Manipulation at a distance: Atomic-scale observation of ballistic electron transport in single layer graphene

Abstract

We present scanning tunneling microscopy manipulation experiments on epitaxial graphene and the carbon buffer layer grown on hexagonal silicon carbide. Low voltage pulses applied to the graphene layer with the microscope tip induce nonlocal modifications of a bare carbon buffer region 10 nm away. The graphene itself is not affected. This is direct evidence for ballistic hot electrons propagating along the graphene layer to the graphene edge. High energy states in the graphene band structure (Van Hove Singularities) may explain both the electron transport and the coupling of the graphene edge to the adjacent bare carbon buffer region. (C) 2013 AIP Publishing LLC.