2Egtransitions in GaSb-AlSb quantum-well structures

Abstract
Photoluminescence emission at twice the fundamental band-gap energy is observed in GaSb-AlSb multiple quantum-well structures for well thicknesses below 42 Å, whereas it is not observed for larger thicknesses. The intensity of the emission increases dramatically with decreasing well width below this value. The appearance of these novel features is traced to changes in the character of the band-edge wave functions due to quantum-well confinement.