TIME-RESOLVED RAMAN STUDIES OF THE DECAY OF THE LONGITUDINAL OPTICAL PHONONS IN WURTZITE GAN

Decay of the longitudinal-optical (LO) phonons in wurtzite GaN has bee n studied by subpicosecond time-resolved Raman spectroscopy. Our exper imental results show that among the various possible decay channels, t he LO phonons in wurtzite GaN decay primarily into a large wave-vector TO and a large wave-vector LA or TA phonon. These experimental result s an consistent with the recent theoretical calculations of the phonon dispersion curves for wurtzite GaN. (C) 1998 American Institute of Ph ysics.