Progress in Growth and Physics of Nitride-Based Quantum Dots

Abstract

Our recent progress in growth and optical properties of GaN-based quantum dot (QD) structures is reviewed. After discussing the impact of GaN-based QDs on threshold current characteristics, we have shown InGaN self-assembled QDs on a GaN epitaxial layer with average diameter as small as 8.4 nm and strong photoluminescence emission from the QDs at room temperature. Furthermore, light emission from individual QDs with sharp luminescence line was detected by single dot spectroscopy. Using these growth results, we fabricated a laser structure with InGaN QDs embedded in the active layer. A clear threshold was observed in the dependence of the emission intensity on the excitation energy at room temperature under optical excitation. Finally, growth of InGaN QDs grown by selective growth is also demonstrated.