Detection of edge defects using circularly polarized light in the Raman spectroscopy of 2H-MoS 2

Abstract The intensity of the Raman signal depends on the selection rules, relative crystallographic orientation of the sample and polarization of the incident/ scattered light. Here we have analyzed polarization-dependent Raman spectroscopy on the edge and the basal plane of layered MoS 2 under linear and circular polarizations. We have also theoretically calculated the intensity of various Raman modes in basal plane and edge of MoS 2 and obtained an excellent agreement with the theory and the experiment. It has been concluded that the Raman vibration modes at the edge show a strong polarization dependency due to the anisotropic nature of MoS 2 . Circularly polarized light can be employed to detect the edge defects in MoS 2 thereby enabling a deeper understanding of the anisotropic characteristics and the symmetry breaking at the defect sites.