激光热诱导PbS纳米微粒的自陷、衍射和自散焦现象  

Laser-heating-induced Self-trapping,Diffraction andSelf-defocusing from PbS Nanoparticles

作　　者：欧慧灵[1,2] 彭淑鸽[1,2] 韩俊鹤[1,2] 

机构地区：[1]东南大学物理系,南京210096 [2]河南大学物理系,开封475001

出　　处：《光散射学报》2004年第3期246-249,共4页The Journal of Light Scattering

摘　　要：用波长为488nm的氩离子激光与聚乙烯吡咯烷酮(PVP)修饰的PbS纳米微粒水溶胶作用,观察到了样品的自陷、衍射和自散焦现象,样品的折射率为负。测量了自陷阈值功率,计算了样品的非线性折射率n2。样品响应时间为11.86ms,且对488nm波长的光有吸收,说明样品的上述现象主要是由激光热诱导折射率的改变所引起的。We have used a cw Argon ion laser (λ=488nm)for the generation of self-trapping,diffraction and self-defocusing from PbS nanoparticles modified by PVP。The sample's nonlinear refractive index n_2 is negative, which can be determined is by measuring sample's critical power of self-trapping。Rise time of the sample is 11.86ms and there are absorption at 488nm wavelength, so laser-heating-induced changes of refractive index causes the phenomena mentioned above。

关 键 词：PbS纳米微粒 自陷 自散焦 激光热诱导折射率 非线性折射率 响应时间 

分 类 号：O657.39[理学—分析化学]