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تسجيل مستخدم جديدElectronic Raman Scattering in Twistronic Few-Layer Graphene
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We study electronic contribution to the Raman scattering signals of two-, three- and four-layer graphene with layers at one of the interfaces twisted by a small angle with respect to each other. We find that the Raman spectra of these systems feature two peaks produced by van Hove singularities in moir{e} minibands of twistronic graphene, one related to direct hybridization of Dirac states, and the other resulting from band folding caused by moir{e} superlattice. The positions of both peaks strongly depend on the twist angle, so that their detection can be used for non-invasive characterization of the twist, even in hBN-encapsulated structures.
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Bi-layer graphene with a twist angle theta between the layers generates a superlattice structure known as Moir{e} pattern. This superlattice provides a theta-dependent q wavevector that activates phonons in the interior of the Brillouin zone. Here we
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