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Electron-phonon interaction in n-doped cuprates: an Inelastic X-ray Scattering study

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

Inelastic x-ray scattering (IXS) with very high (meV) energy resolution has become a valuable spectroscopic tool, complementing the well established coherent inelastic neutron scattering (INS) technique for phonon dispersion investigations. In the study of crystalline systems IXS is a viable alternative to INS, especially in cases where only small samples are available. Using IXS, we have measured the phonon dispersion of Nd_{1.86}Ce_{0.14}CuO_{4+δ} along the [x,0,0] and [x,x,0] in-plane directions. Compared to the undoped parent compound, the two highest longitudinal optical (LO) phonon branches are shifted to lower energies because of Coulomb-screening effects brought about by the doped charge carriers. An additional anomalous softening of the highest branch is observed around q=(0.2,0,0). This anomalous softening, akin to what has been observed in other compounds, provides evidence for a strong electron-phonon coupling in the electron-doped high-temperature superconductors.

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M. d'Astuto, P. K. Mang, P. Giura, A. Shukla, A. Mirone, M. Krisch, F. Sette, P. Ghigna, M. Braden, M. Greven. 2002-10-31. Electron-phonon interaction in n-doped cuprates: an Inelastic X-ray Scattering study. https://doi.org/10.1142/s0217979203016133

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