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arXiv · 1804.07841

Connection topology of step edge state bands at the surface of a three dimensional topological insulator

Yishuai Xu·Guodong Jiang·Janet Chiu·Lin Miao·Erica Kotta·Yutan Zhang·Rudro R. Biswas·L. Andrew Wray
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Abstract

Topological insulators in the Bi$_2$Se$_3$ family manifest helical Dirac surface states that span the topologically ordered bulk band gap. Recent scanning tunneling microscopy measurements have discovered additional states in the bulk band gap of Bi$_2$Se$_3$ and Bi$_2$Te$_3$, localized at one dimensional step edges. Here numerical simulations of a topological insulator surface are used to explore the phenomenology of edge state formation at the single-quintuple-layer step defects found ubiquitously on these materials. The modeled one dimensional edge states are found to exhibit a stable topological connection to the two dimensional surface state Dirac point.

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Yishuai Xu, Guodong Jiang, Janet Chiu, Lin Miao, Erica Kotta, Yutan Zhang, Rudro R. Biswas, L. Andrew Wray. 2018-04-20. Connection topology of step edge state bands at the surface of a three dimensional topological insulator. https://doi.org/10.1088/1367-2630%2Faacef6

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