Developement of nonlinear photonic materials by using semiconductor quantum dot-photopolymer composites

本文研究了光聚合半导体CdSe量子点-光聚合物复合材料（QDPCs）的三阶和高阶光学非线性，以及具有全息形成的光子晶格结构的QDPCs中的非线性光学效应。我们已经证明CdSe量子点可以均匀地分散在高达7 vol.%的光聚合物中。我们测量了均匀固化的QDPC薄膜的三阶和五阶非线性折射率和饱和吸收的增加。我们还在简并的多波混合结构中观察到了高阶自衍射现象，并在QDPC薄膜中实现了全息形成的布拉格光栅的非线性布拉格衍射。此外，我们还对全息曝光下QDPCs的相变动力学进行了理论分析，从而定量地阐明了Bragg光栅形成的动力学。

We have investigated enhanced third- and high-order optical nonlinearities in photopolymerizable semiconductor CdSe quantum dot-photopolymer composites (QDPCs) as well as the nonlinear optical effects in QDPCs with the holographically formed photonic lattice structure. We have showed that CdSe quantum dots can be uniformly dispersed as high as 7 vol.% in photopolymer. We have measured the increased third- and fifth-order nonlinear refraction and saturable absorption in uniformly cured QDPC films. We have also observed high-order self-diffraction phenomena in a degenerate multi-wave mixing configuration and achieved nonlinear Bragg diffraction from a holographically formed Bragg grating in a QDPC film. In addition, we have performed a theoretical analysis of the phase transition dynamics in QDPCs under holographic exposure, by which the dynamics of Bragg grating formation have been clarified quantitatively.