physica status solidi (b) · 1992 · 27 citations · 23 references
EngineeringMaterials EngineeringMaterials ScienceOptoelectronicsRecombinationSemiconductor MaterialsOptical Properties Of SemiconductorsSemiconductor Device MaterialsSemiconductor HeterostructuresSemiconductor PhysicsThermal Properties Of SemiconductorsWide Band Gap SemiconductorsAnisotropyExciton StatesLattice MismatchLattice Mismatch EffectsLocalized StatesPhotoluminescencePhotoluminescence SpectroscopyValleys
Abstract An extensive study of time‐resolved photoluminescence is made in the temperature range 1.8 to 50 K on nine samples of type‐II GaAsAlAs (001) superlattices. In previous publications, the region is identified where the states derived from X z valleys are lower than those derived from X xy valleys, in agreement with a simple model involving the competition between X‐type valley anisotropy and X valleys splitting caused by the small lattice mismatch between AlAs and GaAs. An analysis is given of the luminescence processes and of their evolution with temperature, as a function of AlAs and GaAs layer thicknesses. Excitons localized by interface roughness are found to decay through radiative processes at low temperature. A model of thermal excitation from the tail of localized exciton states is introduced, which helps to identify the pertinent parameters of temperature behaviour in these samples.
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Linewidth dependence of radiative exciton lifetimes in quantum wells
Jochen Feldmann, G. Peter, E. O. Göbel et al. · Physical Review Letters · 1987 · 1.1K citations