关于磁分相对比成像对前行的影响
Gregory Nordahl1, Sivert Dagenborg1, Andrea D'Alessio2
1Department of Physics, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway.
概括
在低放大度的STEM-DPC成像中,电子束偏移显示出有限的好处. 分段显示相位变化平滑的配置文件,但非圆形的路径导致磁场成像中的工件.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 显微镜的使用方法
背景情况:
- 在扫描传输电子显微镜 (STEM) 中的相差相对比 (DPC) 成像面临着将衍射效应与相对比分开的挑战.
- 电子束偏移已经被用来通过使直射束均化来改善电磁场成像.
- 低放大 (LM) STEM-DPC成像受到探针形成镜头偏差的阻碍,限制了小的前置角度.
研究的目的:
- 为了研究在低放大STEM-DPC成像中前行路径细分的有效性.
- 分析前置对成像磁性材料 (如LSMO和FeAl薄膜) 的影响.
- 了解光束相位转移和前cession路径几何对DPC信号的贡献.
主要方法:
- 在LM-STEM预处理扫描中应用前cession路径细分.
- 甲 (LSMO) 和FeAl薄膜样本的成像.
- 分析DPC诱导配置平滑和重建文物.
主要成果:
- 在LM-STEM-DPC成像中,电子束偏移的好处不如以前所认为的那么大.
- 前置诱导的光束相位转移显著有助于平滑DPC感应配置文件.
- 发现前行轨道是非圆形的,导致在重建的感应图中出现条纹文物.
结论:
- 在LM-STEM-DPC中的前行路径细分揭示了相位变化是轮平滑的一个主要因素.
- 非圆形的前进路径引入了文物,限制了这种模式中磁场重建的准确性.
- 为了在LM-STEM中获得可靠的磁性DPC成像,需要进一步优化前进策略.
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