Disorder density of states in supported graphene

Abstract

Transport in graphene is impacted by disorder. Disorder, which can occur on supported graphene, manifests as a significant shift in the Fermi level position from the charge neutrality point (Dirac point) and leads to carrier scattering. Here, we provide a direct measurement of the disorder density of states (DOS). We show that the disorder is extrinsic to graphene and is characterized by a continuum of DOS located at the graphene-substrate interface. A key feature is a Gaussian-like DOS that causes pinning of the Fermi level and the shift in the Dirac point.