Sudden gap closure across the topological phase transition in Bi2-xInxSe3

Article

关键词: SINGLE DIRAC CONE;    INSULATOR;    SURFACE;    TEXTURE;    BI2SE3;    STATES;    BI2TE3;   

DOI  :  10.1103/PhysRevB.92.115150

来源: SCIE

【 摘 要 】

The phase transition from a topological insulator to a trivial band insulator is studied using angle-resolved photoemission spectroscopy on Bi2-xInxSe3 single crystals. We first report the complete evolution of the bulk band structures throughout the transition. The robust surface state and the bulk-gap size (similar to 0.50 eV) show no significant change upon doping for x = 0.05, 0.10, and 0.175. At x >= 0.225, the surface state completely disappears and the bulk-gap size increases, suggesting a sudden gap closure and topological phase transition around x similar to 0.175-0.225. We discuss the underlying mechanism of the phase transition, proposing that it is governed by the combined effect of spin-orbit coupling and interactions upon band hybridization. Our study provides a venue to investigate the mechanism of the topological phase transition induced by nonmagnetic impurities.

【 授权许可】

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