Cr掺杂LiZnAs稀磁半导体的第一性原理研究

采用第一性原理研究了Li过量情况下Cr掺杂LiZnAs体系（Li_1.1（Zn_1-xCr_x）As）（x=0.1） 的稳定构型、磁性来源以及电子结构.首先，通过比较不同构型下Cr掺杂LiZnAs稀磁半导体体系得到稳定构型的能量，发现一定的Li过量、Cr掺杂浓度下，当掺杂的Cr原子之间的初始距离一定时，过剩的Li空位之间的距离对其构型稳定性有较大影响；其次，分析了Cr掺杂LiZnAs的磁性来源，发现其磁性主要来源于Cr原子的3d轨道；最后，研究了Cr掺杂LiZnAs体系的电子结构，结果显示Cr掺杂LiZnAs体系的电子结构具有稀磁半导体特性.

The study of Cr doped LiZnAs diluted semiconductor based on the first-principles

In order to find the stable configuration, origin of magnetism and electronic structure of Cr doped LiZnAs with excess Li system (Li_1.1(Zn_1-xCr_x)As) (x=0.1), the energies of various configurations, the magnetic moment and the total and partial wave electronic density of states on Li_1.1(Zn_1-xCr_x)As (x=0.1) system have been studied based on the first-principles. The stable configuration is found by comparing the energies of various configurations on Li_1.1(Zn_1-xCr_x)As (x=0.1) system. The calculated results also show that when the excess Li and doped Cr are certain, the initial distance between Cr atoms is also certain, the space distance between excess Li has obvious influence on the energies of configurations of (Li_1.1(Zn_1-xCr_x)As) (x=0.1) system, hence on the stability of (Li_1.1(Zn_1-xCr_x)As) (x=0.1) configuration. Secondly, it is found that the magnetic moment of (Li_1.1(Zn_1-xCr_x)As) (x=0.1) system mainly comes from the 3d orbitals of Cr atom according to the calculated results of the total and atom magnetic moment of (Li_1.1(Zn_1-xCr_x)As) (x=0.1) system. Finally, Cr doped LiZnAs is found to have characteristics of the diluted magnetic semiconductor by the study on the electronic structure of Cr doped LiZnAs system.