We reexamine the electronic structure of graphene on SiC substrate by angle-resolved photoemission spectroscopy. We directly observed multiply cloning of Dirac cone, in addition to ones previously attributed to reconstruction. The locations, relative distances and anisotropy of Dirac cone replicas fully agree with the moire pattern of graphene-SiC heterostructure. Our results provide a straightforward example of moire potential modulation in engineering electronic structure with Dirac fermions.
تحميل البحث