Improved luminescence efficiency of InAs quantum dots by nitrogen-induced strain compensation with GaNAs burying layers

摘要

Luminescence efficiency of InAs quantum dots (QDs) was shown to improve with strain compensation of the compressive strain in InAs QDs with tensile-strained GaNAs burying layers. The improved luminescence efficiency is discussed with the viewpoint of the average strain compensation in the strained semiconductor system. The red shift of the luminescence peak up to 1.55 /spl mu/m is also discussed from the same viewpoint of the strain compensation. The valence-force field model calculation of the strain field in the InAs QDs buried with the GaNAs strain compensating layer shows that the strain induced by nitrogen (N) atoms is significant and localized to respective N atoms and the more detailed information how the N atoms are incorporated during the burying process of the QDs with the GaNAs layers is necessary for the full description.