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arXiv · 0806.1986

Nodal Superconductivity with Multiple Gaps in SmFeAsO$_{0.9}$F$_{0.1}$

Yonglei Wang·Lei Shan·Lei Fang·Peng Cheng·Cong Ren·Hai-Hu Wen
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Abstract

We report the observation of two gaps in the superconductor SmFeAsO$_{0.9}$F$_{0.1}$ (F-SmFeAsO) with $T_c=51.5K$ as measured by point-contact spectroscopy. Both gaps decrease with temperature and vanish at $T_c$ and the temperature dependence of the gaps are described by the theoretical prediction of the Bardeen-Cooper-Schrieffer (BCS) theory. A zero-bias conductance peak (ZBCP) was observed, indicating the presence of Andreev bound states at the surface of F-SmFeAsO. Our results strongly suggest an unconventional nodal superconductivity with multiple gaps in F-SmFeAsO.

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Yonglei Wang, Lei Shan, Lei Fang, Peng Cheng, Cong Ren, Hai-Hu Wen. 2008-08-07. Nodal Superconductivity with Multiple Gaps in SmFeAsO$_{0.9}$F$_{0.1}$. https://doi.org/10.1088/0953-2048%2F22%2F1%2F015018

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