The piezo-induced second-order nonlinear optical effect in polyvinyl alcohol/YAB:Cr nanocomposites
The piezo-induced second-order nonlinear optical effect in polyvinyl alcohol/YAB:Cr nanocomposites
复制标题
聚乙烯醇/YAB:Cr纳米复合材料中压电引起的二阶非线性光学效应
DOI：
10.1088/0957-4484/15/9/002
复制
发表时间：
2004
期刊：
影响因子：
3.5
通讯作者：
I. Kityk
中科院分区：
文献类型：
--
作者：
A. Majchrowski;J. Ebothé;B. Sahraoui;I. Kityk
在掺杂了尺寸为10 - 40纳米的YAB:Cr纳米微晶的聚乙烯醇光聚合物中，研究了压电诱导的皮秒非线性光学效应。研究了二次谐波产生（SHG）与高达20吉帕的单轴施加机械应力的关系。在包含压电诱导声子的五阶非线性光学极化率框架内解释了所观察到的现象，压电诱导声子有利于所观察到的非中心对称电子 - 声子非谐性。通过有效二阶极化率的尺寸依赖行为，证明了纳米晶限域效应在所观察现象中的重要作用。对所观察到的现象进行了量子化学和分子动力学模拟。
Piezo-induced picosecond nonlinear optical effects are investigated in polyvinyl alcohol photopolymer doped by YAB:Cr nanocrystallites of 10?40?nm size. The second harmonic generation (SHG) is studied versus the applied uniaxial mechanical stress up to 20?GPa. The observed phenomena are explained within a framework of fifth-order nonlinear optical susceptibilities with the inclusion of piezo-induced phonons, which favour the observed non-centrosymmetric electron?phonon anharmonicity. The substantial role of the nanocrystalline confinement effect in the observed phenomenon is demonstrated through the size-dependent behaviour of the effective second-order susceptibility. Quantum chemical and molecular dynamics simulations of the observed phenomenon are carried out.