Presentation Information
[1P22]Electronic states of Bi ultrathin film on Sb studied by ARPES
*Suzuna Inoue1, Shunji Ito1, Masaki Imamura2, Kazutoshi Takahashi2, Akari Takayama1,3 (1. Department of Physics and Applied Physics, Waseda University, 2. Synchrotron Light Application Center, Saga University, 3. Institute of Multidisciplinary Research for Advanced Materials, Tohoku University)
Bismuth (Bi) is known as a typical material that exhibits the Rashba effect, thus there have been so many studies have been conducted in three-dimensional crystals and thin films. Especially, the 1 bilayer Bi ultrathin film is theoretically predicted to be a two-dimensional topological insulator, and its fabrication and understanding of its electronic states are highly desired. In this study, we fabricated Bi ultra-thin films on Sb(111) and measured their electronic states by using angle-resolved photoemission spectroscopy. As a result of the experiment, the X-shaped band was observed to degenerate at the Γ point, with the degeneration point located at a binding energy ~ 0.5 eV. We found that the X-shaped band showed two-dimensional dispersion and differed from the theoretical band dispersion of free-standing 1 bilayer Bi. It suggests that the X-shaped feature may originate from hybridization between the surface electronic states of Bi and Sb.