Field Emission Energy Distribution from Planar Integrated Graphene

We report field emission energy distributions from planar graphene edges. Field effect transistors with integrated gate and drain electrodes and vacuum transport parallel to the substrate surface are fabricated using graphene edge emission sources are prepared from two types of graphene. The emission distributions produced by reduced graphene oxide are roughly symmetric, often contain multiple peaks, and shift over time. These characteristics suggest the emission originates in local edge states. Emission produced by high quality graphene grown on Cu foil more closely resembles emission from a linear density of states, suggesting the emission starts from the delocalized band as well as discrete states.