Effect of well width variation on type-I/type-II photoluminescence in GaAs/AlAs single quantum wells

✍ Scribed by L.J. Blue; T. Daniels-Race; C.N. Yeh; L.E. McNeil

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 197 KB
• Volume: 21
• Category: Article
• ISSN: 0749-6036
• DOI: 10.1006/spmi.1995.0162

✦ Synopsis

We have investigated type-I/type-II transitions in MBE-grown 20, 35, and 50 A ˚GaAs/AlAs single quantum wells using photoluminescence (PL) spectroscopy. The 20 and 50 A ˚wells show a type-I peak, while the 35 A ˚well has PL peaks corresponding to both type-I and type-II transitions. Peak assignment for the 35 A ˚-well sample is based upon excitation intensity dependent measurements, and the strength of the type-II transition in this sample is attributed to -X mixing. Superperiodicity has been put forth as a possible explanation for -X mixing effects in superlattice structures, but the observation of this phenomenon in a single quantum well structure suggests that superperiodicity is not required for -X mixing to occur.