Experimental and numerical study of properties of nematic liquid crystal waveguide structures

Abstract

Nematic liquid crystal optical waveguide structures were studied by the numeric simulation and experimentally. Two types of optical smoothly-irregular waveguide structures promising for application in telecommunications and control systems are studied by numerical simulation and experimentally: liquid thin waveguide lens and thin film generalised waveguide Luneburg lens. The dependence of attenuation coefficient (optical losses) of the waveguide modes and the effective sizes (correlation radii) of the quasi-stationary irregularities of the liquid-crystal layer on the linear polarization of the incident laser radiation and the presence of pulse-periodic electric field were experimentally observed. An estimate is made of the correlation radii of liquid-crystal waveguide quasi-stationary irregularities. The observed decrease in the attenuation coefficient of the waveguide modes and the effective sizes of irregularities in the liquid-crystal layer, when the external electric field is switched on, explained by the effect of the decrease in the fluctuations correlation radii of the local orientation of the molecules of the liquid crystal. The obtained results are undoubtedly important for further research of dynamic processes inside non stationary waveguide liquid crystal layers, both from the theoretical point of view for understanding kinetic processes in the liquid crystals, and with practical, - in the organization and carrying out suitable experimental researches.