Disorder-induced gap behavior in graphene nanoribbons

摘要: We study the transport properties of graphene nanoribbons standardized 30 nm width and varying lengths. find that extent gap observed in as a function Fermi energy these ribbons (the ``transport gap'') does not have strong dependence on ribbon length, while source-drain voltage ``source-drain increases with increasing length. anneal to reduce amplitude disorder potential both shrinks moves closer zero gate voltage. In contrast, annealing systematically affect gap. conclude reflects overall strength background potential, is sensitively dependent its details. Our results support model occurs through quantum dots forming along due induced by charged impurities.