Electron transmission probability Across a disordered nanoribbon graphene

Graphene sheet which can be classified as the most important materials precisely in the last three years is made out of the carbon atoms placed in a honeycomb configuration as the geometry of graphitic structures. Graphite is formed by the graphene layers stacking on top of the other composed by the weak Van der Waals forces.Its noticeable characteristics in nanoscale sizes, such as having a good conductivity, flexibility, and being masless, chiral , Dirac fermions in its low energy excitations, sets it clearly in the focus of attention among the materials. Although graphene is the base form of all carbon allotropes, it still had not been expected to exist in the free state before the last four years [1].Using the single band tight-binding model, we studied the band structure of the clean zigzag and armchair graphene ribbons and impure cases. So important is the existence of the bands crossing the Fermi energy in the presence of the impurities that can be led to an increased conductivity.