Stimulated Raman Scattering in Two-Dimensional Materials*

In this work we will show some of our progress for imaging two dimensional materials Stimulated Raman Scattering (SRS) and with coherent anti-stokes spectrocopy (CARS). The number of different two dimensional materials increases every day, with different interesting physical properties and possible applications. Therefore a fast and non-destructive imaging and spectroscopies technics to find and characterize these materials is highly desirable. We have studied the Coherent Anti-Stokes Raman Spectrum in graphene and h-BN. For the case of h-BN was observed an increase in the intensity of anti-Stokes signal when the energy difference between the pump laser and Stokes is equal to the phonon energy of the h-BN (1365 cm^-1) . However, in samples of graphene the signal was decreased when the energy difference between the lasers is equal with the phonon energy in graphene (1590 cm^-1). We will address the causes for the observation of this phenomenon based on different electronic structures of these two materials, leading to a Fano lineshape in the spectrum. Finally, we will also discuss the application of SRS imaging in fewlayers of h-BN in order to identify these layers by a fast imaging technique.