Collaborative Research: Structure-Property Relationships of Novel Rare Earth-Ultraphosphate Glasses

北达科他大学物理系（UND）和密苏里大学罗拉分校陶瓷工程系（UMR）之间的多学科合作将开发和表征具有有趣的光学和磁性能的新型稀土（RE）磷酸盐玻璃，使这些玻璃成为高能激光，光学和磁光传感器以及其他应用的候选材料。初步的结构研究表明，稀土配位环境对玻璃成分的依赖程度不同寻常，特别是对于含有少于25 mol%稀土氧化物的玻璃。稀土配位环境的改变对这些玻璃的物理和光学性能有显著影响。然而，这些性质和这些玻璃的原子结构之间的关系的确切性质尚不清楚。研究人员将利用x射线吸收光谱、高能x射线和中子衍射技术以及红外/拉曼光谱获得有关原子结构的详细信息，特别是RE离子的配位环境。研究小组也将研究其磁性。UMR的研究小组将利用最小化水和过渡金属污染的技术，制备光学活性玻璃（包括Nd-和er -磷酸组合物）和具有潜在大磁化率的玻璃（例如，镝-磷酸组合物）。光学特性，包括吸收光谱，荧光光谱和荧光寿命，也将在UMR表征。如上所述，上述新的稀土磷酸盐玻璃家族似乎是重要实际应用的潜在候选者，如高能激光，光学和磁光传感器。然而，计划开发此类应用的科学家和工程师需要更多关于这些玻璃的原子结构-性质关系的信息。本文所述的多学科项目旨在提供这一重要信息。该项目将汇集一组来自UND的理工科学生/教师和一组来自UMR的工科学生/教师，共同开展一项具有挑战性的研究项目。这样的跨学科研究机会是罕见的，特别是在学生层面，而且对所有参与的研究人员都非常有益。

A multi-disciplinary collaboration between the Physics Department at the University of North Dakota (UND) and the Ceramic Engineering Department at the University of Missouri-Rolla (UMR) will develop and characterize new rare earth (RE) phosphate glasses that possess interesting optical and magnetic properties which make these glasses candidates for high-energy lasers, optical- and magneto-optical sensors, and other applications. Preliminary structural studies indicate an unusual dependence of rare earth coordination environment on the glass composition, especially for glasses containing less than 25 mol% rare earth oxide. Changes in RE coordination environment of these glasses appear to have a significant effect on their physical and optical properties. However, the exact nature of the relationships between these properties and the atomic structure of these glasses is poorly understood. The researchers at UND will obtain detailed information about the atomic structure, especially the coordination environments of the RE ions, using X-ray absorption spectroscopy, high-energy X-ray and neutron diffraction techniques, and IR/Raman spectroscopy. The UND team will investigate the magnetic properties as well. The research team at UMR will prepare optically active glasses (including Nd- and Er-phosphate compositions) and glasses with potentially large magnetic susceptibilities (e.g., Dy-phosphate compositions) using techniques to minimize contamination by water and transition metals. Optical characteristics, including absorption spectra, fluorescence spectra and fluorescence lifetimes, will also be characterized at UMR. As mentioned above, the new family of rare earth phosphate glasses mentioned above appear to be a potential candidate for important practical applications such as high-energy lasers, optical- and magneto-optical sensors. However, scientists and engineers planning to develop such applications need additional information on the atomic structure-property relationships of these glasses. The multi-disciplinary project described herein is designed to provide this important information. This project will bring together a group of science students/faculty from UND and a group of engineering students/faculty from UMR to work on a challenging research project. Such cross-disciplinary research opportunities are rare, especially at the student level, and quite beneficial to all researchers involved.