Applied Nanophotonics, Liquid Crystals and Biomedical Optics

The switching behavior of ferroelectric liquid crystals (FLCs) is studied both experimentally and theoretically. Experimentally the electro-optic response of multiwavelength-thick FLC cells revealed transient peak and dip characteristics. This behavior could not be explained at all according to the standard picture of a switchable birefringent plate, nor according to transient light scattering associated with ferroelectric domain reversal. Solutions of a numerical model of the FLC electric and elastic torques, which results in the sine-Gordon equation, showed the propagation of kink-antikink pair solitons. The nonuniform director structures corresponding to these solitons are sufficient to explain the experimental behavior of the transient electro-optic response with the wavelength, the field, and the polarizer-cell-analyzer orientation. The electro-optic response is found to be highly sensitive to the fixed boundary dipole orientations.