PHOTOINDUCED PHONON FLUORESCENCE IN GAAS ALXGA1-XAS QUANTUM-WELLS/

Phonon fluorescence in semiconductor quantum wells induced by two radi ation fields is investigated here. The rate of change of the interface LO-phonon population due to the scattering of confined electrons in t he two laser fields is calculated using first-order perturbation theor y from which the amplification coefficient is derived. It was found, b y considering the full photon absorption and emission processes of las er fields that for a semiconductor quantum well at arbitrary temperatu re, interface LO phonons propagating parallel to the direction of pola rization of the external fields may be amplified over a relatively bro ad band of phonon wavenumber. An application is made for a GaAs/AlGaAs quantum well system. (C) 1998 Elsevier Science Ltd All rights reserve d.