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+\delta} 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.
@article{arxiv.cond-mat/0210700,
title = {Electron-phonon interaction in n-doped cuprates: an Inelastic X-ray Scattering study},
author = {M. d'Astuto and P. K. Mang and P. Giura and A. Shukla and A. Mirone and M. Krisch and F. Sette and P. Ghigna and M. Braden and M. Greven},
journal= {arXiv preprint arXiv:cond-mat/0210700},
year = {2009}
}
Comments
Proceedings of the SATT11 conference, Vietri sul Mare - Italy (March 2002); accepted for publication on Int. J. Mod. Phys. B