We have investigated interdiffusion and surface segregation in molecular-beam-epitaxially-grown stacked self-assembled InAs/GaAs quantum dots. Using high-resolution cross-sectional scanning tunneling microscopy, we observe lateral variations in the vertical positions of In atoms in both the wetting layers and dot stacks. In some regions, the wetting layer thickness is much less than the dot hei...

Interdiffusion of In and Ga is observed in InGaN multiple-quantum-well superlattices for annealing temperatures of 1250 to 1400°C. Hydrostatic pressures of up to 15 kbar were applied during the annealing treatments to prevent decomposition of the InGaN and GaN. In as-grown material, x-ray diffraction spectra show InGaN superlattice peaks up to the fourth order. After annealing at 1400°C for 15 ...

We have studied the influence of SiO2 and TiO2 dielectric layers on the atomic intermixing of InxGa1−xAs/InP quantum well structures using the impurity-free vacancy disordering technique. Photoluminescence results revealed that an enhancement of interdiffusion was obtained when the samples were capped with SiO2. Although TiO2 layers were able to suppress the interdiffusion in the InGaAs/InP sys...

in this investigation, the mechanical properties of the blends of blown bitumen110/10, heavy vacuum slops (h.v.s), bitumen 60/70 penetration grade and isotactic polypropylene (ipp) were studied for the first time. our results showed that modulus varies non-linearly and at certain asphaltenes contents a peak appears. considering these phenomena it is revealed that in the absence of ipp, interact...