Manifestation of Hot Phonons in the Luminescence Spectra of Highly Photoexcited A^IIB^VI Crystals

Abstract

Abstract The quasi‐stationary and transient spectra of the nonequilibrium electron‐hole plasma (EHP) emission are investigated in CdSe crystals. A broadening of the low‐energy side of the luminescence band due to the heating of longitudinal‐optical (LO) phonons is established. A slow stage of the EHP energy relaxation with a time constant of 150 ps is observed and referred to the accumulation of decay products of nonequilibrium LO phonons in the narrow interval of the k ‐space. A model of the two‐stage relaxation of the phonon subsystem in a photoexcited semiconductor is used to calculate the power of energy‐loss in hot EHP and the nonequilibrium LO phonon distribution.