Microscopic Dynamics in Metallic and Semiconducting Amorphous Systems Detected by NMR

9802101吴这是一个凝聚态物理研究项目，研究金属和半导体非晶系统的微观动力学，这些系统具有高度的局域有序性，即将形成纳米晶相。正在研究的材料包括新发现的锆钛铜镍铍大块金属玻璃，以及热丝辅助化学气相沉积制备的高度有序的氢化非晶硅。研究的主要工具是核磁共振，它在原子水平上探测结构动力学。令人感兴趣的是结构松弛和其他原子向平衡运动的速率，特别是在量热玻璃转变温度Tg以下的金属玻璃。氢在非晶硅中的扩散动力学是一个长期存在的问题，也将被解决。该项目中的材料具有重要的应用，包括微型机械和太阳能。这项研究涉及量子力学、计算机模拟以及电子学和低温物理方面的实验室技能。该项目在物理、材料科学、计算机模拟、实验技能以及与其他科学家的交流技能方面对本科生和研究生进行培训。这个凝聚态物理学的研究项目涉及金属和半导体非晶态系统中的原子级运动，这些系统处于冻结成纳米晶体固体的边缘。主要的实验工具是核磁共振，它特别适合于探测伴随着相行为的慢原子运动。正在研究的材料包括新发现的锆钛铜镍铍大块金属玻璃，以及热丝辅助化学气相沉积制备的高度有序的氢化非晶硅。这些材料具有重要的应用，包括微型机械和太阳能。这项研究涉及量子力学、计算机模拟以及电子学和低温物理方面的实验室技能。该项目在物理、材料科学、计算机模拟、实验技能以及与其他科学家的交流技能方面对本科生和研究生进行培训。***

9802101 Wu This is a condensed matter physics research project in microscopic dynamics in metallic and semiconducting amorphous systems with high degrees of local order that are on the verge of forming nanocrystalline phases. Materials being studied include a newly discovered zirconium-titanium-copper-nickel-beryllium bulk metallic glasses, as well as highly ordered hydrogenated amorphous silicon made by hot filament assisted chemical vapor deposition. The main tool of investigation is nuclear magnetic resonance (NMR) which probes structural dynamics at the atomic level. Of interest is the rate of structural relaxation and other atomic motion toward equilibrium, especially below the calorimetric glass transition temperature, Tg, in the metallic glass. The diffusion dynamics of hydrogen in amorphous silicon is a long standing problem that will also be addressed. The materials in this project have important applications including micromachines and solar energy. The research involves quantum mechanics, computer simulations and laboratory skills in electronics and low temperature physics. The project trains under graduate and graduate students in a range of techniques in physics, material science, computer simulation, experimental skills, and communication skills with other scientists. %%% This research project in condensed matter physics deals with atomic-level motion in metallic and semiconducting amorphous systems that are on the verge of "freezing" into nanocrystalline solids. The main experimental tool is nuclear magnetic resonance (NMR) which is particularly appropriate for detecting the slow atomic motions accompanying the phase behavior. Materials being studied include newly discovered zirconium-titanium-copper-nickel- beryllium bulk metallic glasses, as well as highly ordered hydrogenated amorphous silicon made by hot filament assi sted chemical vapor deposition. These materials have important applications including micromachines and solar energy. The research involves quantum mechanics, computer simulations and laboratory skills in electronics and low temperature physics. The project trains under graduate and graduate students in a range of techniques in physics, material science, computer simulations, experimental skills, and communication skills with other scientists. ***