Pennycook Timothy J, Yang Hao, Jones Lewys, Cabero Mariona, Rivera-Calzada Alberto, Leon Carlos, Varela Maria, Santamaria Jacobo, Nellist Peter D
EPSRC SuperSTEM Facility, Daresbury Laboratory, Warrington WA4 4AD, UK; Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK.
Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, UK.
Ultramicroscopy. 2017 Mar;174:27-34. doi: 10.1016/j.ultramic.2016.12.002. Epub 2016 Dec 5.
Electron energy loss spectroscopy in the scanning transmission electron microscope has long been used to perform elemental mapping but has not previously exhibited depth sensitivity. The key to depth resolution with optical sectioning is the transfer of sufficiently high lateral spatial frequencies. By performing spectrum imaging with atomic resolution we achieve nanometer scale depth resolution, enabling us to optically section an oxide heterostructure spectroscopically. Such 3D elemental mapping is sensitive to atomic scale changes in structure and composition and is more interpretable than Z-contrast imaging alone.
扫描透射电子显微镜中的电子能量损失谱长期以来一直用于进行元素映射，但此前并未表现出深度敏感性。光学切片实现深度分辨率的关键在于传递足够高的横向空间频率。通过进行原子分辨率的能谱成像，我们实现了纳米级的深度分辨率，从而能够对氧化物异质结构进行光谱光学切片。这种三维元素映射对结构和成分的原子尺度变化敏感，并且比单独的Z衬度成像更具可解释性。
