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Anomalous Dispersion of Longitudinal Optical Phonons in $\mathrm{\mathbf{Nd_{1.86}Ce_{0.14}CuO_{4+\bmδ}}}$ Determined by Inelastic X-ray Scattering

M. d'Astuto·P. K. Mang·P. Giura·A. Shukla·P. Ghigna·A. Mirone·M. Braden·M. Greven·M. Krisch·F. Sette
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Abstract

The phonon dispersions of $\mathrm{Nd_{1.86}Ce_{0.14}CuO_{4+δ}}$ along the $[ξ,0,0]$ direction have been determined by inelastic x-ray scattering. Compared to the undoped parent compound, the two highest longitudinal phonon branches, associated with the Cu-O bond-stretching and out-of-plane oxygen vibration, are shifted to lower energies. Moreover, an anomalous softening of the bond-stretching band is observed around $\mathbf{q}=(0.2,0,0)$. These signatures provide evidence for strong electron-phonon coupling in this electron-doped high-temperature superconductor.

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M. d'Astuto, P. K. Mang, P. Giura, A. Shukla, P. Ghigna, A. Mirone, M. Braden, M. Greven, M. Krisch, F. Sette. 2002-01-28. Anomalous Dispersion of Longitudinal Optical Phonons in $\mathrm{\mathbf{Nd_{1.86}Ce_{0.14}CuO_{4+\bmδ}}}$ Determined by Inelastic X-ray Scattering. https://doi.org/10.1103/physrevlett.88.167002

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