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arXiv · 0901.0719

Superfluid density and penetration depth in Fe-pnictides

A. B. Vorontsov·M. G. Vavilov·A. V. Chubukov
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Abstract

We consider the superfluid density $ρ_s (T)$ in a two-band superconductor with extended s-wave symmetry ($s^+$) in the presence of non-magnetic impurities and apply the results to Fe-pnictides. We show that the behavior of the superfluid density is essentially the same as in an ordinary s-wave superconductor with magnetic impurities. We show that, for moderate to strong inter-band impurity scattering, $ρ_s (T)$ behaves as a power-law $T^n$ with $n\approx 1.6\div2$ over a wide range of $T$. We argue that the power-law behavior is consistent with recent experiments on the penetration depth $λ(T)$ in BaFe$_2$As$_2$, but disagree quantitatively with the data on LaFePO.

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A. B. Vorontsov, M. G. Vavilov, A. V. Chubukov. 2009-03-23. Superfluid density and penetration depth in Fe-pnictides. https://doi.org/10.1103/physrevb.79.140507

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