Photoluminescence studies of exciton recombination and dephasing in single InGaN quantum dots

This paper reports on time-integrated and time-resolved microphotoluminescence (μ-PL) measurements of single InGaN quantum dots (QDs). The linewidths of the μ-PL peaks originating from single metal-organic vapor phase epitaxy-grown III/V InGaN QDs are measured, implying dephasing times of at least 5 ps. Temporal fluctuations of the QD emission energy are observed, and these are explained in terms of randomly generated local electric fields inducing a Stark shift in the optical emission of the InGaN QDs. Time-resolved measurements demonstrate that decay dynamics from single InGaN QDs are exponential in nature. Measurements of the effect of temperature upon the recombination times in individual InGaN QDs have been performed from 4 to 60 K.