Neutral vacancy-defect-induced magnetism in SiC monolayer

We perform first-principles calculations to investigate the spin-polarization of vacancy defects in SiC monolayer. We show that Si and C vacancy defects play different roles in the magnetism of SiC monolayer. Local magnetic moments can be induced by the presence of Si vacancy (VSi) whereas no spin-polarization occurs in C vacancy (VC) defects. The induced states are due to the unpaired electrons on carbon atoms surrounding the silicon vacancy. Interestingly, starting from different initial spin distributions, two spin configurations with S=1 and 2 are obtained, and the energy difference between them is only 39 meV. The spatial distribution of spin density displays the features of ferrimagnetic alignments for the most stable configuration.