A theoretical model explaining the nonradiative energy transfer from a photoexcited impurity ion into the lattice in a laser crystal is presented. The energy-transfer mechanism consists of electronic energy transfer to local vibrations that then dissipate their energy to lattice (phonon) modes of the same energy creating a nonequilibrium phonon population. The model explains the experimental temporal profiles of nonequilibrium optical phonons probed by time-resolved Raman scattering in Cr-doped forsterite laser crystal. The electronic transition time and relaxation lifetimes for phonon and for local modes are ∼3, 4, and 8 ps, respectively.
|Original language||English (US)|
|Number of pages||8|
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|State||Published - Dec 1 1997|
ASJC Scopus subject areas
- Condensed Matter Physics