Anchoring effects on the propagation of modes in a blue phase cylindrical fibre

Abstract

ABSTRACT We study the transverse normal linear propagating modes within a cylindrical wave guide filled with a blue-phase liquid crystal, which is subjected to the cladding by means of soft anchoring boundary conditions. The axis of the two dimensional helical structure of the blue phase is taken parallel to the cylindrical wave guide axis. We establish the coupled governing equations consisting of the electromagnetic Maxwell’s equations in the presence of a blue phase and the equilibrium equations for the blue-phase texture resulting from the minimisation of both, the bulk and surface free energy. By assuming a low intensity electromagnetic field, we decouple the texture equation and solve it to obtain blue-phase configurations; parameterised for different anchoring energies from which calculate the band structure and electromagnetic fields associated to these textures. We find that the number of propagating modes in the blue-phase cored waveguide depends on the anchoring strength.