Photoreflectance investigation of InAs quantum dashes embedded in In0.53Ga0.47As/In0.53Ga0.23Al0.24As quantum well grown on InP substrate

Photoreflectance (PR) measurements were performed on molecular-beam-epitaxy-grown self-assembled InAs quantum dashes (QDashes) embedded in an In0.53Ga0.47As/In0.53Ga0.23Al0.24As quantum well grown on InP substrate. PR resonances related to optical transitions in all relevant parts of the structure, i.e., InAs/In0.53Ga0.47As QDashes, InAs/In0.53Ga0.47As/In0.53Ga0.23Al0.24As quantum well, and in In0.53Ga0.23Al0.24As barriers were observed. By matching the theoretical calculations performed within the effective mass approximation with experimental data, the energy level structure of the whole system was determined. On the basis of the obtained energy level diagram, it was concluded that both electrons and heavy holes are localized within the InAs/In0.53Ga0.47As QDashes, the structure is of Type I. (c) 2006 American Institute of Physics.