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DOE OSTI · 2301802

Framework of compressive sensing and data compression for 4D-STEM

Ni, Hsu-Chih·Yuan, Renliang·Zhang, Jiong·Zuo, Jian-Min
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Abstract

Four-dimensional Scanning Transmission Electron Microscopy (4D-STEM) is a powerful technique for high-resolution and high-precision materials characterization at multiple length scales, including the characterization of beam-sensitive materials. However, the field of view of 4D-STEM is relatively small, which in absence of live processing is limited by the data size required for storage. Furthermore, the rectilinear scan approach currently employed in 4D-STEM places a resolution- and signal-dependent dose limit for the study of beam sensitive materials. Improving 4D-STEM data and dose efficiency, by keeping the data size manageable while limiting the amount of electron dose, is thus critical for broader applications. Here we introduce a general method for reconstructing 4D-STEM data with subsampling in both real and reciprocal spaces at high fidelity. The approach is first tested on the subsampled datasets created from a full 4D-STEM dataset, and then demonstrated experimentally using random scan in real-space. The same reconstruction algorithm can also be used for compression of 4D-STEM datasets, leading to a large reduction (100 times or more) in data size, while retaining the fine features of 4D-STEM imaging, for crystalline samples.

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Ni, Hsu-Chih, Yuan, Renliang, Zhang, Jiong, Zuo, Jian-Min. 2024-02-10. Framework of compressive sensing and data compression for 4D-STEM. https://doi.org/10.1016/j.ultramic.2024.113938

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