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arXiv · 2204.08157

Deep Learning Coherent Diffractive Imaging

Abstract

We report the development of deep learning coherent electron diffractive imaging at sub-angstrom resolution using convolutional neural networks (CNNs) trained with only simulated data. We experimentally demonstrate this method by applying the trained CNNs to directly recover the phase images from electron diffraction patterns of twisted hexagonal boron nitride, monolayer graphene and a Au nanoparticle with comparable quality to those reconstructed by a conventional ptychographic method. Fourier ring correlation between the CNN and ptychographic images indicates the achievement of a spatial resolution in the range of 0.70 and 0.55 angstrom (depending on different resolution criteria). The ability to replace iterative algorithms with CNNs and perform real-time imaging from coherent diffraction patterns is expected to find broad applications in the physical and biological sciences.

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Dillan J. Chang, Colum M. O'Leary, Cong Su, Salman Kahn, Alex Zettl, Jim Ciston, Peter Ercius, Jianwei Miao. 2022-04-18. Deep Learning Coherent Diffractive Imaging. https://arxiv.org/abs/2204.08157

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