Doping induced spin filtering effect in zigzag graphene nanoribbons with asymmetric edge hydrogenation

The magnetic and spin dependent transport properties of asymmetrically hydrogenated zigzag graphene nanoribbons, which are C-H2 bonded at one edge while C-H bonded at the other, are investigated from first-principles calculations. Due to their special distributions of the density of states near Fermi level, a perfect (100%) spin filtering effect can be achieved in such graphene nanoribbons through p-type or n-type doping. Moreover, a negative differential resistance effect is observed in both doping case, which results from the reducing of conductance near Fermi level with increasing bias voltage. (C) 2011 American Institute of Physics. [doi:10.1063/1.3559001]