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

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.

arXiv comment4 pages, 3 figures, submitted for SNS2010 conference proceedings

References in corpus (18)

• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs
• A Large Iron Isotope Effect in SmFeAsO1-xFx and Ba1-xKxFe2As2
• Single crystal of superconducting SmFeAsO1-xFy grown at high pressure
• Single crystals of LnFeAsO1-xFx (Ln=La, Pr, Nd, Sm, Gd) and Ba1-xRbxFe2As2: growth, structure and superconducting properties
• 75As NQR/NMR Studies on Oxygen-deficient Iron-based Oxypnictide Superconductors LaFeAsO_{1-y} (y=0,0.25,0.4) and NdFeAsO_{0.6}
• Effects of magnetism and doping on the electron-phonon coupling in BaFe${}_2$As${}_2$
• Doping dependence of the lattice dynamics in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ studied by Raman spectroscopy
• Phonon anomalies in pure and underdoped R{1-x}K{x}Fe{2}As{2} (R = Ba, Sr) investigated by Raman light scattering
• Phonon anomaly in BaFe2As2
• Synthesis, crystal structure, microstructure, transport and magnetic properties of SmFeAsO and SmFeAs(O0.93F0.07)
• Correlated pressure effects on structure and superconductivity in LaFeAsO0.9F0.1
• Lattice Dynamics of LaFeAsO_{1-x}F_{x} and PrFeAsO_{1-y} via Inelastic X-Ray Scattering and First-Principles Calculation
• Phonon Density of States in Nd(O${}_{1-x}$F${}_x$)FeAs
• Anomalous electron-phonon interaction in doped LaOFeAs: a First Principles calculation
• Influence of Magnetism on Phonons in CaFe2As2 Via Inelastic X-ray Scattering
• Inelastic X-ray Scattering Study of superconducting SmFeAs(O${}_{1-x}$F${}_y$) Single Crystals: Evidence for Strong Momentum-Dependent Doping-Induced Renormalizations of Optical Phonons
• The optical phonon spectrum of SmFeAsO