First-Principles Study of the Effect of Native Defects on Spin Polarization and Exchange Coupling Interaction in Semimetal VO.

We use first-principles calculations to investigate the mechanism of the effect of native defects on the spin polarization and exchange coupling interaction in the VO semimetal material. Our results reveal that, in contrast to other neutral defects, V vacancy defects in VO at A/B sites are in favor of higher spin polarization degrees and lower defect formation energies. Compared to ideal VO, the V vacancy defects at A/B sites cause slightly lower spin polarization degrees but much higher exchange coupling interactions. Our results suggest an effective route to mediate the spin polarization and exchange coupling by defect engineering, which promotes the applications of the VO semimetal material in spintronics.