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arXiv · 1207.2399

Low-energy electron transmission imaging of clusters on free-standing graphene

Jean-Nicolas Longchamp·Tatiana Latychevskaia·Conrad Escher·Hans-Werner Fink
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Abstract

We investigated the utility of free-standing graphene as a transparent sample carrier for imaging nanometer-sized objects by means of low-energy electron holography. The sample preparation for obtaining contamination-free graphene as well as the experimental setup and findings are discussed. For incoming electrons with 66 eV kinetic energy graphene exhibits 27% opacity per layer. Hence, electron holograms of nanometer-sized objects adsorbed on free-standing graphene can be recorded and numerically reconstructed to reveal the object's shapes and distribution. Furthermore, a Moire effect has been observed with free-standing graphene multi-layers.

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Jean-Nicolas Longchamp, Tatiana Latychevskaia, Conrad Escher, Hans-Werner Fink. 2012-07-10. Low-energy electron transmission imaging of clusters on free-standing graphene. https://doi.org/10.1063/1.4752717

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