Abstract

The transport properties of quasi-one-dimensional systems based on graphene nanoribbons are reviewed. We focus on those with metallic behavior, especially relevant for transport applications. First, we analyze the role of nanoribbons as valley filters for carbon nanotubes, as an example of those occurring in partially unzipped carbon nanotubes. Later, we describe devices made of overlapping ribbons or flakes deposited on ribbons, where quantum effects modulate their conductance. Moiré bilayer nanoribbon systems are additionally considered, for which transport is governed by the interplay of edge and stacking regions. Finally, the generation of spin-polarized currents by Rashba spin–orbit interactions in graphene nanoribbons is studied, where symmetries play an important role.