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arXiv · 1608.02361

Topological surface states on Bi(111) based on empirical tight-binding calculations

Yoshiyuki Ohtsubo·Shin-ichi Kimura
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Abstract

The topological order of single-crystal Bi and its surface states on the (111) surface are studied in detail based on empirical tight-binding (TB) calculations. New TB parameters are presented that are used to calculate the surface states of semi-infinite single-crystal Bi(111), which agree with the experimental angle-resolved photoelectron spectroscopy results. The influence of the crystal lattice distortion is surveyed and a topological phase transition is found that is driven by in-plane expansion. In contrast with the semi-infinite system, the surface-state dispersions on finite-thickness slabs are non-trivial irrespective of the bulk topological order. The role of the interaction between the top and bottom surfaces in the slab is systematically studied, and it is revealed that a very thick slab is required to properly obtain the bulk topological order of Bi from the (111) surface state: above 150 biatomic layers in this case.

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Yoshiyuki Ohtsubo, Shin-ichi Kimura. 2016-08-08. Topological surface states on Bi(111) based on empirical tight-binding calculations. https://doi.org/10.1088/1367-2630%2F18%2F12%2F123015

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