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arXiv · 0803.2528

Electron Correlations in the Low Carrier Density LaFeAsO0.89F0.11 Superconductor (Tc = 28 K)

Athena S. Sefat·Michael A. McGuire·Brian C. Sales·Rongying Jin·Jane Y. Howe·David Mandrus
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Abstract

The crystal structure and numerous normal and superconducting state properties of layered tetragonal (P4/nmm) LaFeAsO, with F-doping of 11 %, are reported. Resistivity measurements give an onset transition temperature Tc = 28.2 K, and low field magnetic susceptibility data indicate bulk superconductivity. In applied magnetic field, analysis of the resistive transition results in a critical field Hc2 = 30 T and a coherence length 35 A. An upper limit for the electron carrier concentration of 1 x 10^21 cm-3 is inferred from Hall data just above Tc. Strong electron-electron correlations are suggested from temperature-dependent resistivity, Seebeck coefficient, and thermal conductivity data. Anomalies near Tc are observed in both Seebeck coefficient and thermal conductivity data.

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Athena S. Sefat, Michael A. McGuire, Brian C. Sales, Rongying Jin, Jane Y. Howe, David Mandrus. 2008-03-17. Electron Correlations in the Low Carrier Density LaFeAsO0.89F0.11 Superconductor (Tc = 28 K). https://doi.org/10.1103/physrevb.77.174503

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