New Optical Materials based on Rare Earth Doped Oxyfluoride Glasses and Ceramics: Structural Studies by Magnetic Resonance Methods

新型高光学质量稀土离子掺杂晶体、玻璃和陶瓷作为固体激光材料的发展是当前材料研究的一个活跃领域。为了便于设计具有最佳发射性能的材料，原子一级的详细结构信息是必不可少的，这些信息涉及稀土离子的局部成键环境(位置)、它们的次近邻配位球、它们的局部聚集程度以及在复合材料中不同微相或纳米相上的分布。在这个项目中，我们寻求在结构的基础上对这类材料系统的光谱和光物理性质有一个基本的了解，结合核磁共振和电子顺磁共振作为结构工具。所研究的系统是基于氟铝酸盐、氟磷酸盐和氟化碲酸盐组成的玻璃。为此，将开发一种全面的固态核磁共振和EPR策略，并将其用于表征发射体离子的局部环境。通过这些方法获得的结构信息及其与光学材料性能的关系将对开发新的高功率激光材料设计策略具有重要意义。

The development of novel high optical quality rare earth ion doped crystals, glasses and ceramics as solid state laser materials presents an active area of current materials research. To facilitate the design of materials with optimized emission properties, detailed structural information at the atomic level is essential, regarding the local bonding environment (siting) of the rare earth ions, their second-nearest coordination sphere, and their extent of local clustering, as well as the distribution over separate micro- or nanophases in composite materials. In this project, we seek a fundamental understanding of the spectroscopic and photophysical properties of such material systems on a structural basis, combining NMR and EPR as structural tools. The systems studied are glasses based on fluoroaluminate, fluoride phosphate and fluoride tellurite compositions. To this end a comprehensive solid state NMR and EPR strategy will be developed and applied for characterizing the local environment of the emitter ions. The structural information obtained by these approaches and its correlation with the optical materials properties will be important for developing new design strategies for high power laser materials.