The surprising insulating and superconducting states of narrow-band graphene twisted bilayers have been mostly discussed so far in terms of strong electron correlation, with little or no attention to phonons and electron-phonon effects. We found that, among the 33492 phonons of a fully relaxed 1.08° twisted bilayer, there are few special, hard, and nearly dispersionless modes that resemble global vibrations of the moiré supercell ('moirè phonons').
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