title: Correlating atomic structure and transport in suspended graphene nanoribbons.
abstract: Graphene nanoribbons (GNRs) are promising candidates for next generation integrated circuit (IC) components; this fact motivates exploration of the relationship between crystallographic structure and transport of graphene patterned at IC-relevant length scales (<10 nm). We report on the controlled fabrication of pristine, freestanding GNRs with widths as small as 0.7 nm, paired with simultaneous lattice-resolution imaging and electrical transport characterization, all conducted within an aberration-corrected transmission electron microscope. Few-layer GNRs very frequently formed bonded-bilayers and were remarkably robust, sustaining currents in excess of 1.5 μA per carbon bond across a 5 atom-wide ribbon. We found that the intrinsic conductance of a sub-10 nm bonded bilayer GNR scaled with width as GBL(w) ≈ 3/4(e(2)/h)w, where w is the width in nanometers, while a monolayer GNR was roughly five times less conductive. Nanosculpted, crystalline monolayer GNRs exhibited armchair-terminated edges after current annealing, presenting a pathway for the controlled fabrication of semiconducting GNRs with known edge geometry. Finally, we report on simulations of quantum transport in GNRs that are in qualitative agreement with the observations.
authors: Department of Physics and Astronomy, University of Pennsylvania , Philadelphia, Pennsylvania 19104, United States.
authors: Zhengqing John
authors: ZJ
authors: Qi
authors: Julio A
authors: JA
authors: Rodríguez-Manzo
authors: Andrés R
authors: AR
authors: Botello-Méndez
authors: Sung Ju
authors: SJ
authors: Hong
authors: Eric A
authors: EA
authors: Stach
authors: Yung Woo
authors: YW
authors: Park
authors: Jean-Christophe
authors: JC
authors: Charlier
authors: Marija
authors: M
authors: Drndić
authors: A T Charlie
authors: AT
authors: Johnson
mesh_terms: D004553:Electric Conductivity; D006108:Graphite / Q000737:chemistry*; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure
chemical_list: D037742:Nanotubes, Carbon; D006108:Graphite