OPTICAL GAIN IN CDSE EPITAXIAL LAYERS ON GAAS

Stimulated emission and optical gain spectra are observed from wurtzit e-type CdSe/CdS/GaAs superstructures grown by hot wall epitaxy. The ga in originates predominantly from excitonic scattering processes with m aximum gain values of 175 cm-1 and with gain saturation starting at an excitation strip length of 200 mum. The gain is found to be much weak er when the CdSe is directly grown on GaAs substrates without CdS buff er layer.