论文部分内容阅读
窄带隙半导体异质结构的自旋效应最近受到了国际上的很大关注.Ⅳ-Ⅵ族半导体具有各向异性和多能谷的特征,因此可以预期Rashba自旋效应在不同取向的Ⅳ-Ⅵ族半导体量子阱结构中存在显著差异.计算了多个取向的Pb1-y SryTe/PbTe/Pb1-x SrxTe非对称量子阱中的Rashba分裂能,结果表明[100]取向的PbTe量子阱的Rashba分裂能在阱宽为5.0nm时高达2.2meV,而沿其他两个主要方向([110],[111])生长的量子阱由于能谷的退简并存在两组Rashba分裂能.给出了Rashba自旋分裂能与量子阱非对称参量、阱宽、温度和波矢k∥的依赖关系.Ⅳ-Ⅵ族半导体非对称量子阱结构比Ⅲ-Ⅴ族半导体具有更大的Rashba自旋分裂能,这一特点使得它在自旋电子器件领域可能具有潜在的应用价值.
Recently, the spin-effect of narrow-band semiconductor heterostructures has received much attention in the world. The IV-VI semiconductors have the characteristics of anisotropy and multi-energy valley. Therefore, it is expected that the spin-effect of Rashba in different orientation IV- Ⅵ The results show that the Rashba cleavage energy of the [100] -oriented PbTe quantum well is higher than that of the Pb-based quantum well Can reach as high as 2.2 meV at a well width of 5.0 nm, while the quantum wells grown in the other two main directions ([110], [111]) have two groups of Rashba splitting energies due to the degeneracy of the valleys. The spin-splitting energy can be related to the asymmetry parameters of quantum well, well width, temperature and wave vector k∥. The IV-Ⅵ semiconductor asymmetric quantum well structure has larger Rashba spin splitting energy than the III-V semiconductor, This feature makes it possible in the field of spintronic devices has potential applications.