Carrier capture efficiency of AlGaAs/GaAs quantum wires affected by composition nonuniformity of an AlGaAs barrier layer

Abstract

Effects of composition nonuniformity of an AlGaAs barrier layer on the carrier capture efficiency of an AlGaAs/GaAs quantum wire (QWR) grown on nonplanar substrates are investigated using photoluminescence measurements. The photogenerated carriers first experience a redistribution from the high Al composition region to the low Al composition region in the AlGaAs barrier layer due to the potential difference caused by the composition nonuniformity before they are captured by quantum well or QWR regions. Such a carrier redistribution greatly affects the carrier capture efficiency of QWR structures.