Impurities in multiband superconductors

Abstract

Disorder - impurities and defects violating an ideal order - is always present in solids. It can result in interesting and sometimes unexpected effects in multiband superconductors. Especially if the superconductivity is unconventional thus having other than the usual s-wave symmetry. This paper uses the examples of iron-based pnictides and chalcogenides to examine how both nonmagnetic and magnetic impurities affect superconducting states with $s_{\pm }$ and $s_{++}$ order parameters. We show that disorder causes the transitions between $s_{\pm }$ and $s_{++}$ states and examine observable effects these transitions can produce.

Review article, 46 pages (English version of Usp. Fiz. Nauk 186, 1315 (2016), see http://ufn.ru/en/articles/2016/12/c/)

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Cited by in corpus (25)

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• Superconductivity in Cu-doped Bi${}_2$Se${}_3$ with potential disorder
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• In-plane p-wave coherence length in iron-based superconductors
• Theory of potential impurity scattering in pressurized superconducting La${}_3$Ni${}_2$O${}_7$
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• Unusually weak irradiation effects in anisotropic iron-based superconductor RbCa2Fe4As4F2
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