Skip to Main Content
Your organization might have access to this article on the publisher's site. To check, click on this link:http://dx.doi.org/+10.1063/1.4803683
Photo darkening was observed in epitaxial InGaAs/GaAs quantum dots (QDs). The photoluminescence (PL) intensity of the QDs showed a non-reversible decrease under continuous laser irradiation. The time constants varied from tens of minutes to several hours, depending on the applied laser power. Based on the spectral evolution, it was concluded that the observed phenomenon should originate from laser induced structural damage and a sustained increase of non-radiative recombination rate in the wetting layer. Additionally, according to the PL decay dynamics at different laser powers, it is argued that there should exist other processes that hinder PL degradation at a high laser power.