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arXiv · 1403.6240

Functional Renormalization Group Analysis of $η$-Pairing in Iron-based Superconductors

Jing Yuan·Jiangping Hu
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Abstract

Using functional renormalization group (FRG) approach, we analyze the $η$ pairing in a five d-orbital model for iron-pncitides. We find that the $η$ pairing between two hole pockets is a leading instability at low energy when the two hole pockets are close to a nesting condition. The result suggests that the system can spontaneously enter into a superconducting state with both normal pairing and $η$ paring and the $η$ pairing is driven by the inter-orbital antiferromagnetic exchange coupling while the normal pairing is driven by the intra-orbital antiferromagnetic ones. An effective model at low energy is proposed to account for the $η$ pairing instability.

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Jing Yuan, Jiangping Hu. 2014-03-25. Functional Renormalization Group Analysis of $η$-Pairing in Iron-based Superconductors. https://arxiv.org/abs/1403.6240

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