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arXiv · 1110.0695

Inter-layer Superconducting Pairing Induced c-axis Nodal Lines in Iron-based Superconductors

Yuehua Su·Chandan Setty·Ziqiang Wang·Jiangping Hu
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Abstract

A layered superconductor with a full pairing energy gap can be driven into a nodal superconducting (SC) state by inter-layer pairing when the SC state becomes more quasi-3D. We propose that this mechanism is responsible for the observed nodal behavior in a class of iron-based SCs. We show that the intra- and inter-layer pairings generally compete and the gap nodes develop on one of the {\em hole} Fermi surface pockets as they become larger in the iron-pnictides. Our results provide a natural explanation of the c-axis gap modulations and gap nodes observed by angle resolved photoemission spectroscopy. Moreover, we predict that an anti-correlated c-axis gap modulations on the hole and electron pockets should be observable in the $S^{\pm}$-wave pairing state.

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Yuehua Su, Chandan Setty, Ziqiang Wang, Jiangping Hu. 2011-10-04. Inter-layer Superconducting Pairing Induced c-axis Nodal Lines in Iron-based Superconductors. https://doi.org/10.1103/physrevb.85.184517

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