Imaging defects in two-dimensional crystals by convergent beam electron diffraction

Tatiana Latychevskaia; Pengru Huang; Kostya S. Novoselov

doi:10.1103/physrevb.105.184113

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arXiv · 2610.21542

Imaging defects in two-dimensional crystals by convergent beam electron diffraction

Tatiana Latychevskaia·Pengru Huang·Kostya S. Novoselov

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Abstract

Convergent beam electron diffraction (CBED), recently demonstrated on two-dimensional (2D) materials, offers a number of interesting applications such as imaging atomic in- and out-of plane shifts, interlayer distances, and individual adsorbates. In this study, we show how CBED allows for atomic-precision imaging of individual defects in 2D materials using one single-shot intensity measurement. In combination with structural calculations using density functional theory, we present simulated CBED patterns for various defects in graphene, each of which exhibits a unique fingerprint distribution. We also show how atomic positions, including the individual atomic defects in graphene, can be reconstructed by iterative phase retrieval from a single CBED pattern.

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Tatiana Latychevskaia, Pengru Huang, Kostya S. Novoselov. 2026-10-15. Imaging defects in two-dimensional crystals by convergent beam electron diffraction. https://doi.org/10.1103/physrevb.105.184113

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