Influence of Light Polarization on Reorientational Nonlinearity in Nematic Liquid Crystals

Nematic liquid crystals are characterized by a giant optical nonlinearity which has its origin in the molecular reorientational phenomenon. Uniqueness of this nonlinear mechanism causes that response of the medium is dependent on many conditions. Among various of circumstances, both an initial alignment of liquid crystal cell and geometry of the system is very important, but in this paper a significant role of light polarization in nonlinear effects observed in nematics is emphasized. Additionally, it is underlined that dependence on light polarization does not have only trivial aspect of initial conditions. More complex seems to be fact that due to the high optical anisotropy of the medium the state of light polarization is being changing on the way of beam propagation. As a consequence, the modifications of molecular orientation in the liquid crystal cell are strongly dependent upon light polarization. PACS numbers: 42.65.-k, 42.70.Df