▎ 摘　　要

We report on the fabrication and characterization of graphene three-terminal junctions with nanometer dimensions. The devices have been realized in epitaxial graphene on semi-insulating silicon carbide. All current-carrying device parts consist of graphene resulting in all-carbon structures. Pronounced voltage rectification and frequency multiplication have been observed at room temperature. (C) 2011 American Institute of Physics. [doi:10.1063/1.3653469]