Heyen E.T., Rashkeev S.N., Mazin I.I., Andersen O.K., Liu R., Cardona M., Jepsen O.
The authors have measured and calculated the dependence of the Raman phonon intensities of YBa2Cu3O7 on laser frequency. The local-density approximation and the linear muffin-tin-orbital method were used for the calculations. They find good agreement not only in the absolute phonon intensities in zz or xx/yy polarization but also in the shape of the resonance profiles. These results indicate that the local-density approximation gives an essentially correct description of the band structure and of the electron-phonon interaction +or-2 eV around the Fermi energy. They interpret the data in terms of specific interband transitions and estimate the mode mixing.
Max-Planck Institut für Festkörperforschung; Postfach 80 06 65 D-70506 Stuttgart |