3C-SiC电子结构和磁性的第一性原理计算

First-principles Calculation of Electronic Structures and Magnetic Properties in 3C-SiC

采用基于密度泛函理论的第一性原理平面波赝势方法,分别计算了Si空位、单个Al、Al与Si空位共掺杂3C-Si C的电子结构和磁性。结果表明:本征3C-Si C没有磁性,单一的Al掺杂对其磁性的改进也没有影响,但可以通过Si空位的引入产生自旋极化。在A1和Si空位共掺杂3C-Si C的结构中,Si空位近邻的C原子的自旋向上与自旋向下的态密度图明显不对称,主要是由与Si空位近邻的C-2p轨道的自旋极化引起的。

The electronic structures and magnetic properties of 3C-SiC with different doping amounts of A1 and Si vacancies were investigated via the first-principle plane wave pseudo-potential method based on the density functional theory. The calculated results show that the intrinsic 3C-SiC is nonmagnetic, single A1 dopant has no effect on the improvement of magnetic properties, and the Si vacancy dopant can induce the spin-polarization. In A1 and Si vacancies co-doped 3C-SiC, C atoms neighbor Si vacancy spin up and down the spin state density diagram of asymmetry, which is located on the C-2p orbital adjacent Si vacancy.