Speaker
Description
Tin (Sn) atomic layers attract considerable interest owing to their spin-dependent physical properties caused by their strong spin–orbit interaction. We have studied the spin-dependent band structure in a Sn atomic layer that is intercalated into the graphene/SiC(0001) interface [1] using laser-based spin- and angle-resolved photoemission spectroscopy (laser-SARPES) . We can not only obtain high energy-resolution spectra but also observe spin-dependent quantum interference in the photoemission process [2] with the use of the newly-developed laser-SARPES[3]. In the atomic layer, the Sn atoms occupy on-top sites of the Si-terminated SiC(0001) surface with in-plane Sn–Sn bonding. The graphene overlayer ensures little oxidation upon exposure to air in the Sn atomic layer at the interface. This is useful for ex situ characterization and device fabrication. We find spin-split Sn bands due to the spin-orbit interaction. At K point, two kinds of spin splitting, Rashba and Zeemann types, appear while the crystal symmetry indicates only the Zeemann type [4]. The experimental results are attributed to a novel symmetry of the Sn wave function on the basis of first-principles calculations.
- S. Hayashi, A. Visikovskiy, T. Kajiwara, T. Iimori, T. Shirasawa, K. Nakastuji, T. Miyamachi, S. Nakashima, K. Yaji, K. Mase, F. Komori, and S. Tanaka , Appl. Phys. Exp. 11 (2018) 015202.
- K. Yaji, K. Kuroda, S. Toyohisa, A. Harasawa, Y. Ishida, S. Watanabe, C. Chen, K. Kobayashi, F. Komori and S. Shin, , Nat. Commun. 8 (2017) 14588.
- K. Yaji, A. Harasawa, K. Kuroda, S. Toyohisa, M. Nakayama, Y. Ishida, A. Fukushima, S. Watanabe, C. Chen, F. Komori, and S. Shin, Rev. Sci. Instru. 87 (2016) 053111.
- T. Oguchi, and T. Shishidou, J. Phys.: Condens. Matter 21 (2009) 092001.
