First-principles calculations are performed to investigate the electronic structures and magnetic properties of (Fe, Co)-codoped 4H-SiC using the generalized gradient approximation plus Hubbard U method. We find that 4H-SiC doped with an isolated Fe atom and an isolated Co atom produces a total magnetic moment of 5.98 μ B and 6.00 μ B respectively. We estimate T C of about 263.1 K for the (Fe, Co)-codoped 4H-SiC system. We study ferromagnetic and antiferromagnetic coupling in (Fe, Co)-codoped 4H-SiC. Ferromagnetic behavior is observed. The strong ferromagnetic couplings between local magnetic moments can be attributed to p–d hybridization between Fe, Co and neighboring C. However, the (Fe, Co, V Si )-codoped 4H-SiC system shows antiferromagnetic coupling when an Si vacancy is introduced in the same 4H-SiC supercell. The results may be helpful for further study on transition metal-codoped systems.

中文翻译：

---

基于密度泛函理论的（Fe，Co）掺杂4H-SiC中铁磁性的机理

使用广义梯度近似加Hubbard U方法进行第一性原理计算以研究（Fe，Co）掺杂的4H-SiC的电子结构和磁性能。我们发现，掺杂有孤立的Fe原子和孤立的Co原子的4H-SiC产生的总磁矩分别为5.98μB和6.00μB。对于（Fe，Co）掺杂的4H-SiC系统，我们估计TC约为263.1 K. 我们研究（Fe，Co）掺杂的4H-SiC中的铁磁和反铁磁耦合。观察到铁磁行为。局部磁矩之间的强铁磁耦合可以归因于Fe，Co与相邻C之间的p–d杂化。但是，当引入Si空位时，（Fe，Co，V Si）掺杂的4H-SiC系统表现出反铁磁耦合。在同一4H-SiC超级电池中。