Exciton photoluminescence of quantum wells affected by thermal migration and inherent interface fluctuation

Exciton photoluminescence (PL) of quantum wells (QW), affected by the thermal migration and the inherent interface roughness, has been studied by a model which includes exciton transfer between the growth islands with one atomic layer difference in well thickness. Analytical expressions, showing a red shifting and linewidth changing compared to the exciton PL spectra without thermal migration, are obtained. At low temperature, the red shifting and the linewidth changing are uniquely determined by the geometry of the QW. At high temperature, the red shift and the linewidth changing depends on the temperature, structure, and inherent interface fluctuation of the QW. Under the influence of the thermal migration, the inconsistency of the PL and PL excitation spectra has been reexamined and quantitatively obtained as a function of the temperature, quality, and structure of the QW.