A study of nitrogen incorporation in pyramidal site-controlled quantum dots.
We present the results of a study of nitrogen incorporation in metalorganic-vapour-phase epitaxy-grown site-controlled quantum dots (QDs). We report for the first time on a significant incorporation (approximately 0.3%), producing a noteworthy red shift (at least 50 meV) in some of our samples. Depending on the level of nitrogen incorporation/exposure, strong modifications of the optical features are found (variable distribution of the emission homogeneity, fine-structure splitting, few-particle effects). We discuss our results, especially in relation to a specific reproducible sample which has noticeable features: the usual pattern of the excitonic transitions is altered and the fine-structure splitting is suppressed to vanishing values. Distinctively, nitrogen incorporation can be achieved without detriment to the optical quality, as confirmed by narrow linewidths and photon correlation spectroscopy.
Tyndall National Institute, University College Cork, Lee Maltings, Cork, Ireland. gediminas.juska@tyndall.ie.
Gediminas
G
Juska
Valeria
V
Dimastrodonato
Lorenzo O
LO
Mereni
Agnieszka
A
Gocalinska
Emanuele
E
Pelucchi