It's been long known that adding calcium atoms between graphene sheets can make it superconductive. Now researchers from the US DoE SLAC National Accelerator Laboratory and Stanford University showed for the first time graphene's role in the superconductivity of this materials (called CaC6).
The researchers used intense ultraviolet light beams to see the structure of the CaC6 material. Using the light one can see how electrons scatter back and forth between the graphene and the calcium, interact with natural vibration in the atomic structure of the CaC6, and pair up to conduct electricity without resistance.
It is know understood that both the graphene and the calcium atoms are crucial to make CaC6 superconductive.