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arXiv · 1208.4917

Single nonmagnetic impurity resonance in FeSe-based 122-type superconductors as a probe for pairing symmetry

Qian-En Wang·Zi-Jian Yao·Fu-Chun Zhang
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Abstract

We study the effect of a single non-magnetic impurity in A$_{y}$Fe$_{2-x}$Se$_{2}$ (A=K, Rb, or Cs) superconductors by considering various pairing states based on a three-orbital model consistent with the photoemission experiments. The local density of states on and near the impurity site has been calculated by solving the Bogoliubov-de Gennes equations self-consistently. The impurity-induced in-gap bound states are found only for attractive impurity scattering potential, as in the cases of doping of Co or Ni, which is characterized by the strong particle-hole asymmetry, in the nodeless $d_{x^2-y^2}$ wave pairing state. This property may be used to probe the pairing symmetry of FeSe-based 122-type superconductors.

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Qian-En Wang, Zi-Jian Yao, Fu-Chun Zhang. 2013-03-22. Single nonmagnetic impurity resonance in FeSe-based 122-type superconductors as a probe for pairing symmetry. https://doi.org/10.1209/0295-5075%2F101%2F57002

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