Photoluminescence of arrays of vertically coupled, stressed InAs quantum dots in a GaAs(100) matrix

A study is made of the photoluminescence of arrays of vertically coupled, stressed InAs quantum dots created in situ by molecular beam epitaxy in a GaAs (100) matrix. The locations of the photoluminescence lines of the quantum dots and InAs wetting layer are studied as functions of the number of InAs deposition cycles and the average thickness of the GaAs spacer. The observed dependence is described in terms of a phenomenological model in which the shift in the photoluminescence band is assumed to be caused by a change in the ground state energy occurring as a result of a weak interaction among carriers localized in tunnel-coupled quantum dots. (C) 1996 American Institute of Physics.