A NONLINEAR-ANALYSIS OF THERMAL INSTABILITIES IN HOMEOTROPIC NEMATICS

This paper employs a nonlinear analysis of the continuum equations to investigate the onset of thermal instability in a layer of nematic liquid crystal confined between two infinite, horizontal flat plates in the presence of a vertical temperature gradient. The case is considered in which the anisotropic axis is initially uniformly aligned perpendicular to the plates. A perturbation method is used on the nonlinear equations to investigate the possible existence of finite amplitude disturbances close to the linear threshold. The nature of the bifurcation is established using a numerical method based on Chebyshev collocation. The investigation includes a study of the effect on the bifurcation produced by a uniform magnetic field applied vertically across the plates.