Spin filtering in oxidized zigzag graphene nanoribbons

Abstract

It is well-known that confinement effects in graphene nanoribbons have a significant effect on the electronic and transport properties of graphene. These properties of pristine graphene nanoribbons have been studied theoretically as well as experimentally. Here, we report the transport properties of oxidized zigzag graphene nanoribbons by using density functional theory (DFT) based non-equilibrium Green's function (NEGF) approach. The results show that the oxygen adatoms lift the spin degeneracy in the conductance. This fact leads to significant changes in transport properties. Further, the present results show that when the ribbon basal plane is oxidized, the conductance is strongly suppressed in both conduction and valence band region away from the fermi level. It is shown to occur due to the charge transfer between the ribbon's basal plane and the oxygen atom(s). These results suggest that these nanoribbons may be used for spin-filtering applications.