Reduced surface magnetization of NiMnSb(001)
Reduced surface magnetization of NiMnSb(001)
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NiMnSb(001) 表面磁化强度降低
DOI：
10.1103/physrevb.72.104415
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发表时间：
2005
影响因子：
3.7
通讯作者：
M. Donath
中科院分区：
文献类型：
--
作者：
H. Kolev;G. Rangelov;J. Braun;M. Donath
用自旋分辨出现势谱研究了铁磁半Heusler合金NiMnSb（001）面的自旋相关电子结构。这种表面敏感的技术提供了访问的自旋和元素分辨的局部密度的未占用状态，因此，探针的自旋极化以上的费米能级。结合低能电子衍射和磁光克尔效应测量，我们表征了样品的晶体结构，电子结构和磁性。我们的光谱实验伴随着定量的理论分析。理论上的外观电位谱是基于自洽的电子结构的结果为散装。它们是在完全相对论性框架中作为矩阵元素加权的轨道分辨未占态密度的自卷积而获得的。自旋不对称性的实验结果，从表面区域获得的，被发现显着减少相比，基于体电子结构的NiMnSb的计算。表面磁化强度降低的可能原因进行了讨论。
The spin-dependent electronic structure at the (001) surface of the ferromagnetic half-Heusler alloy NiMnSb has been investigated by spin-resolved appearance potential spectroscopy. This surface-sensitive technique provides access to the spin- and element-resolved local density of unoccupied states and, therefore, probes the spin polarization above the Fermi level. In combination with low-energy electron diffraction and magneto-optical Kerr effect measurements, we characterized the sample with respect to its crystal structure, electronic structure, and magnetic properties. Our spectroscopic experiments were accompanied by a quantitative theoretical analysis. The theoretical appearance potential spectra are based on self-consistent electronic structure results for the bulk. They have been obtained in a fully relativistic framework as a self-convolution of the matrix element-weighted, orbitally resolved unoccupied density of states. The spin asymmetry in the experimental results, obtained from the surface region, is found to be significantly reduced compared with the calculations based on the bulk electronic structure of NiMnSb. Possible reasons for the reduced surface magnetization are discussed.