  We report on the optical characterization of non-polar a-plane InGaN quantum
dots (QDs) grown by metal-organic vapor phase epitaxy using a short nitrogen
anneal treatment at the growth temperature. Spatial and spectral mapping of
sub-surface QDs have been achieved by cathodoluminescence at 8 K.
Microphotoluminescence studies of the QDs reveal resolution limited sharp peaks
with typical linewidth of 1 meV at 4.2 K. Time-resolved photoluminescence
studies suggest the excitons in these QDs have a typical lifetime of 538 ps,
much shorter than that of the c-plane QDs, which is strong evidence of the
significant suppression of the internal electric fields.
