NaCl型半金属铁磁体CrCa_7Se_8的第一性原理研究  

The First Principles Researches on the NaCl-type Half-metallic Ferromagnet CrCa_7Se_8

作　　者：陈沛达[1] 

机构地区：[1]重庆邮电大学光电学院,中国重庆400065

出　　处：《科技信息》2012年第1期132-134,共3页Science & Technology Information

摘　　要：本文采用基于密度泛函理论的第一性原理研究,优化了具有NaCl结构的CrCa7Se8的几何结构,计算了其自旋极化的电子态密度,电荷分布和离子磁矩等电学和磁学性能,并分析了其电子结构,展望了其在自旋电子学中的应用。研究表明,CrCa7Se8在费米面处具有+100%的自旋极化率,呈现出半金属性,其超胞磁矩为4.00μB,磁矩主要来源于过渡元素Cr。CrCa7Se8具有较宽的自旋带隙和较大的超胞磁矩,可作为自旋半导体材料的优质自旋注入材料。同时,它可能具有较高的居里温度,从而在自旋电子学中具有广泛的应用前景。Cr离子的电子结构为eg2↑t2g2↑。The first principles researches based on the density function theory are performed to optimize the geometric structure of NaCl-type compound CrCaTSes. Their electric and magnetic properties such as the spin-polarized state densities, the charge distributions and the ionic magnetic moments are calculated. Then the electronic structures are analyzed. Their application prospects in the spin electronics are analyzed. From our researches, the spin polarization of CrCa7Se8 at the Fermi level is ＋100%, so it is probably half-metallic ferromagnets. CrCaTSes exhibits a half- metallic characteristic and is suitable for spin injectors. Its supercell magnetic moment is 4.00 μB, which arises mainly from the Cr-ion. CrCaTSes has wide half-metallic gap and then high Curie temperature possibly, which indicates wide application prospects in spintronics. The electronic structures of Cr-ion are Cr：eg2↑t2g2↑ .

关 键 词：半金属铁磁体 自旋半导体 电子结构 超胞磁矩 

分 类 号：O561.2[理学—原子与分子物理]