论文标题
关于MN2V1-XCOXGA Heusler合金的完全补偿的铁磁特性的中子衍射和AB启动研究
Neutron diffraction and ab initio studies on the fully compensated ferrimagnetic characteristics of Mn2V1-xCoxGa Heusler alloys
论文作者
论文摘要
在MN2V1-XCOXGA（X = 0，0.25，0.5，0.75，1）上进行了中子衍射和AB启动研究，该Heusler Alloys表现出高TC完全补偿的X = 0.5的较高补偿的铁磁性特征。对中子衍射和从头算的结合分析表明，晶体结构和磁构型无法从X射线衍射和磁性测量中确定。如前所述，中子衍射数据的Rietveld改进证实了MN2VGA和XA结构的MN2COGA结构。 X = 0.25和0.5的合金具有Mn（C）-CO障碍的L21结构。当CO浓度达到0.75时，已经观察到从无序L21到无序Xa的结构过渡。详细的从头算研究还证实了这种结构过渡。 MN2（V1-XCOX）GA中磁矩补偿的原因与较早报道的完全补偿的Ferrimagnet（MNCO）VGA的原因不同。借助中子衍射和AB的初始研究，可以鉴定出无序的L21结构在（Mn（a）-MN（c））和（V-CO）原子配对的铁磁对齐的磁矩之间具有反平行耦合，从而在MN2V1-XCOXGA中获得补偿。
Neutron diffraction and ab initio studies were carried out on Mn2V1-xCoxGa (x=0, 0.25, 0.5, 0.75, 1) Heusler alloys which exhibits high TC fully compensated ferrimagnetic characteristic for x=0.5. A combined analysis of neutron diffraction and ab initio calculations revealed the crystal structure and magnetic configuration which could not be determined from the X-ray diffraction and magnetic measurements. As reported earlier, Rietveld refinement of neutron diffraction data confirmed L21 structure for Mn2VGa and Xa structure for Mn2CoGa. The alloys with x=0.25 and 0.5 possess L21 structure with Mn(C)-Co disorder. As the Co concentration reaches 0.75, a structural transition has been observed from disordered L21 to disordered Xa. Detailed ab initio studies also confirmed this structural transition. The reason for the magnetic moment compensation in Mn2(V1-xCox)Ga was identified to be different from that of the earlier reported fully compensated ferrimagnet (MnCo)VGa. With the help of neutron diffraction and ab initio studies, it is identified that the disordered L21 structure with antiparallel coupling between the ferromagnetically aligned magnetic moments of (Mn(A)-Mn(C)) and (V-Co) atom pairs enables the compensation in Mn2V1-xCoxGa.
