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arXiv · 1202.5303

Surface states on a topologically non-trivial semimetal: The case of Sb(110)

Marco Bianchi·Dandan Guan·Anna Strozecka·Celia H. Voetmann·Shining Bao·Jose Ignacio Pascual·Asier Eiguren·Philip Hofmann
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Abstract

The electronic structure of Sb(110) is studied by angle-resolved photoemission spectroscopy and first-principle calculations, revealing several electronic surface states in the projected bulk band gaps around the Fermi energy. The dispersion of the states can be interpreted in terms of a strong spin-orbit splitting. The bulk band structure of Sb has the characteristics of a strong topological insulator with a Z2 invariant nu0=1. This puts constraints on the existence of metallic surface states and the expected topology of the surface Fermi contour. However, bulk Sb is a semimetal, not an insulator and these constraints are therefore partly relaxed. This relation of bulk topology and expected surface state dispersion for semimetals is discussed.

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Marco Bianchi, Dandan Guan, Anna Strozecka, Celia H. Voetmann, Shining Bao, Jose Ignacio Pascual, Asier Eiguren, Philip Hofmann. 2012-02-23. Surface states on a topologically non-trivial semimetal: The case of Sb(110). https://doi.org/10.1103/physrevb.85.155431

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