在无形和无形的电子关联显微镜的挑战
Dražen Radić1, Martin Peterlechner1, Katharina Spangenberg1
1Institute of Materials Physics, University of Münster, Wilhelm-Klemm-Str. 10, Münster, 48149 North Rhine-Westphalia, Germany.
概括
无形和的电子相关显微镜揭示了重要的实验文物. 该研究得出结论,结构变化主要是由电子束驱动的,而不是由于在可访问的温度下自我扩散.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 电子显微镜电子显微镜
背景情况:
- 在像 (a-Ge) 和 (a-Si) 这样的无形材料中研究自我扩散对于理解它们的特性至关重要.
- 电子相关显微镜为研究原子级动力学提供了一个潜在的途径.
研究的目的:
- 用电子相关显微镜研究无形和中的自我扩散.
- 识别和减轻影响现场测量的实验工件.
主要方法:
- 在传输电子显微镜的现场加热过程中获得倾斜的暗场图像.
- 分析强度自相关数据使用伸缩指数匹配来确定特征时间 (τKWW).
主要成果:
- 测量受到包括污染,结晶,喷和样品曲在内的工件的显著影响.
- 特征时间 (τKWW) 表现出空间异质性,可能是由于非ergodicity,文物或结构不均.
- 特性时间在很大程度上独立于温度,特别是在无形中.
结论:
- 实验文物严重限制了通过这种方法在无形和中自我扩散的研究.
- 观察到的结构重组主要是由电子束驱动的.
- 真正的扩散动力学在使用的回火温度下测量太慢.
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