Controlled defect creation is a prerequisite for the detailed study of disorder effects in materials. Here, we irradiate a graphene/Ir(111)-interface with low-energy Ar+ to study the induced structural changes. Combining computer simulations and scanning-probe microscopy, we show that the resulting disorder manifests mainly in the forms of intercalated metal adatoms and vacancy-type defects in graphene. One prominent feature at higher irradiation energies (from 1 keV up) is the formation of line-like depressions, which consist of sequential graphene defects created by the ion channeling within the interface -- much like a stone skipping on water. Lower energies result in simpler defects, down to 100 eV where more than one defect in every three is a graphene single vacancy.
@article{arxiv.1310.1755,
title = {Structural manipulation of the graphene/metal-interface with Ar+ irradiation},
author = {E. H. Åhlgren and S. K. Hämäläinen and O. Lehtinen and P. Liljeroth and J. Kotakoski},
journal= {arXiv preprint arXiv:1310.1755},
year = {2013}
}