纳米复合非线性光学材料的构筑及其激光自倍频机理研究

All-optical information processing that one optical signal can control another signal without any limiting remains a serious public concern all over the world. It is of great scientific interest and technological significance to develop nonlinear optical materials with high performance facing the challenge of all-optical information processing. Now, obtaining sizable nonlinear optical materials involves high-cost and lengthy processes. In this project, we demonstrate a facile and feasible route to the controllable synthesis of nonlinear optical nanocomposites with tunable self-frequency-doubling properties and explore its generation mechanism intensively. First, rare earth nanoparticles (NPs) with controllable compositions and crystal structures were synthesized with a simple lanthanide doping method. The NPs were then dispersed uniformly into the solid matrices of a kind of transparent polymer materials to prepare nonlinear optical polymer nanocomposites. The main objective of the current study is just to study self-frequency-doubling properties of nanocomposites, to elucidate the matching mechanism of laser and frequency doubling properties of nanocomposites, to reveal the influencing mechanism of the rare earth ions doping content to the self-frequency-doubling efficiency. In the last, the self-frequency-doubling performance of nanocomposites would also be carried out to give a useful enlightenment for the development of novel nonlinear optical materials for photonic devices.

众所周知，使用一束信号光控制另一束信号光传输的所谓“全光信息处理”技术正成为科学家的奋斗目标。面对全光信息技术的挑战，发展新型高性能非线性光学材料起着至关重要的作用。本项目针对当前激光自倍频材料制备过程中造价高、过程繁琐等问题，提出一种简单可行的构筑新型纳米复合非线性光学材料的思路，着重对其激光自倍频的产生机制进行探索。首先，利用稀土掺杂的方法制备晶体组成与结构可调的纳米粒子；然后，利用无色、透明，易于掺杂和加工成型的聚合物材料作为固体基质，稀土纳米粒子作为构筑单元，制备新型纳米复合非线性光学材料；系统研究纳米复合材料的激光自倍频性质及产生机理，阐明纳米复合材料的激光特性和倍频特性的匹配机理，揭示掺杂稀土离子对于纳米复合材料激光自倍频性能的影响机制。通过对上述激光自倍频纳米复合体系的研究，初步评价纳米复合材料的激光自倍频性能，进而为新型非线性光学器件的设计开发工作提供理论基础和技术支持。

本项目的研究不仅涉及微纳尺度材料的制备和表征，还涉及到物质、能量的输运及相关的物理化学过程，是物理、化学和材料科学等学科的交叉。本项目采用具有光电功能的基本的有机构筑单元、无机构筑单元和有机-无机构筑单元构建微纳体系，对它们非线性光学性能、光电性能、电化学发光性能等进行表征，探索这些材料在光电领域的潜在应用。利用液相自组装的方式制备得到具有非中心对称结构的无机纳米材料，并且详细讨论了这些材料的非线性光学性能。利用主客体掺杂策略构筑无机、有机-无机杂化光电微纳体系：提出一种层状自组装策略构筑具有良好光电性质的有机-无机层状钙钛矿微纳材料，探索功能化的有机组分与钙钛矿结构的无机金属卤化物之间的协同作用规律，着重对其光电性能的产生机制进行深入探索；首次提出少量稀土离子掺杂调控微纳材料结构与发光性能的观点。构建有机半导体微纳电化学发光传感器，系统地研究电化学发光机制，为开发新型光电材料提供有价值的理论依据和技术支持：首次发现活性材料的晶体结构对电化学发光性能的影响机制；基于分子响应的电化学发光性能，构建有机半导体纳米线电化学发光传感器逻辑门，首次实现电化学发光逻辑门的级联应用。利用液相合成策略成功构筑过渡金属基微纳体系，将其作为电极材料，构建能量存储器件，并探讨其构-效关系。