Evidencing the existence of intrinsic half-metallicity and ferromagnetism in zigzag gallium sulfide nanoribbons.

The achievement of half-metallicity with ferromagnetic (FM) coupling has become a key technology for the development of one-dimensional (1D) nanoribbons for spintronic applications. Unfortunately, in previous studies, such a half-metallicity always occurs upon certain external constraints. Here we, for the first time, demonstrate, via density functional theory (DFT), that the recent experimentally realized gallium sulfide nanoribbons (GaSNRs) can display an intrinsic half-metallic character with FM coupling, raised from Ga-4s, Ga-4p and S-3p states at the Ga-dominated edge. Furthermore, the novel half-metallic behavior with FM coupling here is rather robust, especially for GaSNRs with large width and thickness, and can be sustained to the room temperature. Thus, our results accidentally disclose a new 1D spin nanomaterial, which allows us to go beyond the current scope limited to the graphene, boron nitride (BN), zinc oxide (ZnO) and molybdenum sulfide (MoS2) nanoribbons, toward more realistic spintronic applications.