  The magnetoconductance of graphene nanoribbons with rough zigzag and armchair
edges is studied by numerical simulations. nanoribbons with sufficiently small
bulk disorder show a pronounced magnetoconductance minimum at cyclotron radii
close to the ribbon width, in close analogy to the wire peak observed in
conventional semiconductor quantum wires. In zigzag nanoribbons, this feature
becomes visible only above a threshold amplitude of the edge roughness, as a
consequence of the reduced current density close to the edges.
