Dynamical behavior of prewavy pattern near nematic-isotropic transition

We report new results about a type of electrohydrodynamic instability, the prewavy instability, in a homeotropic nematic liquid crystal in a high-frequency electric field. This instability is seen in the form of a series of bright and dark stripes in between two crossed polarizers. The stripe formation corresponds to the periodic modulation of the rotation angle of the director in the xy-plane with periodicity along the x-direction. The dynamical behavior of prewavy patterns near the nematic-isotropic transition is reported. We found that the isotropic phase, due to the Joule heating effect, starts to grow in the dark stripes, i.e., in the vicinity of in-plane rotation angle α = 0.