Observation of sharp photoluminescence lines from self-assembled InGaN quantum dots

Summary form only given. Growth of GaN-based self-assembled quantum dots (QDs) has received great attention for application to blue light emitting lasers. Lasing action from a photo-excited InGaN QD laser at room temperature was recently reported. To confirm the effect of quantum-mechanically localized states in the QDs, discrete energy levels should be evidenced. However, there has been no report on sharp luminescence lines from GaN-based QDs. We investigate photoluminescence from MOCVD-grown InGaN QDs using micro-PL (/spl mu/-PL) through apertures in a metal mask on the QD sample. Very narrow spectral peaks with the line width of 170 /spl mu/eV were successfully observed. The linewidth is limited by the spectral resolution of the measurement system. This result clearly demonstrates localized excitonic states in the InGaN QDs.