Determining the Anchoring Strength of a Capillary Using Topological Defects

Randall D. Kamien; Thomas R. Powers

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arXiv · cond-mat/9612169

Determining the Anchoring Strength of a Capillary Using Topological Defects

Randall D. Kamien·Thomas R. Powers

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Abstract

We consider a smectic-A* in a capillary with surface anchoring that favors parallel alignment. If the bulk phase of the smectic is the standard twist-grain-boundary phase of chiral smectics, then there will be a critical radius below which the smectic will not have any topological defects. Above this radius a single screw dislocation in the center of the capillary will be favored. Along with surface anchoring, a magnetic field will also suppress the formation of a screw dislocation. In this note, we calculate the critical field at which a defect is energetically preferred as a function of the surface anchoring strength and the capillary radius. Experiments at a few different radii could thus determine the anchoring strength.

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BibTeX RIS

Randall D. Kamien, Thomas R. Powers. 1997-02-03. Determining the Anchoring Strength of a Capillary Using Topological Defects. https://arxiv.org/abs/cond-mat/9612169

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