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arXiv · 1610.06420

Imaging the potential distribution of individual charged impurities on graphene by low-energy electron holography

Tatiana Latychevskaia·Flavio Wicki·Conrad Escher·Hans-Werner Fink
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Abstract

While imaging individual atoms can routinely be achieved in high resolution transmission electron microscopy, visualizing the potential distribution of individually charged adsorbates leading to a phase shift of the probing electron wave is still a challenging task. Low-energy electrons (30 - 250 eV) are sensitive to localized potential gradients. We employed low-energy electron holography to acquire in-line holograms of individual charged impurities on free-standing graphene. By applying an iterative phase retrieval reconstruction routine we recover the potential distribution of the localized charged impurities present on free-standing graphene.

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Tatiana Latychevskaia, Flavio Wicki, Conrad Escher, Hans-Werner Fink. 2017-08-02. Imaging the potential distribution of individual charged impurities on graphene by low-energy electron holography. https://doi.org/10.1016/j.ultramic.2017.07.019

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