Inelastic x-ray scattering investigations of lattice dynamics in SmFeAsO$_{1-x}$F$_y$ superconductors

M. Le Tacon; T. R. Forrest; Ch. Rüegg; A. Bosak; J. Noffsinger; A. C. Walters; P. Toulemonde; A. Palenzona; N. D. Zhigadlo; J. Karpinski; J. P. Hill; M. Krisch; D. F. McMorrow

doi:10.1016/j.jpcs.2010.10.006

arXiv · 1005.4165

Inelastic x-ray scattering investigations of lattice dynamics in SmFeAsO$_{1-x}$F$_y$ superconductors

M. Le Tacon·T. R. Forrest·Ch. Rüegg·A. Bosak·J. Noffsinger·A. C. Walters·P. Toulemonde·A. Palenzona·N. D. Zhigadlo·J. Karpinski·J. P. Hill·M. Krisch·D. F. McMorrow

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Abstract

We report measurements of the phonon density of states as measured with inelastic x-ray scattering in SmFeAsO$_{1-x}$F$_y$ powders. An unexpected strong renormalization of phonon branches around 23 meV is observed as fluorine is substituted for oxygen. Phonon dispersion measurements on SmFeAsO$_{1-x}$F$_y$ single crystals allow us to identify the 21 meV A$_{1g}$ in-phase (Sm,As) and the 26 meV B$_{1g}$ (Fe,O) modes to be responsible for this renormalization, and may reveal unusual electron-phonon coupling through the spin channel in iron-based superconductors.

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M. Le Tacon, T. R. Forrest, Ch. Rüegg, A. Bosak, J. Noffsinger, A. C. Walters, P. Toulemonde, A. Palenzona, N. D. Zhigadlo, J. Karpinski, J. P. Hill, M. Krisch, D. F. McMorrow. 2010-05-23. Inelastic x-ray scattering investigations of lattice dynamics in SmFeAsO$_{1-x}$F$_y$ superconductors. https://doi.org/10.1016/j.jpcs.2010.10.006

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