Ferromagnetic spin fluctuation in LaFeAsO1-xFx

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.

13 pages, 4 figures

References in corpus (7)

• Superconductivity on the border of weak itinerant ferromagnetism in UCoGe
• Very High Field Two-Band Superconductivity in LaFeAsO_0.89F_0.11
• The ground state of Sr3Ru2O7 revisited; Fermi liquid close to a ferromagnetic instability
• Pairing due to Spin Fluctuations in Layered Organic Superconductors
• Itinerant Ferromagnetism in layered crystals LaCoOX (X = P, As)
• Intrinsic Properties of Stoichiometric LaOFeP
• Possible Pairing Mechanisms of PuCoGa${}_5$ Superconductor

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