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arXiv · 1910.04227

An algorithm for Bragg coherent X-ray diffractive imaging of highly strained nanocrystals

Ziyi Wang·Oleg Gorobtsov·Andrej Singer
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Abstract

By using phase retrieval, Bragg Coherent Diffractive Imaging (BCDI) allows tracking of three-dimensional displacement fields inside individual nanocrystals. Nevertheless, in the presence of significant (1% and higher) strains, such as in the process of a structural phase transformation, fails due to the Bragg peak distortions. Here we present an advanced BCDI algorithm enabling imaging three-dimensional strain fields in highly strained crystals. We test the algorithm on particles simulated to undergo a structural phase transformation. While the conventional algorithm fails in unambiguously reconstructing the phase morphology, our algorithm correctly retrieves the morphology of coexistent phases with a strain difference of 1%. The key novelty is the simultaneous reconstruction of multiple scans of the same nanoparticle at snapshots through the phase transformations. The algorithm enables visualizing phase transformations in nanoparticles of lithium-ion, sodium-ion nanoparticles, and other nanoparticulate materials in working conditions (operando).

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Ziyi Wang, Oleg Gorobtsov, Andrej Singer. 2019-10-09. An algorithm for Bragg coherent X-ray diffractive imaging of highly strained nanocrystals. https://doi.org/10.1088/1367-2630%2Fab61db

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