Topological transition in Bi1-xSbx studied as a function of Sb doping

Fumitaka Nakamura , Yuka Kousa , Alexey A. Taskin , Yasuo Takeichi , Akinori Nishide , Akito Kakizaki , Marie d'Angelo (1) , Patrick Lefèvre , François Bertran (2) , Amina Taleb-Ibrahimi (2) , Fumio Komori , Shin-Ichi Kimura , Hiroshi Kondo , Yoichi Ando , Iwao Matsuda

1 INSP - Institut des Nanosciences de Paris
2 SSOLEIL - Synchrotron SOLEIL

Spin- and angle-resolved photoemission spectroscopy measurements were performed on Bi1-xSbx samples at x = 0.04, 0.07, and 0.21 to study the change of the surface band structure from nontopological to topological. Energy shift of the T and L-s bulk bands with Sb concentration is quantitatively evaluated. An edge state becomes topologically nontrivial at x = 0.04. An additional trivial edge state appears at the L band gap that forms at x > 0.04 and apparently hybridize with the nontrivial edge state. A scenario for the topological transition mechanism is presented. Related issues of self-energy and temperature dependence of the surface state are also considered.

Domaines: Matière Condensée [cond-mat]

Fumitaka Nakamura, Yuka Kousa, Alexey A. Taskin, Yasuo Takeichi, Akinori Nishide, et al.. Topological transition in Bi1-xSbx studied as a function of Sb doping. Physical Review B: Condensed Matter and Materials Physics (1998-2015), 2011, 84 (23), pp.235308. ⟨10.1103/PhysRevB.84.235308⟩. ⟨hal-01237364⟩