Temperature dependence of Raman linewidth and shift in CuI

The temperature dependence of the optical phonon linewidth and frequency shift in CuI has been measured in the temperature range of 4.2 ～ 300 K. Utilizing phonon dispersion curves obtained from neutron scattering measurements, the linewidths and frequency shifts are calculated in terms of three-phonon interactions proposed by Pine and Tannenwald. The experimental results for the change in linewidth and frequency with temperature are in good agreement with this theory.