Influence of Mn and Co doping on optical and magnetic properties in 3C–SiC

Diluted magnetic semiconductors with magneto-optical properties have very attractive properties in many applications (optical magnetic modulation). However, the major challenge limiting its further development is the ability to have excellent optical properties at room temperature. Through the first principle calculation of GGA + U method based on DFT calculation, we systematically calculated the electronic structure, magnetic properties and optical properties of Mn, Co and (Mn, Co) doped 3C–SiC. By (Mn, Co) co-doped 3C–SiC, we found that the system not only can obtain high total magnetic moment, but also has ferromagnetism, and the maximum Curie temperature reaches 886 K. The reason of ferromagnetism is because these ferromagnetic states are caused by p-d hybridization between adjacent C atoms and Mn and Co atoms. In addition, we found that the vacancy defect has an effect on the ferromagnetism, which is larger when the vacancy distance dopant is 4.007 Å. At its theoretical temperature we found that the three doping systems showed a significant red shift relative to the intrinsic system. The Si31MnC32 system has the strongest absorption capacity for infrared light and ultraviolet light, while the Si30MoCoC32 system has the strongest absorption capacity for visible light. The results provide a good candidate for magnetic origin and optics.