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

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 نشر من قبل Yuan-Yen Tai
 تاريخ النشر 2015
  مجال البحث فيزياء
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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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