Half-metallicity in hybrid BCN nanoribbons

The established chemical synthetic strategy toward graphene nanoribbons has greatly prompted and justified the research of theoretical designs of novel materials based on graphene. In this paper, we report the novel half-metallicity in C and BN hybrid zigzag nanoribbons even though stand-alone C or BN nanoribbon possesses a finite band gap. By performing first-principles electronic-structure calculations, we find this unexpected half-metallicity in the hybrid nanostructures stems from a competition between the charge and spin polarizations, as well as from the pi orbital hybridization between C and BN. Molecular dynamics simulations indicate that the hybrid nanoribbons are stable. Our results point out a possibility of making spintronic devices solely based on nanoribbons and a new way of fabricating metal-free half metals.