  Graphene edges are of particular interest, since their chirality determines
the electronic properties. Here we present a detailed Raman investigation of
graphene flakes with well defined edges oriented at different crystallographic
directions. The position, width and intensity of G and D peaks at the edges are
studied as a function of the incident light polarization. The D-band is
strongest for light polarized parallel to the edge and minimum for
perpendicular orientation. Raman mapping shows that the D peak is localized in
proximity of the edge. The D to G ratio does not always show a significant
dependence on edge orientation. Thus, even though edges can appear
macroscopically smooth and oriented at well defined angles, they are not
necessarily microscopically ordered.
