Study of waveguides based in liquid crystals interfaces

We study an air-glass interface with an additional thin bilayer consisting of a cholesteric liquid crystal doped with silver nanospheres, and a silver thin film.

We propose a theoretical model for the propagation of electromagnetic waves through the liquid crystal layer part and use theMarcuvitz-Schwinger form of the Maxwell equations to show the existence of modes that propagate along the interface with negligible attenuation (i.e. approximate surface modes). The wave profile is computed by a combination of analytical and numerical methods. The presence of the cholesteric liquid crystal introduces inhomogeneity and anisotropy in the problem,

and the wave vector and frequency required for surface modes are found by solving a nonlinear system. Propagating surface modes are shown to occur at specific frequencies that belong to the optical spectrum.The dependence of the surface wave parameters on the liquid crystal parameters can be useful for sensing stimuli that modify the liquid crystal parameters.