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arXiv · 1406.5339

Coexistence of Antiferromagnetism and Superconductivity in Iron-Based Superconductors

Yasunori Matsui·Takao Morinari·Takami Tohyama
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Abstract

We theoretically investigate the coexistence of antiferromagnetism and superconductivity in the iron-based superconductors by using the mean-field theory for two- and three-orbital models. We find that both the s_{+-}-wave and s_{++}-wave superconductivity can coexist with antiferromagnetism in the two models. On Dirac Fermi surfaces emerging in the antiferromagnetic phase, a superconducting-gap function has a node for s_{++} wave but is nodeless for s_{+-} wave. On the other hand, the gap function on non-Dirac Fermi surfaces is either nodeless or accidentally nodal, depending on the parameters of pairing interaction, which is independent of pairing symmetry.

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Yasunori Matsui, Takao Morinari, Takami Tohyama. 2014-06-20. Coexistence of Antiferromagnetism and Superconductivity in Iron-Based Superconductors. https://doi.org/10.7566/jpsj.83.094703

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