CHIRAL NEMATIC DROPLETS WITH TANGENTIAL ANCHORING AND NEGATIVE DIELECTRIC ANISOTROPY IN AN ELECTRIC-FIELD

Model structures for the droplets of chiral nematic (cholesteric) liquid crystals with negative dielectric anisotropy exposed to the external electric field are developed. For tangential anchoring with no preferred direction a field induced transformation from structures with spherical chiral nematic surfaces via intermediate structures with ellipsoidal surfaces to planar structures is described. Two different spherical structures corresponding to defect lines with strength 1 and 2 are taken as the initial states. The number, type, and shape of χ disclination lines which occur in such systems are explained in detail. © 1995 The American Physical Society.