飞秒激光所致金纳米粒子析出的玻璃非线性吸收

依据Z-scan技术，使用波长532nm的纳秒脉冲，研究了通过聚焦的飞秒脉冲诱导并辅以热处理得到的金纳米粒子析出的玻璃的非线性吸收．观察到金纳米粒子析出的玻璃具有饱和吸收特性．根据局域场效应，对实验结果拟合，得到在接近表面等离子体共振激发情况下，金纳米粒子三阶极化率虚部分别为Imχm^(3)=5．7×10^-7esu．玻璃样品中金纳米粒子的非线性响应主要起源于热电子贡献。

We have investigated, by using Z-scan technique with ns pulses at 532nm, the nonlinear absorptions of Au-nanoparticles-precipitated glasses obtained by irradiation of focused femtosecond pulses with the help of heat treatment. We observed the saturable absorption behavior in Au-nanoparticles-precipitated glasses. We obtain, by fitting to the experimental results I in the light of the local field effect near the surface plasmon resonance, Imx(m)((3)) = 5.7 x 10(-7) esu for the imaginary parts of the third-order susceptibilities for Au nanoparticles. The nonlinear response of Au nanoparticles in the glass samples arises mainly from the hot electron contribution.