Phonon density of states of LaFeAsO(1-x)Fx.
We have studied the phonon density of states (PDOS) in LaFeAsO(1-x)Fx 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 approximately 0.1). Good agreement is found between the experimental PDOS and first-principles 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.
Christianson
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Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA.
Lumsden
M D
MD
Delaire
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O
Stone
M B
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Abernathy
D L
DL
McGuire
M A
MA
Sefat
A S
AS
Jin
R
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Sales
B C
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Mandrus
D
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Mun
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Canfield
P C
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Lin
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Lucas
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Kresch
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Keith
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Fultz
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Goremychkin
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McQueeney
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