We measured the Stokes to anti-Stokes intensity ratio in the phonon Raman spectrum of a rutile (TiO2) crystal. We found that although the ratio still equals the Boltzmann factor at the center frequency ω0 of a mode, it deviates from the Boltzmann factor by up to 5% and approaches a constant value of ehω0/kBT within the spectrally-broadened region. It is suggested that irreversible dissipation is essential to understanding this deviation and the broadening of the phonon mode. © 2011 Published by Elsevier B.V.
Watanabe, J., & Kinoshita, S. (2011). Spectral broadening in phonon Raman scattering and its stokes to anti-stokes intensity ratio. In Physics Procedia (Vol. 13, pp. 50–53). Elsevier B.V. https://doi.org/10.1016/j.phpro.2011.02.012