Half metallicity in bare BC2N nanoribbons with zigzag edges

We study the electronic and magnetic properties of bare zigzag BC2N nanoribbons (ZBC2NNRs) by using first principles calculations. The ZBC2NNRs which we studied are assigned to four edge types, and we carefully examine the size effect and edge magnetic coupling orders. We find that the N edge and the C edge adjacent to N atoms have a ferromagnetic coupling, while the B edge and the C edge adjacent to B atoms have an anti-ferromagnetic coupling. These novel properties arise from the unsaturated edge with specific edge determined magnetic moment distribution. All the investigated ribbons exhibit magnetic ground states with room-temperature accessible half-metallic character, irrespective of the ribbon width. Our results suggest that ZBC2NNRs can have potential applications in spintronics.