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arXiv · 1104.2923

Relation between 2Delta/Tc and nodes in Fe-based superconductors

Saurabh Maiti·Andrey V. Chubukov
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Abstract

We analyze the interplay between the absence or presence of the nodes in the superconducting gap along electron Fermi surfaces (FSs) in Fe-pnictides, and 2Delta/T_c along hole FSs, measured by ARPES. We solve the set of coupled gap equations for 4-band and 5-band models of Fe-pnictides and relate the presence of the nodes to 2\Delta/T_c being below a certain threshold. Using ARPES data for 2\Delta/T_c, we find that optimally doped (BaK)Fe_2As_2 and Ba(FeCo)_2As_2 and likely nodeless, but iso-valent BaFe_2(AsP)_2 likely has nodes.

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Saurabh Maiti, Andrey V. Chubukov. 2011-04-14. Relation between 2Delta/Tc and nodes in Fe-based superconductors. https://arxiv.org/abs/1104.2923

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