  The carrier density distributions in few-layer-graphene systems grown on the
carbon face of silicon carbide can be altered by the presence of a scanning
tunneling microscope (STM) tip used to probe top-layer electronic properties,
and by a perpendicular magnetic field which induces well-defined Landau levels.
Hartree approximation calculations in the perpendicular field case show that
charge tends to rearrange between the layers so that the filling factors of
most layers are pinned at integer values. We use our analysis to provide
insight into the role of buried layers in recent few-layer-graphene STM studies
and discuss the limitations of our model.
