Carrier trapping in single quantum wells with different confinement structures

Abstract

The trapping efficiency and trapping dynamics of photoexcited carriers in GaAs/AlGaAs single quantum wells with different confinement structures are examined at low temperature by means of picosecond luminescence as well as photoluminescence excitation spectroscopy. The trapping efficiency is 100% only in graded-index separate confinement heterostructures with a linear band-gap profile. The lower trapping efficiency of other confinement structures is due to radiative and nonradiative recombination in the confinement layers.