Dipolar orientational relaxation in guest/host amorphous polymer probed by second harmonic generation
Dipolar orientational relaxation in guest/host amorphous polymer probed by second harmonic generation
复制标题
通过二次谐波产生探测客体/主体无定形聚合物中的偶极取向弛豫
DOI：
10.1021/ma00060a007
复制
发表时间：
1993
期刊：
影响因子：
5.5
通讯作者：
C. H. Wang
中科院分区：
文献类型：
--
作者：
T. Goodson;C. H. Wang
翻译后摘要：分散在无定形聚合物基质中的非线性光学发色团的二次谐波信号的衰减进行了研究。衰减曲线可以拟合到Kohrausch-Williams-Watts（KWW）拉伸指数函数或双指数函数。双指数拟合更好地描述了接触电极极化的非晶NLO聚合物膜的二阶非线性光学极化率的衰减。弛豫曲线的快衰减分量是由于非线性光学偶极子的重取向和三阶光学非线性的综合作用。慢衰减是由于NLO偶极子的旋转扩散。旋转弛豫时间的温度依赖性被发现遵循Vogel-Fulcher-Tamman方程。
Abstract : The decay of the second harmonic signal of a nonlinear optical chromophore dispersed in an amorphous polymer matrix is investigated. The decay curve can be fit either to the Kohrausch-Williams-Watts (KWW) stretched exponential function or to a bi-exponential function. The bi-exponential fit gives a better description of the decay of the second order nonlinear optical susceptibility of the contact electrode poled amorphous NLO polymer film. The fast decay component of the relaxation curve is attributed to the combined effect of reorientation of NLO dipole and the third order optical nonlinearity. The slow decay is due to the rotational diffusion of the NLO dipole. The temperature dependence of the rotational relaxation time is found to follow the Vogel-Fulcher-Tamman equation.