Effects of Stone-Wales defect on the electronic and transport properties of bilayer armchair graphene nanoribbons

We report a first principles study on the electronic and transport properties of bilayer armchair graphene nanoribbons (BLAGNRs) containing Stone-Wales (SW) defect. It is shown that in the presence of SW defect in BLAGNRs, some electron localization occurs in defect atoms and degradation of transmission is observed in specific energy regions. The strength of electron localization is dependent on the symmetry of SW defect. In case of symmetric SW defect, stronger electron localization leads to sharper dip in its transmission spectrum in comparison with the broad dip in the transmission spectrum of the BLAGNR containing asymmetric SW defect. The effect of electron localization is also evident from the calculated I-V characteristics of pristine and defected structures which shows the reduced current in defected structures with respect to pristine structure. Most current reduction is observed in symmetric SW defected BLAGNR due to the stronger electron localization in symmetric SW defect.