Surface morphology and photoluminescence of InGaAs quantum rings grown by droplet epitaxy with varying In0.5Ga0.5 droplet amount

We have presented the study result of physical and optical properties of the InGaAs quantum ring (QR) structures grown by droplet epitaxy using molecular beam epixaty. The structural properties and quality of QRs strongly depended on In0.5Ga0.5 droplet amount. The photoluminescence (PL) results confirmed the crystal quality of the nanocrystal of the capped samples with the optimum In0.5Ga0.5 droplet amount. The optimum In0.5Ga0.5 amount is 3 and 4 ML (monolayer) under the droplet forming condition of 210 °C substrate and crystallization at 180 °C. The PL measuring parameters, including excitation intensity and polarization, have been varied. The polarized PL spectra indicated anisotropy in the QR structures.