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Structure of smectic defect cores: an X-ray study of 8CB liquid crystal ultra-thin films

Jean-Philippe Michel·Emmanuelle Lacaze·Michel Goldmann·Marc Gailhanou·Marc De Boissieu·Michel Alba
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Abstract

We study the structure of very thin liquid crystal films frustrated by antagonistic anchorings in the smectic phase. In a cylindrical geometry, the structure is dominated by the defects for film thicknesses smaller than 150 nm and the detailed topology of the defects cores can be revealed by x-ray diffraction. They appear to be split in half tube-shaped Rotating Grain Boundaries (RGB). We determine the RGB spatial extension and evaluate its energy per unit line. Both are significantly larger than the ones usually proposed in the literature

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Jean-Philippe Michel, Emmanuelle Lacaze, Michel Goldmann, Marc Gailhanou, Marc De Boissieu, Michel Alba. 2005-10-26. Structure of smectic defect cores: an X-ray study of 8CB liquid crystal ultra-thin films. https://doi.org/10.1103/physrevlett.96.027803

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