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تسجيل مستخدم جديدRaman-scattering study of the phonon dispersion in twisted bi-layer graphene
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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 show that this superlattice-induced Raman scattering can be used to probe the phonon dispersion in twisted bi-layer graphene (tBLG). The effect reported here is different from the broadly studied double-resonance in graphene-related materials in many aspects, and despite the absence of stacking order in tBLG, layer breathing vibrations (namely ZO phonons) are observed.
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