The Domain Mode in Ferroelectric Liquid Crystals a Novel Electrooptical Process

Abstract

ABSTRACTNovel electrooptical effects in ferroelectric liquid crystals with high spontaneous polarization (Ps ) are observed. They are connected with the formation of a modulated distribution of the macroscopic dipole moments of smectic layers if going along the layer normal. The period (D) of this modulation (ferroelectric domains) near the electrode surfaces (DS) and in the bulk (DB) of a FLC-specimen can differ appreciably, depending on an applied external voltage. The main role of the value of the effective spontaneous polarization is established. A variuos number of domain structures and corresponding diffraction patterns are observed under variation of frequency and amplitude of the external electric field. A simple explanation of the new electrooptical responses is proposed on the basis of interference and incommensurability of bulk and surface domains.