Complex nonlinear behavior in optically excited nematic liquid crystals

We present a study of the passage of a monochromatic, linearly polarized cw laser beam through a cell of homeotropically aligned nematic liquid crysta l at a slightly oblique angle. The light is polarized perpendicular to the plane of incidence. Experiments in this geometry have revealed the existenc e of complex, time-dependent dynamics of the director motion. We present a model for the director dynamics derived from the basic equations that shows both periodic and chaotic behavior at different light intensities as obser ved in the experiments. The model we derive exhibits a variety of complex b ehaviors, among them an uncommon route to chaos via gluing bifurcarions tha t has not yet been observed in any real physical system.