Berkels Benjamin, Liebscher Christian H
AICES, RWTH Aachen University, Aachen, NRW, Germany.
Max-Planck-Institut für Eisenforschung, Düsseldorf, NRW, Germany.
Ultramicroscopy. 2019 Mar;198:49-57. doi: 10.1016/j.ultramic.2018.12.016. Epub 2018 Dec 24.
Aberration corrected scanning transmission electron microscopes (STEM) enable to determine local strain fields, composition and bonding states at atomic resolution. The precision to locate atomic columns is often obstructed by scan artifacts limiting the quantitative interpretation of STEM datasets. Here, a novel bias-corrected non-rigid registration approach is presented that compensates for fast and slow scan artifacts in STEM image series. The bias-correction is responsible for the correction of the slow scan artifacts and based on a explicit coupling of the deformations of the individual images in a series via a minimization of the average deformation. This allows to reduce fast scan noise in an image series and slow scan distortions simultaneously. The novel approach is tested on synthetic and experimental images and its implication on atomic resolution strain and elemental mapping is discussed.
像差校正扫描透射电子显微镜（STEM）能够在原子分辨率下确定局部应变场、成分和键合状态。定位原子列的精度常常受到扫描伪像的阻碍，从而限制了STEM数据集的定量解释。在此，提出了一种新颖的偏置校正非刚性配准方法，该方法可补偿STEM图像序列中的快速和慢速扫描伪像。偏置校正负责校正慢速扫描伪像，它基于通过最小化平均变形对序列中各个图像的变形进行显式耦合。这使得能够同时减少图像序列中的快速扫描噪声和慢速扫描失真。该新方法在合成图像和实验图像上进行了测试，并讨论了其对原子分辨率应变和元素映射的影响。
