High-quality strain-induced quantum dots with properties that can be tailored have been fabricated by growing small InP islands on top of an InGaAs/GaAs near-surface quantum well. The quantum dots show small inhomogeneous broadening, and peaks from the ground and excited state transitions are well resolved in the photoluminescence spectra measured from the dots. The depth of the confining potential and the energy level separation can be varied over a relatively wide range from 35 meV to 100 meV and from 7 meV to 25 meV, respectively, by changing the top barrier thickness of the near-surface quantum well and/or the size of the stressor islands.
Ahopelto, J., Sopanen, M., & Lipsanen, H. (1999). Tailoring of energy levels in strain-induced quantum dots. Japanese Journal of Applied Physics, 38(1), 1081-1084. https://doi.org/10.1143/JJAP.38.1081