In systems with orbital order there is an elementary excitation, orbiton, due to the breaking of orbital symmetry. It is shown that there is both a correlation and dynamical lattice contribution to the orbital excitation, which makes the orbiton an intrinsically mixed mode. A localized model calculation shows that in the phonon excitation spectrum weak satellites appear at the orbiton energy, in qualitative agreement with Raman experiments on LaMnO3.
- Raman scattering
- Orbital excitation