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arXiv · 1301.3795

Raman-scattering study of the phonon dispersion in twisted bi-layer graphene

J. Campos-Delgado·L. G. Cançado·C. A. Achete·A. Jorio·J. -P. Raskin
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Abstract

Bi-layer graphene with a twist angle θ between the layers generates a superlattice structure known as Moiré pattern. This superlattice provides a θ-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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J. Campos-Delgado, L. G. Cançado, C. A. Achete, A. Jorio, J. -P. Raskin. 2013-03-28. Raman-scattering study of the phonon dispersion in twisted bi-layer graphene. https://doi.org/10.1007/s12274-013-0304-z

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