It’s been only a week ago that I wrote about the increasing competition for graphene. But as I said then, there are still some exciting advances based on graphene. An example is photonics, which is an area where traditionally graphene perhaps has not been as strong as in electronics. A reason for this is that being only a single atomic layer thin, graphene initially wasn’t expected to show much interaction with light. One of the more intriguing historic results in this area has been the fact that the absorption of light in graphene is determined by one of nature’s most fundamental numbers, the fine structure constant.
But absorption of light is not where the true potential of graphene lies, namely on the nanoscale. On the same scale as electronic applications, because ultimately the aim is to achieve photonic functionality on a chip.
However, the control of light on the nanoscale typically requires surface plasmons. These are collective movements of electrons at the surface of metals. So in a sense surface plasmons function a bit like antenna that can focus light into tiny spots. [...]