In/Ga inter-diffusion in InAs quantum dot in InGaAs/GaAs asymmetric quantum well

J Nanosci Nanotechnol. 2012 Jul;12(7):5774-7. doi: 10.1166/jnn.2012.6280.

Abstract

The Photoluminescence spectra (PL), their temperature and power dependence were investigated for the ground state in InAs quantum dots (QDs) embedded in InGaAs asymmetric quantum well (Asym. QW). In-atom segregation is well known phenomena in such structures, which result in altering the inter-atomic distances; as a consequence the thermo-dynamical parameters change as well, namely Debye temperature. The bigger value of Debye temperature for the studied sample with respect to the corresponding bulk value is attributed to In/Ga inter-diffusion during growth. The inter-diffusion process causes non-radiative defects in the sample. As a consequence, rapid decrease in the QDs integrated emission intensity as the temperature increases was occurred.