Coherent optical phonon mode oscillations in wurtzite ZnO excited by femtosecond pulses

Abstract

We report on coherent optical phonon oscillations in wurtzite ZnO. The high- and low-frequency E2 modes are excited by the impulsive stimulated Raman scattering, and detected through the electro-optic effect. The dephasing times are measured to be 1.75 and 29.2 ps for the high- and the low-E2 modes, respectively. The dependency of the phonon amplitude on the spectral width of the femtosecond pulses is shown.