Lattice dynamics and electron-phonon coupling in Sr2RuO4:: Inelastic neutron scattering and shell-model calculations

The lattice dynamics in Sr2RuO4 has been studied by inelastic neutron scattering combined with shell-model calculations. The in-plane bond-stretching modes in Sr2RuO4 exhibit a normal dispersion in contrast to all electronically doped perovskites studied so far. Evidence for strong electron phonon coupling is found for c-polarized phonons suggesting a close connection with the anomalous c-axis charge transport in Sr2RuO4. The role of this electron-phonon coupling in the superconducting pairing remains, however, a challenging open issue.