Probing Light Atoms at Subnanometer Resolution: Realization of Scanning Transmission Electron Microscope Holography.
Probing Light Atoms at Subnanometer Resolution: Realization of Scanning Transmission Electron Microscope Holography.
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以亚纳米分辨率探测光原子：扫描透射电子显微镜全息术的实现。
DOI：
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发表时间：
2018
期刊：
影响因子：
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通讯作者：
B. McMorran
中科院分区：
文献类型：
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作者：
F. Yasin;Tyler R. Harvey;J. Chess;J. Pierce;C. Ophus;P. Ercius;B. McMorran
电子透明材料中轻元素的原子分辨率成像长期以来一直是一个挑战。例如，生物分子材料会被入射电子迅速改变。我们展示了一种扫描透射电子显微镜（STEM）技术，称为STEM全息，能够有效地分析光束敏感纳米材料的结构。STEM全息术通过与真空参考波的干涉来测量穿过样品的电子的绝对相位和振幅。我们使用一个分幅纳米制造光栅来制备聚焦在样品上的多个光束。我们配置后标本显微镜成像系统重叠的光束，形成干涉图案。我们记录并分析每个二维光栅扫描位置的图案，重建复杂的物波。作为演示，我们以2.4 μ m的分辨率在无定形碳基底上成像金纳米颗粒。与高角度环形暗场STEM相比，STEM全息提供了更高的碳对比度，同时保持了金原子晶格分辨率。
Atomic resolution imaging of light elements in electron-transparent materials has long been a challenge. Biomolecular materials, for example, are rapidly altered by incident electrons. We demonstrate a scanning transmission electron microscopy (STEM) technique, called STEM holography, capable of efficient structural analysis of beam-sensitive nanomaterials. STEM holography measures the absolute phase and amplitude of electrons passed through a specimen via interference with a vacuum reference wave. We use an amplitude-dividing nanofabricated grating to prepare multiple beams focused at the sample. We configure the postspecimen microscope imaging system to overlap the beams, forming an interference pattern. We record and analyze the pattern at each 2D-raster-scan-position, reconstructing the complex object wave. As a demonstration, we image gold nanoparticles on an amorphous carbon substrate at 2.4 Å resolution. STEM holography offers higher contrast of the carbon while maintaining gold atomic lattice resolution compared to high angle annular dark field STEM.
影响因子：
3
作者：
Ruskin, Adrian I.;Yu, Zhiheng;Grigorieff, Nikolaus
通讯作者：
Grigorieff, Nikolaus