论文部分内容阅读
用胶体法制备了表面分别修饰六偏磷酸钠 (HMP)和 2 ,2’ 联吡啶 (BPy)的Ag2 S纳米微粒。通过背向简并四波混频实验装置对它们在单光子非共振区域的三阶光学非线性进行了实验研究 ,分别测量了两种Ag2 S纳米微粒在它们超滤液中三阶非线性极化率 χ( 3 ) 随浓度的变化 ,并拟合得到了两种纳米微粒的三阶非线性极化率。实验结果表明 ,双光子共振增强是实验中非线性极化的主要过程 ,同时实验结果也表明了局域场效应对单光子非共振三阶非线性极化率的增强作用
Ag2S nanoparticles with surface modified sodium hexametaphosphate (HMP) and 2,2 ’bipyridine (BPy) were prepared by colloidal method. The third-order optical nonlinearity in single-photon nonresonance region was experimentally studied by the degenerate four-wave mixing experimental device. The effects of the two Ag2S nanoparticles on the third-order nonlinearity The third-order nonlinear polarizability of the two kinds of nanoparticles was fitted by the change of the rate χ (3) with the concentration. Experimental results show that the enhancement of two-photon resonance is the main process of nonlinear polarization in the experiment. The experimental results also show that the local field effect enhances the non-linear third-order nonlinear polarizability