聚对苯撑亚乙烯/SiO2块状溶胶-凝胶非线性光学材料的研究

我们制作了一种由π－共轭聚合物聚对苯撑亚乙烯（PPV）均匀掺杂SiO2的块状溶胶－凝胶材料，该材料具有良好的光学品质和光学加工性能。通过扫描隧道显微镜（STM），紫外－可见吸收光谱和付氏红外光谱（FTIR）等方法研究了它的非线性光学特性。在对材料进行的光学两波耦合实验中，观察到了非对称能量耦合现象，并对此进行了分析。从吸光度和两波耦合衍射效率两方面对比了含PMMA和不含PMMA的两批不同掺杂浓度的PPV／SiO2 sol-gel材料的不同特性。

Study on Nonlinearly Optical Properties of PPV/SiO2 Sol-gel Bulk Material

A piece of novel optical storage material-PPV/SiO 2 sol-gel material has been produced in the following steps: (1) PPV precursor has been synthesized by Wessling method; (2) PPV/SiO 2 sol-gel complex material has been prepared by mixing silicon sol and PPV precursor and then through the process of gelation, vaporization and heating; and (3) the material has been doped with the polymer (methyl methacrylate) to improve its characteristics. STM, UV and FT-IR have been used to analyze the physical properties of the composite material. The STM photography of SiO 2 sol-gel shows porous structure with size of about 100nm. The UV and FT-IR absorption spectra show that PPV has been produced in the complex system after the heating process. In the two-beam coupling experiment, asymmetric energy transfer has been observed. While the material was irradiated by two laser beams of equal intensity, one beam increased and the other decreased at the same time and then got to saturation. A photorefraction-like mode has been used to explain the phenomena. The dependence of absorption and diffraction efficiency on PPV concentration has also been investigated. The results indicate that both of them increase with concentration with PPV. The absorption and diffraction efficiency are also influenced by doping or un-doping PMMA.