Influence of Edge Defects, Vacancies, and Potential Fluctuations on Transport Properties of Extremely Scaled Graphene Nanoribbons

Atomistic quantum transport simulations of a large ensemble of devices are employed to investigate the impact of different sources of disorder on the transport properties of extremely scaled (length of 10 nm and width of 1–4 nm) graphene nanoribbons. We report the dependence of the transport gap, on- and off-state conductances, and on–off ratio on edge-defect density, vacancy density, and potential fluctuation amplitude. For the smallest devices and realistic lattice defect densities, the transport gap increases by up to $\sim$300%, and the on–off ratio reaches almost $\sim\!\!\hbox{10}^{6}$ . We also report a rather high variation of the transport gap and on–off ratio. In contrast, we find that the potential fluctuations have a negligible impact on the transport gap and cause a relatively modest increase of the on–off ratio.