Ballistic transport of graphene pnp junctions with embedded local gates.

  title={Ballistic transport of graphene pnp junctions with embedded local gates.},
  author={Seunggeol Nam and Dong-Keun Ki and Jong Wan Park and Youngwook Kim and Jun Sung Kim and Hu-Jong Lee},
  volume={22 41},
We fabricated graphene pnp devices, by embedding pre-defined local gates in an oxidized surface layer of a silicon substrate. With neither deposition of dielectric material on the graphene nor electron-beam irradiation, we obtained high-quality graphene pnp devices without degradation of the carrier mobility even in the local-gate region. The corresponding increased mean free path leads to the observation of ballistic and phase-coherent transport across a local gate 130 nm wide, which is about… Expand
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