采用新型的热化学还原法,制备了银纳米颗粒掺杂的铋酸盐复合玻璃材料。利用紫外-可见吸收光谱观察到了银纳米颗粒表面等离子谐振(SPR)吸收的峰值位移特性,用拉曼光谱表征了引入银纳米颗粒后玻璃的结构变化。借助飞秒激光脉冲激发下的Z扫描与光克尔闸技术,在近红外波段下研究了材料的三阶非线性光学特性。研究结果表明银纳米颗粒铋酸盐复合材料有着亚皮秒级的非线性响应时间,并且其非线性折射率γ在纳米颗粒的热电子效应以及局部场效应的影响下,较基质玻璃最高可以提升29倍。
In the present paper, Ag nanoparticles embedded bismuthate glass composite was prepared by using a novel thermc~- chemical reduction method. Red shift of surface plasmon resonance (SPR) absorption of the Ag nanoparticles was observed by utilizing UV-visible absorption spectra. The Raman spectra evidenced the evolution of the structural units of the glass after intro- duction of Ag nanoparticles. Z-scan and optical Kerr shutter technique with femtosecond laser as excitation source was applied to investigate the third-order optical nonlinearities of the nanocomposite in near-infrared region. The results show that the silver bismuthate nanocomposite possesses Kerr response in scale of sub-picosecond, and its nonlinear refraction γ was dramatically increased up to 29 times under the influences of hot electron effect and local field effect.