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arXiv · 1407.7651

Emergence of Novel Antiferromagnetic Order Intervening between Two Superconducting Phases in LaFe(As_1-x_P_x_)O: 31P-NMR Studies

H. Mukuda·F. Engetsu·T. Shiota·K. T. Lai·M. Yashima·Y. Kitaoka·S. Miyasaka·S. Tajima
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Abstract

We revealed novel phase deagram of Fe-pnictide high-Tc superconductor LaFe(As_{1-x}P_{x})O in wide doping level (0.3<x<1) by P-NMR. Systematic 31P-NMR studies revealed the emergence of the antiferromagnetic ordered phase (AFM-2) in 0.4 < x < 0.7 that intervenes between two superconductivity (SC-1/SC-2) phases. The 31P-NMR Knight shift points to the appearance of the sharp density of states at the Fermi level that is derived from d_{3Z^2?r^2} orbit, which is less relevant with the onset of the SC-2. On the other hand, we remark that the AFM spin fluctuations arising from the interband nesting on the d_{XZ}/d_{YZ} orbits must be a key ingredient for the occurrence of SC around AFM-2.

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H. Mukuda, F. Engetsu, T. Shiota, K. T. Lai, M. Yashima, Y. Kitaoka, S. Miyasaka, S. Tajima. 2014-07-29. Emergence of Novel Antiferromagnetic Order Intervening between Two Superconducting Phases in LaFe(As_1-x_P_x_)O: 31P-NMR Studies. https://doi.org/10.7566/jpsj.83.083702

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