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基于第一性原理密度泛函理论(DFT)的广义梯度近似(GGA)的平面波赝势法(PBE),计算了 4H-SiC的本征体系、过渡金属元素Mo单掺杂4H-SiC体系的电子结构、磁性和光学特性.结果表明:Mo捧杂将导致4H-SiC由本征非磁性变为p型磁性半导体材料,其带隙值由2.88 eV变为0.55 eV.当Mo掺杂浓度为1.359 ×1021 cm-3时,磁矩为0.98 μB,这表明掺Mo后的4H-SiC材料可以作为自旋电子元器件的备选材料.此外,Mo掺杂4H-SiC体系在(100)和(001)方向的静态介电常数分别为3.780和3.969.介质函数虚部不为0的起始点发生红移,表明掺杂使电子更容易跃迁.“,”The electronic structures,magnetic and optical properties of the intrinsic and Mo-doped 4H-SiC have been systematically investigated by using density functional theory,which is based on first principles generalized gradient approximation(GGA)plane wave and plane wave pseudo-potential method(PBE).The results show that undoped 4H-SiC is an indirect band gap nonmagnetic semiconductor with the band gap value of 2.88 eV.However,Mo-doped 4H-SiC is a p-type magnetic semiconductor material with the band gap value of 0.55 eV.When the Mo concentration is 1.359 × 1021cm-3,the magnetic moment is 0.98 μB.The calculation results indi?cated that the Mo-doped 4H-SiC can be used as alternative material for Spintronic Devices.The static permittivity of Mo-doped 4H-SiC system in(100)and(001)directions are 3.780 and 3.969,respectively.Red shift oc-curs at the starting point where the imaginary part of the dielectric function is not zero,indicating that doping in?duces electrons to transition more easily.