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arXiv · 1310.1755

Structural manipulation of the graphene/metal-interface with Ar+ irradiation

E. H. Åhlgren·S. K. Hämäläinen·O. Lehtinen·P. Liljeroth·J. Kotakoski
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Abstract

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.

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E. H. Åhlgren, S. K. Hämäläinen, O. Lehtinen, P. Liljeroth, J. Kotakoski. 2013-10-07. Structural manipulation of the graphene/metal-interface with Ar+ irradiation. https://doi.org/10.1103/physrevb.88.155419

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