Magnetism in transition metal (Fe, Ni) co-doped 4H-SiC: a first-principles study

The electronic structure and magnetic properties of (Fe, Ni) co-doped 4H-SiC-based dilute magnetic semiconductors were investigated by first-principles calculations. The (Fe, Ni) co-doped 4H-SiC exist spin-polarization due to the introduction of dopant atoms, resulting in splitting. The co-doped system is more prone to a ferromagnetic state, and the magnetization energy is larger than some known room temperature diluted magnetic semiconductors, indicating that the room temperature ferromagnetism (FM) is higher. The results show that the (Fe, Ni) co-doped 4H-SiC system is ferromagnetic at room temperature with △E _FM −398.8 meV. The (Fe, Ni) co-doped 4H-SiC system exhibits strong magnetic properties due to strong coupling between Fe and Ni, resulting in strong spin polarization of nearby C atoms. We also studied the effect of silicon vacancies in the (Fe, Ni) co-doped 4H-SiC system. The results show that all the configurations are FM, and the FM is significantly reduced compared with the system without silicon vacancies. These results have potential applications in electronic or spintronic devices. (paper)