CARRIER CAPTURE PROCESSES IN GAAS-ALGAAS QUANTUM-WELLS DUE TO EMISSION OF CONFINED PHONONS

Carrier capture times are calculated for GaAs-AlxGa1-xAs multiple quan tum wells due to the emission of confined longitudinal optical phonons via electron-phonon (Frohlich) interaction. We compare our results wi th several capture times measured by optical techniques and we discuss the importance of a knowledge of the carrier excitation details in or der to obtain an appropriate interpretation of the experimental result s. We show that electrons excited into confined states with a large ki netic energy (which have been ignored in previous works) strongly infl uence the overall capture times.