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arXiv · 0806.3304

Ferromagnetic spin fluctuation in LaFeAsO1-xFx

Yoshimitsu Kohama·Yoichi Kamihara·Masahiro Hirano·Hitoshi Kawaji·Tooru Atake·Hideo Hosono
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Abstract

The F doped LaFeAsO, a recently discovered superconductor with the high Tc of 26 K, has been studied by the resistivity, magnetic susceptibility, and heat capacity measurements in the F doping range from 0 to 0.14 (x in LaFeAsO1-xFx). In the low temperature region, a T3lnT term in the heat capacity and a T2 term in the magnetic susceptibility, which are derived from the spin fluctuation, are observed. The nearly ferromagnetic nature evidenced by a large Wilson ratio (6.5 for x = 0, and 11.2 for x = 0.025) suggests that the superconductivity in the LaFeAsO system is mediated by ferromagnetic spin fluctuation.

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Yoshimitsu Kohama, Yoichi Kamihara, Masahiro Hirano, Hitoshi Kawaji, Tooru Atake, Hideo Hosono. 2008-06-20. Ferromagnetic spin fluctuation in LaFeAsO1-xFx. https://doi.org/10.1103/physrevb.78.020512

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