Koji Miyamoto,1* Taichi Okuda,1 Henry Wortelen,2 Markus Donath2
1Hiroshima Synchrotron Radiation Center, Hiroshima University, Kagamiyama 2-313, 7390046 Higashi-Hiroshima, Japan
2Physikalisches Institut, Westfälische Wilhelms-Universität Münster, Wilhelm-Klemm-Strasse 10, 28149 Münster, Germany
Nano-Micro Conference, 2017, 1, 01066
Published Online: 31 October 2017 (Abstract)
Topological insulators and Rashba systems with spin-split energy band structure induced by strong spin-orbit interaction have attracted a great attention for the dissipationless spin current transport. The spin orientation of such spin-split state is locked with their crystal momentum and is strongly influenced by the symmetry of surface crystal. However, so-far, most of topological material and Rashba systems are sp-electrons system with C3v point group symmetry . Recently, we have reported spin polarized Dirac-cone surface state on W(110) with C2v symmetry . This surface state is formed by d-electrons and strongly influence by two-fold symmetry: the massless and massive band dispersion along and . Moreover, by model Hamiltonian based on k•p theorem, it have been predicted that the spin-polarized flatten Dirac-cone surface state shows quasi-one dimensional spin texture as shown in Figure 1 . However, there is no evidence for the spin texture on W(110).
In this presentation, we have clarified the spin texture of flatten Dirac-cone surface state on W(110) studied by spin- and angle-resolved photoemission spectroscopy. The observed spin texture is good agreement with our predicted one. This research is the model case of d-electron –based surface state with C2v symmetry. The finding opens a new avenue in the study of d-electrons-based spin texture with C2v symmetry. If I have remaining time enough to talk another symmetry surface of tungsten, I will introduce you.
 M. Z. Hasan; C. L. Kane, Colloquium: Topological insulators. Reviews of Modern Physics. 82, 3045 (2010). doi:10.1103/RevModPhys.82.3045
 K. Miyamoto; A. Kimura; K. Kuroda; T. Okuda; K. Shimada; H. Namatame; M. Taniguchi; M. Donath, Spin-polarized Dirac-cone-like surface state with d character at W(110). Physical Review Letters. 108, 066808 (2012). doi:10.1103/PhysRevLett.108.066808
 K. Miyamoto; A. Kimura; T. Okuda; K. Shimada; H. Iwasawa; H. Hayashi; H. Namatame; M. Taniguchi; M. Donath, Massless or heavy due to two-fold symmetry: Surface-state electrons at W(110). Physical Review B. 86, 161411(R) (2012). doi:10.1103/PhysRevB.86.161411
This article is licensed under a Creative Commons Attribution 4.0 International License. (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.
© The Author(s) 2017