the Frank--Oseen model. The combination of both chemical and geometrical surface pattern leads to rich phase diagrams, involving a homeotropic, a planar, and a tilted nematic texture. The effect of the groove depth and the anchoring strengths on the location and the order of phase transitions between different nematic textures is studied. A zenithally bistable nematic device is investigated by confining a nematic liquid crystal between the patterned grating surface and a flat substrate with strong homeotropic anchoring.

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L. Harnau, S. Kondrat, A. Poniewierski. 2005-03-18. Phase behavior of a nematic liquid crystal in contact with a chemically and geometrically structured substrate. https://doi.org/10.1103/physreve.72.011701

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