Raman 2D-Band Splitting in Graphene: Theory and Experiment

We present a systematic experimental and theoretical study of the two phonon (2D) Raman scattering in graphene undar uniaxial tension, The external perturbation unveils that the 2D mode excited with 785 nm has a complex,line-shape mainly due to the contribution of two distinct double resonance scattering processes (inner and outer) in the Raman signal. The splitting depends on the direction of the applied strain and the polarization of the incident light The results give new insight into the nature of the 2D band and have. significant implications for the use of graphene as reinforcement In composites since the 2D mode is crucial to assess how effectively graphene uptakes an applied stress or strain