Smectic-A structures in submicrometer cylindrical cavities

Model structures of a smectic-A liquid crystal confined to a long cylindrical cavity enforcing homeotropic surface anchoring are studied theoretically. The structures are obtained numerically through minimization of the Landau–de Gennes type free energy. We limit our discussion to cylinders with submicrometer radia. Five qualitatively different smectic-A configurations are proposed: the smectic-planar-radial, smectic-escaped-radial, chevron, bookshelf, and hybrid structures. Our analysis suggests that in the strong anchoring regime the smectic–escaped-radial structure is the most stable. For this structure relatively large temperature shifts of the nematic–smectic-A phase transition are expected. In the weak anchoring regime the chevron and bookshelf structures are found to be the most stable. We demonstrate that smectic elasticity can cause strong deviations from the preferred surface anchoring direction. © 1996 The American Physical Society.