SiO₂ nanoparticles was synthesized by sol-gel method and polymer nanocomposites by solvo-casting method. XRD and SEM analysis have revealed the size, morphological structure and formation of SiO₂/PVA-PEG polymer nanocomposites. The presence of hydrogen bond between SiO₂ and PVA-PEG was proved with the help of Fourier Transform Infra Red Spectroscopy (FTIR). Further UV-Vis studies were used to find the optical band gap and linear refractive index. Third order nonlinear optical properties such as two photon absorption, nonlinear refractive index and third order nonlinear susceptibility was evaluated for the title compound using Z-scan method. The estimated nonlinear optical properties of title compound proved the appropriateness of the sample for optical applications.

中文翻译：

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Z-扫描法评估SiO2 / PVA-PEG纳米复合材料的三阶非线性光学性质

通过溶胶-凝胶法合成了SiO ₂纳米颗粒，通过溶剂浇铸法合成了聚合物纳米复合材料。XRD和SEM分析揭示了SiO ₂ / PVA-PEG聚合物纳米复合材料的尺寸，形态结构和形成。SiO ₂之间存在氢键傅里叶变换红外光谱（FTIR）证明了PVA-PEG。进一步的UV-Vis研究用于发现光学带隙和线性折射率。使用Z扫描法评估了标题化合物的三阶非线性光学性质，如两个光子吸收，非线性折射率和三阶非线性磁化率。估计的标题化合物的非线性光学性质证明了该样品适用于光学应用。