Articles you may be interested inGrowth by molecular beam epitaxy of self-assembled InAs quantum dots on InAlAs and InGaAs lattice-matched to InP High-temperature operation of self-assembled Ga In N As ∕ Ga As N quantum-dot lasers grown by solid-source molecular-beam epitaxy Self-assembled InAs quantum-dot ͑QD͒ molecules having high dot density and aligned dot set structure, which is defined by nanotemplates, were realized by thin capping and regrowth technique in a molecular-beam epitaxy process. Thin capping of GaAs on InAs QDs leads to the creation of nanoholes having a camel-like nanostructure due to anisotropic strain fields along the ͓110͔ crystallographic direction and anisotropic surface diffusion accompanying the QD collapse. Regrowth of InAs QDs on the nanohole templates initially results in the formation of QDs with good size uniformity in the middle of features with the shape of propeller blades. This takes place at the regrowth thickness of 0.6 monolayer ͑ML͒. The strain at propellers' edge starts to play its role, creating sets of quantum dots surrounding the initial and centered dots at the regrowth thickness of 1.2 ML. The elongated configuration of propellers' blades defines the pattern of QD sets having five to six dots on each side. The dot density of the QD molecules is 3 ϫ 10 10 cm −2 , one order of magnitude higher than that of initial dot density ͑2 ϫ 10 9 cm −2 ͒.

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