Moving silicon atoms in graphene with atomic precision

In recent years, it has become possible to see directly individual atoms using electron microscopy - especially in graphene, the one-atom-thick sheet of carbon. An international collaboration between the University of Vienna and research teams from the UK and the US has shown how an electron beam can move silicon atoms through the graphene lattice without causing damage. The research combines advanced electron microscopy with demanding computer simulations and is published in the premier physics journal Physical Review Letters. Richard Feynman famously posed the question in 1959: is it possible to see and manipulate individual atoms in materials? For a time his vision seemed more science fiction than science, but starting with groundbreaking experiments in the late 1980s and more recent developments in electron microscopy instrumentation it has become scientific reality. However, damage caused by the electron beam is often an issue in such experiments. The present study focused on single-layer graphene with silicon atoms embedded into the lattice, previously created and studied by the collaborators from Manchester and Daresbury in the UK. Due to the larger size of silicon compared to carbon, these dopant atoms protrude out from the plane, which makes for interesting dynamics under the electron beam.