Low-energy electron transmission imaging of clusters on free-standing graphene
Citation
Authors: Jean-Nicolas Longchamp, Tatiana Latychevskaia, Conrad Escher, and Hans-Werner Fink
Title: Low-energy electron transmission imaging of clusters on free-standing graphene
Journal: Applied Physics Letters
Volume: 101
Issue: 11
Article Number: 113117
Year: 2012
DOI: https://doi.org/10.1063/1.4752717
Keywords
- Graphene
- Low-energy electron holography
- Transmission electron microscopy (TEM)
- Moiré pattern
- Sample carrier/substrate
- Nanometer-sized objects
- Transparency
- Numerical reconstruction
Brief
Free-standing graphene acts as a transparent sample carrier for imaging nanometer-sized objects using low-energy electron holography because it is transparent to low-energy electrons and ensures uniform field distribution, which eliminates artifacts and simplifies the reconstruction of recorded holograms.
Summary
This article, published in 2012 in the journal Applied Physics Letters, explores the use of free-standing graphene as a sample carrier for imaging nanoscale objects with low-energy electron holography. The authors, Jean-Nicolas Longchamp, Tatiana Latychevskaia, Conrad Escher, and Hans-Werner Fink, explain that low-energy electrons are well-suited for imaging biological specimens because they cause minimal radiation damage.
Here are the key findings from the article:
- The authors found that free-standing graphene exhibits 27% opacity per layer for electrons with 66 eV kinetic energy. This level of transparency makes it possible to record electron holograms of objects deposited on the graphene.
- The authors observed a Moiré effect in free-standing graphene multi-layers, confirming previous observations made with other microscopy techniques.
- They conclude that graphene is a suitable sample carrier for low-energy electron holography because it is reasonably transparent to electrons, ensures a well-defined field distribution, and produces holograms that can be easily reconstructed. The authors suggest that these properties make graphene promising for imaging biomolecules.
Origin: https://pubs.aip.org/aip/apl/article/101/11/113117/127463