In , we can find a concise overview of light scattering processes, especially of the Raman scattering process in graphene. We can see how the Raman peaks are generated by the presence of the optical phonons according to their dispersions in the Brillouin zone. We can also appreciate that the Raman spectrum is sensitive to the number of graphene layers, to the presence of defects and to the straining and doping of it. Therefore, we can find reiterated that the Raman technique "can give insight in the material's quality, the number of layers, and is sensitive to any changes in electric or magnetic fields, band structure and temperature, making it ideal to probe layered materials" .