On the Cholesteric-Nematic Phase-Change Transition in Layers with Homeotropically Orienting Surfaces

Abstract

Lattice-model calculations of the energies of surface director-configurations are presented. These configurations mediate between the homeotropic surface conditions and the bulk fingerprint texture of cholesteric layers. Their energy determines the asymptotic behaviour of the cholesteric-nematic threshold field in the limit of thick layers. The dependence of their energies on the elastic constant ratios could be brought into a simple scaling form. This form is in agreement with existing and newly presented measurements.