Ordering of quantum dot molecules by self-organization

Lateral InAs quantum dot (QD) molecules are created by self-organized anisotropic strain engineering of a (In,Ga)As/GaAs superlattice (SL) template on GaAs (3 1 1)B by molecular beam epitaxy. During stacking the SL template self-organizes into a two-dimensionally ordered strain-modulated network on a mesoscopic length scale. InAs QDs preferentially grow on the nodes of the network due to local strain recognition. The QDs form a lattice of separated groups of closely spaced ordered QDs, whose number is controlled by the upper GaAs separation layer thickness on the SL template and the SL growth temperature. The QD molecules exhibit strong photoluminescence emission up to room temperature.