Epigraphene: the first viable platform for seamless zero-mode graphene nanoelectronics

Abstract A graphene nanoelectronics platform -envisioned as scalable seamlessly integrated graphene nanoscale devices -has failed to materialize due to pervasive edge disorder caused by lithographic processes that diminish the mobility and destroy the edge state in exfoliated graphene nanoribbons. Here we demonstrate, for the first time, graphene edge state transport in conventionally patterned graphene ribbon networks produced on graphene that is epitaxially grown on non-polar faces of electronics grade silicon carbide wafers (epigraphene). The epigraphene edge state is extremely robust to lithography processing, as the graphene edge atoms bind to the SiC substrate. The protected edge state has a mean free path that is greater than 50 microns, 5000 times greater than the bulk states. It involves a non-degenerate, spin polarized, zero-energy electronic band that does not produce a Hall voltage. In seamless integrated structures, the edge state forms a zero-energy one-dimensional ballistic network with essentially dissipationless nodes at ribbon-ribbon junctions. Its novel properties point to an unconventional charge carrier that is half-electron and half-hole. Seamless integrated graphene edge state device structures that are phase coherent at low temperatures offer a variety of switching possibilities. This makes epigraphene the only technologically viable graphene nanoelectronics platform that has the potential to succeed silicon nanoelectronics.