Abstract
We utilize time-resolved optical waveguide spectroscopy for studying dynamics of a nematic liquid crystal(LC), in paticular, transient molecular orientation in the presence of an applied electric field. The waveguide patterns obtained from this technique involve the whole information about anisotropic dielectric constants of the LC layer, which is successfully characterized by theoretical analysis. In this study, we employed a nematic LC, 5CB, and prepared this LC as an optical waveguide in which LC directors were parallel to the glass substrate and rubbing direction. A dc pulsed field was applied to this waveguide cell, resulting in the homogeneous-to-homeotropic transition. Analyzing the obtained time-resolved waveguide patterns by using Deuling's theory, we could determine the tilt angle profile of the 5CB molecule in the LC layer, showing that this method has a potential to clarify the dynamic behavior of LC molecules.
