Nordahl Gregory, Jones Lewys, Christiansen Emil Frang, Hunnestad Kasper Aas, Nord Magnus
Department of Physics, Norwegian University of Science and Technology (NTNU), 7491 Trondheim, Norway.
School of Physics, Trinity College Dublin, Dublin 2, Ireland; Advanced Microscopy Laboratory, Centre for Research on Adaptive Nanostructures and Nanodevices (CRANN), Dublin 2, Ireland.
Ultramicroscopy. 2023 Jun;248:113715. doi: 10.1016/j.ultramic.2023.113715. Epub 2023 Mar 8.
Precession electron diffraction has in the past few decades become a powerful technique for structure solving, strain analysis, and orientation mapping, to name a few. One of the benefits of precessing the electron beam, is increased reciprocal space resolution, albeit at a loss of spatial resolution due to an effect referred to as 'probe wandering'. Here, a new methodology of precession path segmentation is presented to counteract this effect and increase the resolution in reconstructed virtual images from scanning precession electron diffraction data. By utilizing fast pixelated electron detector technology, multiple frames are recorded for each azimuthal rotation of the beam, allowing for the probe wandering to be corrected in post-acquisition processing. Not only is there an apparent increase in the resolution of the reconstructed images, but probe wandering due to instrument misalignment is reduced, potentially easing an already difficult alignment procedure.
在过去几十年中，进动电子衍射已成为一种强大的技术，可用于结构解析、应变分析和取向映射等。使电子束进动的一个好处是增加了倒易空间分辨率，尽管由于所谓的“探针漂移”效应会损失空间分辨率。在此，提出了一种新的进动路径分割方法，以抵消这种效应并提高从扫描进动电子衍射数据重建的虚拟图像的分辨率。通过利用快速像素化电子探测器技术，在电子束每次方位角旋转时记录多帧，从而允许在采集后处理中校正探针漂移。不仅重建图像的分辨率明显提高，而且由于仪器未对准导致的探针漂移也减少了，这可能会简化本就困难的对准程序。
