Narrow spectral linewidth of single zinc-blende GaN/AlN self-assembled quantum dots

Abstract

We study by microphotoluminescence the optical properties of single self-assembled zinc-blende GaN/AlN quantum dots grown by plasma-assisted molecular beam epitaxy. As opposed to previous reports, the high quality of such zinc-blende GaN quantum dots allows us to evidence a weak acoustic phonon sideband as well as a limited spectral diffusion. As a result, we report on resolution-limited quantum dot linewidths as narrow as 500 ± 50 μeV. We finally confirm the fast radiative lifetime and high-temperature operation of such quantum dots.