Optically induced orientational transitions in nematic liquid crystals with planar alignment.
A theoretical study of dynamical phenomena induced by linearly polarized light incident perpendicularly on a planar aligned nematic layer with the light intensity as the control parameter is reported. We find the threshold of the optically induced twist Fréedericksz transition as a function of the problem parameters. The critical light intensity was found substantially lower than predicted earlier by Santamato [Phys. Rev. A 36, 2389 (1987)]. We have demonstrated by a rigorous stability analysis that the bifurcation is stationary only for a thickness of the nematic layer smaller than a certain critical value and becomes a Hopf bifurcation in the opposite case. Above the Hopf bifurcation an oscillatory state appears. It becomes unstable at a secondary threshold through a heteroclinic bifurcation, and the director settles to a new stationary distorted state.
Krimer
Dmitry O
DO
Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Strasse 38, D-01187 Dresden, Germany.