Graphene Unit Cell Imaging by Holographic Coherent Diffraction

TL;DR

This paper demonstrates high-resolution imaging of a graphene sheet using combined holographic coherent diffraction with low-energy electrons, enabling detailed visualization of over 660,000 unit cells in a single shot.

Contribution

It introduces a novel method combining holography and coherent diffraction for atomic-scale imaging of freestanding graphene with single-pattern reconstruction.

Findings

Achieved 2 Angstrom resolution imaging of graphene

Reconstructed entire sheet from a single diffraction pattern

Potential for imaging biological molecules on graphene

Abstract

We have imaged a freestanding graphene sheet of 210 nm in diameter with 2 Angstrom resolution by combining coherent diffraction and holography with low-energy electrons. The entire sheet is reconstructed from just a single diffraction pattern displaying the arrangement of 660.000 individual graphene unit cells at once. Given the fact that electrons with kinetic energies of the order of 100 eV do not damage biological molecules, it will now be a matter to develop methods for depositing individual proteins onto such graphene sheets.