The neaSCOPE microscopes can be used, among other things, to visualize Dirac plasmon on a graphene monolayer, and with their help it is also possible to monitor electrical tuning. The experiment involved the release of plasmon from the tip, their propagation and subsequent reflection from the edge of the graphene layer, and the effect of backscatter amplitude. Two unique features of the neaSNOM microscope have contributed to the success of this measurement:
- High spatial resolution <20 nm made it easy to distinguish plasmon standing waves with small periods (approx. 100 nm)
- and more precisely defined radiation at the tip, which helps to effectively trigger plasmons and gives them the necessary "kick" momentum (50 times larger than photons)
Graphene is a fascinating material with remarkable strength and high electron conductivity. It is also receiving attention because it could become the basis of next-generation computer components. At the moment when the electrical tuning of plasmon was demonstrated, graphene transistors can be considered: they could be excited electrically or optically, in nanometer dimensions.
You can find out about this and other applications here.