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arXiv · 1511.02675

Uniform impurity scattering in two-band $s_\pm$ and $s_{++}$ superconductors

M. M. Korshunov·Yu. N. Togushova·O. V. Dolgov
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Abstract

The $s_\pm$ and $s_{++}$ models for the superconducting state are subject of intense studies regarding Fe-based superconductors. Depending on the parameters, disorder may leave intact or suppress $T_c$ in these models. Here we study the special case of disorder with equal values of intra- and interband impurity potentials in the two-band $s_\pm$ and $s_{++}$ models. We show that this case can be considered as an isolated point and $T_c$ there has maximal damping for a wide range of parameters.

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M. M. Korshunov, Yu. N. Togushova, O. V. Dolgov. 2015-11-09. Uniform impurity scattering in two-band $s_\pm$ and $s_{++}$ superconductors. https://doi.org/10.1007/s10948-016-3385-6

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