Atomistic Insight into the Formation of Metal-Graphene One-Dimensional Contacts

Motivated by the need to control the resistance of metal-graphene interfaces, we have simulated the structural and transport properties of edge contacts upon their formation. Our first-principles calculations reveal that the contacts evolve in a nontrivial way depending on the type of metal and the chemical contamination of the graphene edge. In particular, our results indicate that the origin of the low experimental resistance of chromium-graphene edge contacts is related to their weaker variation upon contamination and defect formation. In summary, by analyzing the distance dependence of the graphene-metal interaction and the relation between the reactivity and forces at the graphene edge, we shed new light on the mechanisms responsible for the diverse performance of experimentally fabricated graphene edge contacts.