The experimental isolation of graphene, one monolayer of graphite, has generated great interest partly because of the potential of carbon-based nano-scale electronics but also for fundamental reasons. Experiments have shown that the charge conductivity of graphene reaches a minimal value of order e2/h. It has also been found that the conductivity is linearly dependent on the electron density. Furthermore, an unconventional half-integer quantum Hall effect has been discovered. These experiments are in qualitative agreement with theoretical results based on the effective low-energy Dirac theory of graphene.
Measurements of other quantities than the charge conductance can provide additional and valuable information of graphene properties. In a recent study we have predicted that the thermopower can provide information about impurities in graphene[1], which has been qualitatively confirmed experimentally very recently. Current efforts include extensions to nanostructured graphene, such as nanoribbons[2]. [1] T. Löfwander and M. Fogelström, Phys.
[1] T. Löfwander and M. Fogelström, Phys. Rev. B 76, 193401 (2007)
[2] V. Ebrahimi, M.Sc. thesis, Chalmers 2008