Temperature and Polarization Dependence of Transient Gratings in Azo-Dye-Doped Liquid Crystals

holography technique involving various polarizations of excitation and probe beams has been employed to identify the strong asymmetry of excitation and diffraction in the guest-host system. In this paper, we report the temporal profiles of diffraction efficiency for transient gratings and their temperature and polarization dependences in azo-dye-doped liquid crystals. The dynamics of molecular reorientation phenomena in transient gratings is investigated by analyzing the buildup time of the diffraction maximum and diffractive decay. The study of the polarization dependence of the first-order diffraction efficiency and its corresponding temperature effect allows us to understand the underlying mechanism of laser-induced transient gratings. 2. Experimental