The temperature dependence of the LO(T) and TO(T) phonons in GaAs and InP

Abstract The LO and TO phonon frequencies and dampings have been measured by near‐infrared Raman spectroscopy both in bulk GaAs and InP. The phonon damping of the LO phonon in InP is much smaller than the LO phonon damping in GaAs. The experimentally obtained temperature dependences were compared with a theory including cubic anharmonic processes and the thermal expansion of the lattice. It is shown that the phonon damping is mainly affected by decay processes into acoustic phonons.