Strain profile, electronic band structure and optical gain of self-assembled Ge quantum dots on SiGe virtual substrate

In this paper, we study one such possible structure - self assembled Ge QDs embedded on Si_0.5Ge_0.5 virtual substrate with the same capping layer. A wetting layer is considered to simulate the actual scenario. Then we conduct a theoretical study on the strain and electronic band structure of this model. We employ the valence force field (VFF) method using Keating potential to estimate the strain followed by 8 band k·p method to calculate the electronic band structure taking the Γ valley into consideration. Finally we study the optical gain of the system for varying carrier concentrations.