Room-temperature blue-green emission from InGaN/GaN quantum dots made by strain-induced islanding growth

InGaN/GaN self-assembled quantum dots (QDs) were obtained by molecular beam epitaxy making use of the Stranski–Krastanov growth mode. Room-temperature photoluminescence (PL) energy of QDs was observed from 2.6 to 3.1 eV depending on the dot size. PL linewidths as low as 40–70 meV at 10 K and 90–110 meV at 300 K indicate low dot size dispersion. The comparison of PL intensity versus temperature of an InGaN epilayer and InGaN/GaN QDs demonstrates the higher radiative efficiency of the latter.