论文标题
L1 $ _0 $ FENI的电子相关效果和局部磁矩
Electronic correlation effects and local magnetic moments in L1$_0$ phase of FeNi
论文作者
论文摘要
我们通过使用密度功能和动态均值场理论的组合来研究feni的L1 $ _0 $相位的电子和磁性。尽管L1 $ _0 $ feni具有略有四扭曲的FCC晶格，但我们发现其组成fe原子的磁性特性与纯BCC Fe中的磁性特性相似。特别是，我们的结果表明，由于Hund的交换而形成的FE位置上存在良好的磁矩。同时，NI站点的磁性更加流动。与纯BCC FE类似，发现Fe $ 3D $状态的自我能源显示出非fermi-liquid行为。这可以通过Fe $ 3D $状态密度的特殊性来解释，该密度在费米级别接近峰值。我们对粒子孔气泡的局部自旋相关功能和动量依赖性的研究表明，该物质中的磁交换预计为Rkky型，铁状态提供局部矩贡献，而与镍位点相对应的状态（包括虚拟的跳动到铁地点），提供迭代剂的贡献。
We study the electronic and magnetic properties of L1$_0$ phase of FeNi, a perspective rare-earth-free permanent magnet, by using a combination of density functional and dynamical mean-field theory. Although L1$_0$ FeNi has a slightly tetragonally distorted fcc lattice, we find that magnetic properties of its constituent Fe atoms resemble those in pure bcc Fe. In particular, our results indicate the presence of well-localized magnetic moments on Fe sites, which are formed due to Hund's exchange. At the same time, magnetism of Ni sites is much more itinerant. Similarly to pure bcc Fe, the self-energy of Fe $3d$ states is found to show the non-Fermi-liquid behavior. This can be explained by peculiarities of density of Fe $3d$ states, which has pronounced peaks near the Fermi level. Our study of local spin correlation function and momentum dependence of particle-hole bubble suggests that the magnetic exchange in this substance is expected to be of RKKY-type, with iron states providing local-moment contribution, and the states corresponding to nickel sites (including virtual hopping to iron sites) providing itinerant contribution.
