Abstract
We report on Raman scattering measurements of single crystalline (, 0.06, 0.09, and 0.125), focusing on the high-frequency regime. We observe multiphonon scattering processes up to fourth order which show distinct features: (i) anomalies in peak energy and its relative intensity and (ii) a pronounced temperature, polarization, and doping dependence. These features suggest a mixed orbiton-phonon nature of the observed multiphonon Raman spectra.
- Received 14 December 2004
DOI:https://doi.org/10.1103/PhysRevB.72.024301
©2005 American Physical Society