Accurate and Robust Calibration of the Uniform Affine Transformation Between Scan-Camera Coordinates for Atom-Resolved In-Focus 4D-STEM Datasets

Ning, Shoucong1,2; Xu, Wenhui3,4; Ma, Yinhang5,6; Loh, Leyi1; Pennycook, Timothy J.7; Zhou, Wu5,6; Zhang, Fucai3; Bosman, Michel1; Pennycook, Stephen J.5,6; He, Qian1; Loh, N. Duane2,8,9

2022-03-01

10.1017/S1431927622000320

MICROSCOPY AND MICROANALYSIS   影响因子和分区

1431-9276

1435-8115

Accurate geometrical calibration between the scan coordinates and the camera coordinates is critical in four-dimensional scanning transmission electron microscopy (4D-STEM) for both quantitative imaging and ptychographic reconstructions. For atomic-resolved, in-focus 4D-STEM datasets, we propose a hybrid method incorporating two sub-routines, namely a J-matrix method and a Fourier method, which can calibrate the uniform affine transformation between the scan-camera coordinates using raw data, without a priori knowledge of the crystal structure of the specimen. The hybrid method is found robust against scan distortions and residual probe aberrations. It is also effective even when defects are present in the specimen, or the specimen becomes relatively thick. We will demonstrate that a successful geometrical calibration with the hybrid method will lead to a more reliable recovery of both the specimen and the electron probe in a ptychographic reconstruction. We will also show that, although the elimination of local scan position errors still requires an iterative approach, the rate of convergence can be improved, and the residual errors can be further reduced if the hybrid method can be firstly applied for initial calibration. The code is made available as a simple-to-use tool to correct affine transformations of the scan-camera coordinates in 4D-STEM experiments.

4D-STEM atomic resolution calibration ptychography

SCI

英语

其他

NUS Early Career Research Award[R-154-000-B35-133] ; MOE's AcRF Tier 1[R-284-000-172-114] ; NRF CRP grant[NRF-CRP16-2015-05] ; National Research Foundation (NRF) Singapore, under its NRF Fellowship[NRF-NRFF11-2019-0002] ; Beijing Outstanding Young Scientist Program[BJJWZYJH01201914430039] ; National Natural Science Foundation of China[11775105,12074167] ; European Union's Horizon 2020 research and innovation programme from the European Research Council (ERC)[802123-HDEM]

Materials Science ; Microscopy

Materials Science, Multidisciplinary ; Microscopy

WOS:000767045700001

CAMBRIDGE UNIV PRESS

MATERIALS SCIENCE

Web of Science

1.Natl Univ Singapore, Dept Mat Sci & Engn, Singapore 117575, Singapore
2.Natl Univ Singapore, Ctr Bioimaging Sci, Singapore 117557, Singapore
3.Southern Univ Sci & Technol, Dept Elect & Elect Engn, Shenzhen 518055, Peoples R China
4.Harbin Inst Technol, Harbin 150001, Peoples R China
5.Univ Chinese Acad Sci, Sch Phys Sci, Beijing 100049, Peoples R China
6.Univ Chinese Acad Sci, CAS Key Lab Vacuum Phys, Beijing 100049, Peoples R China
7.Univ Antwerp, EMAT, Campus Groenenborger, B-2020 Antwerp, Belgium
8.Natl Univ Singapore, Dept Phys, Singapore 117551, Singapore
9.Natl Univ Singapore, Dept Biol Sci, Singapore 117557, Singapore

Ning, Shoucong,Xu, Wenhui,Ma, Yinhang,et al. Accurate and Robust Calibration of the Uniform Affine Transformation Between Scan-Camera Coordinates for Atom-Resolved In-Focus 4D-STEM Datasets[J]. MICROSCOPY AND MICROANALYSIS,2022.

Ning, Shoucong.,Xu, Wenhui.,Ma, Yinhang.,Loh, Leyi.,Pennycook, Timothy J..,...&Loh, N. Duane.(2022).Accurate and Robust Calibration of the Uniform Affine Transformation Between Scan-Camera Coordinates for Atom-Resolved In-Focus 4D-STEM Datasets.MICROSCOPY AND MICROANALYSIS.

Ning, Shoucong,et al."Accurate and Robust Calibration of the Uniform Affine Transformation Between Scan-Camera Coordinates for Atom-Resolved In-Focus 4D-STEM Datasets".MICROSCOPY AND MICROANALYSIS (2022).