Dopant-Induced Surface Magnetism in β-SiC Controlled by Dopant Depth

First-principles calculation discloses local magnetism on the β-SiC (110) and (001) surfaces due to nonmetallic dopants. The spontaneously polarized β-SiC (111) surface without dopants also exhibits strong magnetism which can be reduced significantly by dopant incorporation. The magnetic values depend on the arrangement of superfluous p electrons and location of dopants. If the dopants reach the third and seventh layers, the dopant-induced magnetism on the (001) and (110) surfaces disappears and the nonmagnetic bulk behavior is reverted. Our results suggest that surface magnetism can be tailored by facet engineering and dopant incorporation.