Band-theoretical prediction of magnetic anisotropy in uranium monochalcogenides
Band-theoretical prediction of magnetic anisotropy in uranium monochalcogenides
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单硫族化铀磁各向异性的能带理论预测
DOI：
10.1103/physrevb.62.11747
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发表时间：
2000
影响因子：
3.7
通讯作者：
H. University
中科院分区：
文献类型：
--
作者：
T. Shishidou;Tamio Oguchi Jst;H. University
在局域自旋密度近似下，采用完全相对论自旋极化能带结构计算方法，研究了USU、USE和UTE三种铀族化合物的磁各向异性。结果表明，磁各向异性的大小较大(约为10 meV/单位公式)，与实验相当。从赝隙形成的角度讨论了这种强各向异性，其关键成分是U5f态的交换分裂以及它们与硫族p态的杂化(f-p杂化)。各向异性的反常趋势在系列(US>；>；Use<；Ute)中被发现，并被解释为U5f态的局域化和f-p杂化之间的竞争。正是硫族p态上的自旋-轨道相互作用对UTE中f-p杂化强度的增大起到了至关重要的作用，导致了磁各向异性的反常系统趋势。
Magnetic anisotropy of uranium monochalcogenides, US, USe and UTe, is studied by means of fully-relativistic spin-polarized band structure calculations within the local spin-density approximation. It is found that the size of the magnetic anisotropy is fairly large (about 10 meV/unit formula), which is comparable with experiment. This strong anisotropy is discussed in view of a pseudo-gap formation, of which crucial ingredients are the exchange splitting of U 5f states and their hybridization with chalcogen p states (f-p hybridization). An anomalous trend in the anisotropy is found in the series (US>>USe<UTe) and interpreted in terms of competition between localization of the U 5f states and the f-p hybridization. It is the spin-orbit interaction on the chalcogen p states that plays an essential role in enlarging the strength of the f-p hybridization in UTe, leading to an anomalous systematic trend in the magnetic anisotropy.