Lin Hui-Chi, Tai Chen-Yu
Opt Express. 2019 Apr 15;27(8):11264-11272. doi: 10.1364/OE.27.011264.
A silica-nanoparticle-and-azo-dye-doped liquid crystal (LC) phase grating with multistable and dynamic modes based on photo- and nanoparticle-induced alignments was demonstrated. The photoalignment suppressed the electrophoretic movement of the silica nanoparticles in the hybrid aligned nematic (HAN) LC cell to maintain the vertical orientation of LCs during the electrical operation process by means of the azo dyes adsorbed on the silica networks in the homogeneously aligned side of the sample, and contributed two LC structures to form a grating. Through the excitation of a DC pulse with proper polarity and an AC voltage, the multistable and dynamic diffraction efficiencies of the grating were achieved, respectively, by electrophoretically controlled silica nanoparticles and the electrically controlled birefringence effect of LCs.
展示了一种基于光诱导和纳米颗粒诱导排列的具有多稳态和动态模式的二氧化硅纳米颗粒和偶氮染料掺杂液晶（LC）相位光栅。光取向抑制了混合取向向列相（HAN）液晶盒中二氧化硅纳米颗粒的电泳运动，通过吸附在样品均匀取向一侧二氧化硅网络上的偶氮染料，在电操作过程中保持液晶的垂直取向，并促成两种液晶结构形成光栅。通过施加具有适当极性的直流脉冲和交流电压，分别利用电泳控制的二氧化硅纳米颗粒和液晶的电控双折射效应，实现了光栅的多稳态和动态衍射效率。
