Ognysta U. The elastic interaction of colloidal particles in nematic liquid crystals

The thesis deals with behavior and interaction through director distortions of micron-sized spherical particles in nematic colloidal systems. An interaction between colloidal particles and director field locally distorted by optical tweezers was investigated. The elastic interaction between colloidal particles with dipolar symmetry of director field and a focused laser beam reveals a Coulomb-like character. Ordered colloidal systems at the free surface of a liquid crystal, their behavior under action of external electric and magnetic fields as well as pairwise elastic interaction of the particles were investigated. Elastic interaction of colloidal particles with dipolar and quadrupolar symmetry of the director field in nematic liquid crystal was experimentally determined. For the first time, two-dimensional mixed dipolar-quadrupolar colloidal crystals were built.