Bilayer graphene with a twist angle O between the layers generates a superlattice structure known as a Moir6 pattern. This superlattice provides a O-dependent q wavevector that activates phonons in the interior of the...Bilayer graphene with a twist angle O between the layers generates a superlattice structure known as a Moir6 pattern. This superlattice provides a O-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 bilayer graphene （tBLG）. The effect reported here is different from the widely 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.展开更多
文摘Bilayer graphene with a twist angle O between the layers generates a superlattice structure known as a Moir6 pattern. This superlattice provides a O-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 bilayer graphene （tBLG）. The effect reported here is different from the widely 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.
