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arXiv · 1507.05904

Edge states and local electronic structure around an adsorbed impurity in a topological superconductor

Yuan-Yen Tai·Hongchul Choi·Towfiq Ahmed·C. S. Ting·Jian-Xin Zhu
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Abstract

Recently topological superconducting states has attracted a lot of interest. In this work, we consider a topo- logical superconductor with $Z_2$ topological mirror order [1] and s$\pm$-wave superconducting pairing symmetry, within a two-orbital model originally designed for iron-based superconductivity [2]. We predict the existence of gapless edge states. We also study the local electronic structure around an adsorbed interstitial magnetic impurity in the system, and find the existence of low-energy in-gap bound states even with a weak spin polar- ization on the impurity. We also discuss the relevance of our results to the recent STM experiment on Fe(Te,Se) compound with adsorbed Fe impurity [3], for which our density functional calculations show the Fe impurity is spin polarized.

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Yuan-Yen Tai, Hongchul Choi, Towfiq Ahmed, C. S. Ting, Jian-Xin Zhu. 2015-07-21. Edge states and local electronic structure around an adsorbed impurity in a topological superconductor. https://doi.org/10.1103/physrevb.92.174514

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