TUD

Reduced symmetry conditions on high-index vicinal copper surfaces are exploited to efficiently imprint well-defined structural and electronic modulations in continuous graphene sheets. The combination of conventional microscopy with wave vector resolved photoemission electron microscopy (k-PEEM) allows to locally distinguish different levels of interaction of graphene with three coexisting copper facets (111), (110), and (221), which lead to alternating doping levels at the nanoscale. Ordering is driven by surface energy minimization, inducing anisotropic copper and carbon mass-transfers during high temperature chemical vapor deposition.