Researchers from Aalto University in Finland and Utrecht University in the Netherlands managed to create single-atom contacts to connect gold and graphene nanoribbons. In their experiments, they showed how a single chemical bond can be used to make an electrical contact to a graphene nanoribbon.
Using atomic force microscopy (AFM) and scanning tunneling microscopy (STM), the researchers mapped the structure of the graphene nanoribbons and then used voltage pulses from the tip of the scanning tunnelling microscope to form single bonds to the graphene nanoribbons, at a precise, specific location. The electric pulse removed a single hydrogen atom from the end of a graphene nanoribbon and this initiates the bond formation.
Studying the results, the researchers discovered that this single chemical bond forms an electronically transparent contact with the graphene nanoribbon – without affecting its overall electronic structure.