Domain Formation and Lehmann Effect of a Cholesteric Liquid Crystal Contacting with Its Isotropic Phase by a Flat Interface

Abstract

Cholesteric liquid crystals, which have an intrinsic length scale, exhibit a variety of orientational structures depending on the size of the system and the interface anchoring. We found that cholesteric liquid crystals contacting with a flat interface with their isotropic phase form spiral finger-textured domains with a specific thickness. In addition, we found that the domains exhibit a steady unidirectional rotation when a temperature gradient perpendicular to the interface is applied. This phenomenon seems to be driven by the thermomechanical coupling between the temperature gradient and the rotation, which originates from the chirality of cholesteric liquid crystals.