Bunched photon statistics of the spectrally diffusive photoluminescence of single self-assembled GaAs quantum dots

Spectral diffusion in the optical transition of self-assembled GaAs quantum dots is studied using the intensity correlation functions of spectrally filtered photoluminescence signals. Analysis of the bunched photon correlation reveals the statistical nature of frequency drift over six orders of magnitude in time (10−9–10−3 s) with 10 μeV energy resolution.We demonstrate large variation in the characteristic time of spectral diffusion reflecting carrier hopping among limited numbers of trapping sites in the vicinity of a quantum dot.