RUI: Microscopic Structure and Magnetism in Rare Earth Amorphous Alloys

PI建议主要利用穆斯堡尔效应，在大约0.05K到室温或更高的温度范围内研究稀土非晶态合金的局域结构和磁性。最初的实验将扩展到其他非磁性金属成分，如铝和镓，然后扩展到具有磁性过渡金属的更复杂的非晶态系统，这是有技术意义的。穆斯堡尔效应是一种能提供有关离子排列的角度信息和单个稀土离子的磁性信息的微观探测器，非常适合于这样的研究。在这里提出的温度范围内的实验将得到关于晶态电场参数、交换场和这些分布的信息，以便与各种非晶态结构模型进行比较，例如硬球的密集随机堆积或随机网络模型。这些结果有望对非晶态结构和磁性的发展领域做出重大贡献。预计拟议的研究还将对富兰克林和马歇尔学院物理系的教育环境产生重大影响，继续增加校园内积极的实验研究，继续与斯坦福大学合作，并与宾夕法尼亚大学和坦普尔大学接触。

The PI proposes to study the local structure and magnetic properties of rare earth amorphous alloys over a range of temperature from approximately .05K to room temperature or above, principally using the Mossbauer effect. The original experiments will be extended to other non-magnetic metal constituents such as aluminum and gallium, and then to the more complicated amorphous systems with the magnetic transition metals, which are of technological interest. As a microscopic probe yielding angular information about the arrangements of ions and magnetic information about individual rare earth ions, the Mossbauer effect is well suited for such studies. Experiments over the range of temperature proposed here will yield information about crystalline electric field parameters, exchange fields, and distributions of these, to be compared to various models of amorphous structure such as dense-random-packing-of- hard-spheres or random network models. These results are anticipated to make a significant contribution to the developing field of amorphous structure and magnetism. The proposed research is also expected to have a major impact on the educational environment of the Physics Department at Franklin and Marshall College by continuing the increased amount of active experimental research on campus, and by continuing the collaboration with Stanford University and contacts with the University of Pennsylvania and Temple University.