[1P01-52] Poster Presentation

[1P10] Angle-resolved photoemission study of ultra-flat bismuthene grown on Ag(111)

*Kazutoshi Takahashi¹, Masaki Imamura¹, Haruto Ikeda¹, Ryosuke Koyama¹, Isamu Yamamoto¹, Junpei Azuma¹ (1. Synchrotron Light Application Center, Saga University)

The electronic structure of ultraflat hexagonal bismuthene with a (2×2) superstructure grown on an Ag(111) surface was elucidated via photoemission spectroscopy using synchrotron radiation. The asymmetry of the Bi core level of (2×2) surface was smaller than that of the (√3×√3) surface alloy, indicating that the interaction between the Ag sp and Bi sp states on (2×2)-Bi surface is small. The band structure of (2×2)-Bi on Ag(111) did not change when the thickness of the Ag layers was decreased to 4 ML, indicating that the penetration of Bi p-orbitals into the Ag layer was small. The band structure of (2×2)-Bi showed excellent agreement with the band calculation of ultraflat bismuthene, where Bi p_xy orbitals resulted in a large topological gap of approximately 1.4 eV at the K point.