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arXiv · 1002.3358

Nodes in the Gap Function of LaFePO, the Gap Function of the Fe(Se,Te) Systems, and the STM Signature of the s$_{\pm}$ Pairing

Fa Wang·Hui Zhai·Dung-Hai Lee
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Abstract

We reiterate, in more details, our previous proposal of using quasi-particle interference to determine the pairing form factor in iron-based superconductors. We also present our functional renormalization group(FRG) results on LaFePO and Fe(Se,Te) superconductors. In particular we found that the leading pairing channel in LaFePO is nodal s$_{\pm}$, with nodes on electron Fermi surfaces. For Fe(Se,Te) system we found fully gapped s$_{\pm}$ pairing, with substantial gap anisotropy on electron Fermi surfaces, and large gap is concentrated in regions with dominant $xy$ orbital character. We further fit the form factor obtained by FRG to real space orbital basis pairing picture, which shows more clearly the differences between different iron-based superconductors.

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Fa Wang, Hui Zhai, Dung-Hai Lee. 2010-05-07. Nodes in the Gap Function of LaFePO, the Gap Function of the Fe(Se,Te) Systems, and the STM Signature of the s$_{\pm}$ Pairing. https://doi.org/10.1103/physrevb.81.184512

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