Full-Heusler合金X_2YGa(X=Co,Fe,Ni;Y=V,Cr,Mn)的电子结构、磁性及半金属特性的第一性原理研究  

First-principles study on the electronic structures,magnetism,and half-metallicity of full-Heusler X_2YGa(X=Co,Fe,Ni;Y=V,Cr,Mn) alloys

作　　者：刘新浩[1] 林景波[1] 刘艳辉[1] 金迎九[1] 

机构地区：[1]延边大学理学院物理系,延吉133002

出　　处：《物理学报》2011年第10期556-562,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:10664005;10864008;11064015);教育部留学回国人员科研启动基金(批准号:[2007]1108)资助的课题~~

摘　　要：利用基于密度泛函理论的全势线性缀加平面波方法,结合广义梯度近似,对full-Heusler X2YGa(X=Co,Fe,Ni;Y=V,Cr,Mn)合金的电子结构、磁性及半金属特性进行了研究,并讨论了自旋-轨道耦合作用对它们的影响.计算结果表明,自旋-轨道耦合作用对full-Heusler X2YGa(X=Co,Fe,Ni;Y=V,Cr,Mn)合金的电子结构,磁性与半金属特性的影响很小.当未考虑自旋-轨道耦合作用时,Co2VGa,Co2CrGa,和Fe2CrGa合金为半金属或准半金属铁磁体,加入自旋-轨道耦合作用后体系的自旋极化率将降低1%左右,它们依然保持很高的自旋极化率.Fe2MnGa,Co2MnGa,Ni2CrGa和Ni2MnGa合金为一般铁磁体,Fe2VGa和Ni2VGa合金为顺磁体.Using the full-potential linearized augmented plane wave method within the generalized gradient approximation,we investigatete the electronic structures,magnetisms and half-metallicities of the full-Heusler X2YGa（X=Co,Fe,Ni;Y=V,Cr,Mn） alloys.It is found that the spin-orbit coupling has little effect on the electronic structures,magnetisms and half-metallicities of the full-Heusler X2YGa（X=Co,Fe,Ni;Y=V,Cr,Mn） alloys.Without spin-orbit coupling the Co2VGa,Co2CrGa,and Fe2CrGa alloys are half-metallic or nearly half-metallic ferromagnets.With including the spin-orbit coupling,the spin-polarizations are lowered by about 1%,thus they still remain high spin-polarizations.The Fe2MnGa,Co2MnGa,Ni2CrGa,and Ni2MnGa alloys are conventional ferromagnets,whereas the Fe2VGa and Ni2VGa alloys are paramagnets.

关 键 词：半金属特性 自旋-轨道耦合 HEUSLER合金 全势线性缀加平面波方法(FLAPW) 

分 类 号：O471.1[理学—半导体物理]