Long wavelength vertically stacked InAs/GaAs(001) quantum dots with a bimodal size distribution: Optical properties and electronic coupling

Investigation of strain in self-assembled multilayer InAs/GaAs quantum dot heterostructures

“…Then the substrate temperature was gradually reduced down to 520 1C with the growth of 1000Å intrinsic GaAs. This was followed by the growth of InAs QDs at a [17,18]. The dots are then overgrown with a combination capping of quaternary In 0.21 Al 0.21 Ga 0.58 As layer and GaAs layer at 520 1C.…”

Optical properties of stacked InAs self-organized quantum dots on InP (311)B

“…There have been several reports on the carrier dynamics of thermally activated carriers that migrate or tunnel from smaller sized QDs to larger dots via wetting layer. Such carrier dynamics is commonly observed in bimodal QD structures and is known to show a minimum PL linewidth at an intermediate temperature range [17], and exhibit two components following the Varshni law [18]. Here we further believe that the carriers can be transferred between QDs more easily in our stacked structure since carrier scattering would be reduced in an ideal three-dimensional superlattice structure.…”

Optical properties of multi-stacked InAs/GaNAs strain-compensated quantum dots

“…There have been several reports on the carrier dynamics of thermally activated carriers that migrate or tunnel from the smaller-sized QDs into larger QDs via wetting layers. Such carrier dynamics is known to cause a minimum PL linewidth at an intermediate temperature range [21], as well as the existence of two components of the Varshni law [22]. Here, we also believe that the carriers are transferred between QDs more efficiently in our stacked structures instead of other relaxation mechanisms such as non-radiative recombination, since the STEM images show no structural defects and dislocations in the stacked QD structures as from Fig.…”