Mikhail V. Kuznetsov, Lada V. Yashina, Jaime Sánchez-Barriga, Ilya I. Ogorodnikov, Andrey S. Vorokh, Andrey A. Volykhov, Roland J. Koch, Vera S. Neudachina, Marina E. Tamm, Anna P. Sirotina, Andrei Yu. Varykhalov, Gunther Springholz, Günther Bauer, John D. Riley, and Oliver Rader
Phys. Rev. B, V. 91, P. 085402.
DOI
ABSTRACT. Understanding how topologically protected surface states behave at surfaces and interfaces requires knowledge of the atomic structure. Whether the (111) surfaces of the prototypical topological insulators Bi
2Se
3 and Bi
2Te
3 are Bi or chalcogen terminated is the subject of current controversies. We employ photoelectron diffraction and holography, combining the advantages and avoiding the disadvantages of the contesting techniques previously used. We find bulklike chalcogen termination with a very small surface relaxation (<1%) in agreement with density functional theory simulations. We prove the chalcogen termination for cleaved crystals and epitaxial films which shows the robustness of our conclusions.