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arXiv · 1305.3558

Termination dependent topological surface states of the natural superlattice phase Bi$_4$Se$_3$

Q. D. Gibson·L. M. Schoop·A. P. Weber·Huiwen Ji·S. Nadj-Perge·I. K. Drozdov·H. Beidenkopf·J. T. Sadowski·A. Fedorov·A. Yazdani·T. Valla·R. J. Cava
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Abstract

We describe the topological surface states of Bi$_4$Se$_3$, a compound in the infinitely adaptive Bi$_2$-Bi$_2$Se$_3$ natural superlattice phase series, determined by a combination of experimental and theoretical methods. Two observable cleavage surfaces, terminating at Bi or Se, are characterized by angle resolved photoelectron spectroscopy and scanning tunneling microscopy, and modeled by ab-initio density functional theory calculations. Topological surface states are observed on both surfaces, but with markedly different dispersions and Kramers point energies. Bi$_4$Se$_3$ therefore represents the only known compound with different topological states on differently terminated surfaces.

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Q. D. Gibson, L. M. Schoop, A. P. Weber, Huiwen Ji, S. Nadj-Perge, I. K. Drozdov, H. Beidenkopf, J. T. Sadowski, A. Fedorov, A. Yazdani, T. Valla, R. J. Cava. 2013-11-08. Termination dependent topological surface states of the natural superlattice phase Bi$_4$Se$_3$. https://doi.org/10.1103/physrevb.88.081108

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