Effects of Localized Disorder on the Quantum Transport Property of a Four-Terminal Graphene Nanodevice

In this paper, a numerical study of quantum transport in a disordered four-terminal graphene nanodevice (FTGN) are investigated based on the Landauer approach. The effects of localized disorder on transmission coefficient of the electron injected into the system and on the transport length scale is studied using tight-binding model. The transmission coefficient of a four-terminal graphene nanodevice (FTGN) with a single localized disorder depends on both the location of the disorder and the energy of the electron near E = 0, a single localized disorder causes the transmission coefficient of the system to be decreased in comparision with the pure system. The mean free path (l(e)) in the system is reduced when the strength of localized disorder is sufficiently high. When two-localized disorder is introduced into the system, the transmission coefficient and the transport length scale of the system depends not only on the distance between the two-disorders, but on the strength of the disorder and the symmetry of the two sub-lattices in honeycomb structure.