Positron States at Li- and O-adsorbed Fe(001) Ferromagnetic Surfaces Studied by Two-Component Density Functional Theory
Positron States at Li- and O-adsorbed Fe(001) Ferromagnetic Surfaces Studied by Two-Component Density Functional Theory
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DOI：
10.7566/jpsj.85.114703
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发表时间：
2016-10
影响因子：
1.7
通讯作者：
S. Hagiwara;Kazuyuki Watanabe
中科院分区：
文献类型：
--
作者：
S. Hagiwara;Kazuyuki Watanabe
用双组分密度泛函理论研究了吸附Li和O的Fe（001）铁磁表面的正电子态。正电子表面寿命和正电子结合能被发现是敏感的表面结构的变化和吸附原子引起的偶极势垒，这可以理解的正电子密度分布和表面电位。自旋相关的正电子寿命分数是在最高表面的自旋极化分数非常一致，因为在表面的本地化正电子是敏感的表面磁状态。因此，目前的研究结果表明，自旋极化正电子湮没谱可以提取的最外层表面的磁性状态。
The positron states for Li- and O-adsorbed Fe(001) ferromagnetic surfaces are studied by using two-component density functional theory. Positron surface lifetimes and positron binding energies are found to be sensitive to changes in the surface structure and the dipole barrier induced by adatoms, which can be understood by the positron density distribution and surface potential. Spin-dependent positron lifetime fractions are in excellent agreement with spin-polarization fractions at the topmost surface, because the localized positrons at the surface are sensitive to the surface magnetic state. Therefore, the present results show that spin-polarized positron annihilation spectroscopy can extract the outermost surface magnetic state.