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arXiv · 0803.0429

LaFeAsO$_{1-x}$F$_x$: A low carrier density superconductor near itinerant magnetism

D. J. Singh·M. H. Du
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Abstract

Density functional studies of 26K superconducting LaFeAs(O,F) are reported. We find a low carrier density, high density of states, $N(E_F)$ and modest phonon frequencies relative to $T_c$. The high $N(E_F)$ leads to proximity to itinerant magnetism, with competing ferromagnetic and antiferromagnetic fluctuations and the balance between these controlled by doping level. Thus LaFeAs(O,F) is in a unique class of high $T_c$ superconductors: high $N(E_F)$ ionic metals near magnetism.

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D. J. Singh, M. H. Du. 2008-06-13. LaFeAsO$_{1-x}$F$_x$: A low carrier density superconductor near itinerant magnetism. https://doi.org/10.1103/physrevlett.100.237003

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