[16a-2E-1~9] 3.13 Semiconductor optical devices

▲ [16a-2E-3] Impact of surface charge on spectrally diffusive photoluminescence in GaAs quantum dots grown by droplet epitaxy

〇(P)Neul Ha¹, Takaaki Mano¹, Takashi Kuroda¹, Shun-Jen Cheng², Paul M. Koenraad³, Akihiro Ohtake¹, Yoshiki Sakuma¹, Kazuaki Sakoda¹ (1.NIMS, 2.NCTU-ROC, 3.TU Eindhoven)

Keywords:Line broadening,Quantum dots,Droplet epitaxy

Making use of droplet epitaxy, we systematically controlled the height of GaAs quantum dots by more than one order of magnitude. The photoluminescnece spectra of single quantum dots revealed the strong dependnece of the spectral linewidth on the dot height. The measured height dependent of the linewidths is in good agreement with Stark coefficients calculated for experimental shape variation. We attribute the microscopic source of fluctuating electric fields to random motion of surface charges at the vacuum-semiconductor interface.