The photorefractivity of 14 ferroelectric liquid crystals (FLCs) mixed with a photoconductive compound was investigated by two-beam coupling experiments. The influence of the properties of low-molecular-weight FLCs on the photorefractive effect was examined, and it was found that the photorefractive two-beam coupling gain coefficients and the refractive index grating formation time are strongly dependent on the properties of FLCs. The effects of the magnitude of the spontaneous polarization, the viscosity, and the homogeneity of the surface-stabilized state on the photorefractivities of FLCs are discussed based on these findings.

The photorefractivity of a ferroelectric liquid crystal (FLC) mixed with a photoconductive compound was investigated in detail. FLCs are anisotropic media, so that laser beam incidence conditions strongly affect the formation of the refractive index grating. Effects of intersection angles of the laser beams, sample angle, sample rotation angle, sample thickness, and polarization of the laser beams on the photorefractivity of FLCs were examined.

The formation of dynamic holograms based on the spatial modulation of the molecular motions of ferroelectric liquid crystals (FLCs) was demonstrated. The consecutive rotational switching motion of FLC molecules under an alternating electric field was modulated by the photoinduced additional electric field built at the interference fringe. This spatially periodic difference in molecular motions of an FLC was confirmed to work as a diffraction grating. Since the motion-mode hologram is stable and the response is very fast when compared to photorefractive polymers, the motion-mode hologram appears to be promising for various photonic applications.

The photorefractive properties of mixtures of a ferroelectric liquid crystal and a photoconductive polymer were investigated by two-beam coupling experiments. A photorefractive effect based on reorientation of spontaneous polarization vector was induced in these mixtures. Asymmetric energy exchange was observed, and gain coefficients of 20-50 cm -1 were obtained. The dependences of the gain coefficient on temperature and external electric field were examined.

The photorefractive effect of photoconductive-polymer-stabilized ferroelectric liquid crystals (FLCs) was investigated. A photoconductive acrylate monomer and an electron acceptor compound were mixed with an FLC, and the mixtures were photopolymerized in the ferroelectric phase. A photoconductive polymer network was formed in the FLC medium, and a polymer-stabilized FLC was obtained. The photorefractive effect was evaluated by a two-beam coupling experiment. A large gain coefficient was obtained in the polymer-stabilized FLCs.