Latest Raman scattering research in various kinds of graphene samples are reviewed right here. We first talk about the first-order and the double resonance Raman scattering mechanisms in graphene, which give rise to probably the most outstanding Raman options. The dedication of the variety of layers in few-layer graphene is mentioned, giving particular emphasis to the potential for utilizing Raman spectroscopy to tell apart a monolayer from few-layer graphene stacked within the Bernal (AB) configuration. Several types of graphene samples produced each by exfoliation and utilizing epitaxial strategies are described and their Raman spectra are in contrast with these of 3D crystalline graphite and turbostratic graphite, during which the layers are stacked with rotational dysfunction. We present that Resonance Raman research, the place the vitality of the excitation laser line may be tuned repeatedly, can be utilized to probe electrons and phonons close to the Dirac level of graphene and, particularly permitting a dedication to be made from the tight-binding parameters for bilayer graphene. The particular technique of electron–phonon interplay that renormalizes the phonon vitality giving rise to the Kohn anomaly is mentioned, and is illustrated by gated experiments the place the place of the Fermi stage may be modified experimentally. Lastly, we talk about the power of distinguishing armchair and zig-zag edges by Raman spectroscopy and research in graphene nanoribbons during which the Raman sign is enhanced on account of resonance with singularities within the density of digital states.
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