Giant low bias negative differential resistance induced by nitrogen doping in graphene nanoribbon

By applying nonequilibrium Green's function formalism in combination with density functional theory, we have investigated the electronic transport properties of armchair graphene nanoribbon devices with periodic nitrogen-doping. Giant negative differential resistance behaviors with peak-to-valley ratio up to the order of 10(5) can be obtained in the mV bias regime by tuning the position and the concentration of the dopants. The negative differential resistance behavior is understood in terms of the evolution of the transmission spectrum and band structures with applied bias combined with the symmetry analyses of the Bloch wave functions of the corresponding subbands. (C) 2012 Elsevier B.V. All rights reserved.