Phase velocity evaluation of elastic wave propagating in nematic liquid crystal cell

Abstract

Propagation characteristics of elastic waves in a liquid crystal cell are described from the view points of numerical analysis. A periodical stripe domain pattern is induced by an interaction between the elastic wave and nematic liquid crystal and is observable via a polarized microscope. The propagation characteristics in the solid/liquid/solid trilayer are related to the material constants. The 0th mode is strongly dependent on the conditions of the liquid crystal layer, while the 1st mode is almost independent of the liquid phase condition. The 0th mode phase velocity is estimated from the period of the observed stripe domian. The evaluated obtained results in nematic liquid crystal MBBA ((4'-Methoxybenzylidene-4-n-butylaniline) are in good consistency with the numerical analysis. This method has the advantage of the simplicity in evaluation and need very small amount of nematic liquid crystal.