Simulation of spatially resolved electron energy loss near-edge structure for scanning transmission electron microscopy.
Simulation of spatially resolved electron energy loss near-edge structure for scanning transmission electron microscopy.
复制标题
扫描透射电子显微镜的空间分辨电子能量损失近边缘结构的模拟。
DOI：
10.1103/physrevlett.109.246101
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发表时间：
2012
影响因子：
8.6
通讯作者：
S. Pantelides
中科院分区：
文献类型：
--
作者：
M. Prange;M. Oxley;M. Varela;S. Pennycook;S. Pantelides
像差校正扫描透射电子显微镜产生探针位置相关的能量损失近边缘结构（ELNES）测量，可能提供潜在电子状态的空间映射。然而，ELNES计算通常描述了在真空中传播的平面波的激发，忽略了电子探针在穿过样品时与局部电子环境的相互作用。在这里，我们报告了一种结合了全电子结构计算和聚焦光束在薄膜中的传播的方法。结果表明，只有使用这种方法的详细计算才能提供与观测到的探针位置相关ELNES变化的定量一致。
Aberration-corrected scanning transmission electron microscopy yields probe-position-dependent energy-loss near-edge structure (ELNES) measurements, potentially providing spatial mapping of the underlying electronic states. ELNES calculations, however, typically describe excitations by a plane wave traveling in vacuum, neglecting the interaction of the electron probe with the local electronic environment as it propagates through the specimen. Here, we report a methodology that combines a full electronic-structure calculation with propagation of a focused beam in a thin film. The results demonstrate that only a detailed calculation using this approach can provide quantitative agreement with observed variations in probe-position-dependent ELNES.