The frequency and linewidth of the Raman-activated longitudinal optical (LO) phonons was measured as a function of temperature in the compounds GaAs and AlAs. The low-temperature lifetime of the LO phonon in AlAs and GaAs were found to be 9.7 ps and 9.5 ps respectively, which contradicted earlier predictions. The theoretical and experimental results showed agreement when the accidental degeneracy between the AlAs LO phonon frequency and a feature in the two-phonon density of states was taken into account.
ASJC Scopus subject areas
- Physics and Astronomy(all)