Dirac-cone-like surface state in W(110): dispersion, spin texture and photoemission from first principles
Dirac-cone-like surface state in W(110): dispersion, spin texture and photoemission from first principles
复制标题
W(110) 中的狄拉克锥表面态：来自第一原理的色散、自旋织构和光电发射
DOI：
10.1088/1367-2630/15/3/033019
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发表时间：
2013
影响因子：
3.3
通讯作者：
J. Henk
中科院分区：
文献类型：
--
作者：
H. Mirhosseini;M. Flieger;J. Henk
本文报道了钨（110）表面dz2态的理论研究，详细讨论了自旋分辨电子结构和光发射光谱。与最近的实验一致，这种表面态表现出强烈的各向异性色散：在表面布里渊带的——方向上，它呈线性色散，但在——方向上变得平坦。从头算出的自旋织构与模型哈密顿量得到的织构一致；由于双表面对称性和时间反转对称性，面外自旋极化消失。由于表面态的轨道组成，光发射强度敏感地依赖于入射光的偏振。光电子发生平面外自旋极化，这是由于激发过程打破了时间反转对称性。
We report on a theoretical study of a dz2 surface state at the tungsten (110) surface, addressing in detail the spin-resolved electronic structure as well as photoemission spectroscopy. In agreement with recent experiments, this surface state shows a strongly anisotropic dispersion: in the –– direction of the surface Brillouin zone, it disperses linearly but becomes flattened along the –– direction. The ab initio calculated spin texture agrees with the one derived from a model Hamiltonian; due to twofold surface symmetry and time-reversal symmetry, the out-of-plane spin polarization vanishes. The photoemission intensities depend sensitively on the polarization of the incident light, because of the orbital composition of the surface state. The photoelectrons become spin-polarized out-of-plane, which is attributed to breaking the time-reversal symmetry by the excitation process.