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arXiv · 0807.3370

Phonon Density of States of LaFeAsO1-xFx

A. D. Christianson·M. D. Lumsden·O. Delaire·M. B. Stone·D. L. Abernathy·M. A. McGuire·A. S. Sefat·R. Jin·B. C. Sales·D. Mandrus·E. D. Mun·P. C. Canfield·J. Y. Y. Lin·M. Lucas·M. Kresch·J. B. Keith·B. Fultz·E. A. Goremychkin·R. J. McQueeney
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Abstract

We have studied the phonon density of states (PDOS) in LaFeAsO1-xFx with inelastic neutron scattering methods. The PDOS of the parent compound(x=0) is very similar to the PDOS of samples optimally doped with fluorine to achieve the maximum Tc (x~0.1). Good agreement is found between the experimental PDOS and first-principle calculations with the exception of a small difference in Fe mode frequencies. The PDOS reported here is not consistent with conventional electron-phonon mediated superconductivity.

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A. D. Christianson, M. D. Lumsden, O. Delaire, M. B. Stone, D. L. Abernathy, M. A. McGuire, A. S. Sefat, R. Jin, B. C. Sales, D. Mandrus, E. D. Mun, P. C. Canfield, J. Y. Y. Lin, M. Lucas, M. Kresch, J. B. Keith, B. Fultz, E. A. Goremychkin, R. J. McQueeney. 2008-07-22. Phonon Density of States of LaFeAsO1-xFx. https://doi.org/10.1103/physrevlett.101.157004

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