title: Lower Electric Field-Driven Magnetic Phase Transition and Perfect Spin Filtering in Graphene Nanoribbons by Edge Functionalization.
abstract: Perfect spin filtering is an important issue in spintronics. Although such spin filtering showing giant magnetoresistance was suggested using graphene nanoribbons (GNRs) on both ends of which strong magnetic fields were applied, electric field controlled spin filtering is more interesting due to much easier precise control with much less energy consumption. Here we study the magnetic/nonmagnetic behaviors of zigzag GNRs (zGNRs) under a transverse electric field and by edge functionalization. Employing density functional theory (DFT), we show that the threshold electric field to attain either a half-metallic or nonmagnetic feature is drastically reduced by introducing proper functional groups to the edges of the zGNR. From the current-voltage characteristics of the edge-modified zGNR under an in-plane transverse electric field, we find a remarkable perfect spin filtering feature, which can be utilized for a molecular spintronic device. Alteration of magnetic properties by tuning the transverse electric field would be a promising way to construct magnetic/nonmagnetic switches.
authors.affiliation: Center for Superfunctional Materials and ‡Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , 50 UNIST-gil, Ulsan 44919, Korea.
authors.forename: M Reza
authors.initials: MR
authors.lastname: Rezapour
authors.affiliation: Center for Superfunctional Materials and ‡Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , 50 UNIST-gil, Ulsan 44919, Korea.
authors.forename: Jeonghun
authors.initials: J
authors.lastname: Yun
authors.affiliation: Center for Superfunctional Materials and ‡Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , 50 UNIST-gil, Ulsan 44919, Korea.
authors.forename: Geunsik
authors.initials: G
authors.lastname: Lee
authors.affiliation: Center for Superfunctional Materials and ‡Department of Chemistry, Ulsan National Institute of Science and Technology (UNIST) , 50 UNIST-gil, Ulsan 44919, Korea.
authors.forename: Kwang S
authors.identifier: http://orcid.org/0000-0002-6929-5359
authors.initials: KS
authors.lastname: Kim