热诱导KDP晶体应力缺陷演化规律的超微观研究

项目名称： 热诱导KDP晶体应力缺陷演化规律的超微观研究

项目编号： No.U1330118

项目类型： 联合基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 车仁超

作者单位： 复旦大学

项目金额： 86万元

中文摘要： 激光热诱导产生的KDP晶体应力缺陷降低了激光损伤阈值和谐波转化能力。在原子层次深入理解KDP晶体中的应力缺陷的超微观结构，对于研究激光能量在KDP晶体中的吸收、累积和热转化机理十分重要，且是目前本领域急需的。为解决以上科学问题，本课题旨在探索发展一套对KDP晶体应力缺陷有效的、基于先进透射电镜技术的探测表征技术，并提出针对不同类型缺陷的表征方法。阐明KDP晶体应力缺陷影响谐波转换/光电性能的物理本质。从超微观结构本质出发，研究热诱导KDP晶体中微观应力缺陷，如位错等结构缺陷和杂质金属离子，对激光倍频输出、光电开关等功能器件的影响机制。综合利用基于透射电子显微学的各类先进技术：原位加热、三维重构、电子能量损失谱、电子全息，研究重频激光作用下KDP晶体中热应力微观缺陷的形成机制。深入研究缺陷的原子结构和杂质金属离子的化学成分及键合信息，尤其是缺陷类型、数量与密度对KDP晶体器件性能的演化规律。

中文关键词： 磷酸二氢钾晶体；透射电镜；原位低温；晶体缺陷；应变

英文摘要： The strain defects of KDP crystals induced by thermal effects of laser irradiation reduce the laser damage threshold and harmonic generation capability. It becomes very important to deeply understand the super-microstructure of strain defects of KDP crystals at atomic-scale, which is important to investigating the mechanism of absorption, accumulation and thermal transformation process of laser energy inside KDP crystal and is urgently needed in this field. To solve the above scientific issues, this project aims at establishing and developing a set of efficient characterization techniques based on advanced transmission electron microscope (TEM) techniques for strain defects of KDP crystal. Characterization methods targeting different types of KDP defects would be established. The physical essence of the influences of strain defects of KDP crystals on the harmonic generation power/photoelectric effect will be illustrated. From the super-microstructure point of view, the influence mechanism of the strain defects of KDP crystals, such as dislocation-related defects and impurity metallic ions, on the laser harmonic generation and photoelectric capability of KDP crystals will be studied. Based on the combined advanced TEM techniques, including in situ TEM heating, 3D-tomography reconstruction, electron energy loss sp

英文关键词： KDP crystal；transmission electron microscopy；in situ low temperature；crystal defect；strain