Lateral ordering of quantum dots and wires in the (In,Ga)As/GaAs(100) multilayer structures

Abstract

The surface morphology and optical properties of the (In,Ga)As/GaAs(100) multilayer structures with self-organized quantum dots and quantum wires, which were grown by molecular-beam epitaxy, are investigated. It is found that the ordered arrangement of quantum dots in the heterointerface plane starts to form during the growth of the first periods of the multilayer structure. As the number of periods increases, quantum dots line up in series and form wires along the $$[0\bar 11]$$ direction. An increase in the lateral ordering of the structures under consideration correlates with an increase in the optical emission anisotropy governed by relaxation anisotropy of elastic strains and by the shape of nano-objects. A possible mechanism of lateral ordering of quantum dots and wires in multilayer structures, which includes both anisotropy effects of the strain fields and adatom diffusion, as well as the elastic interaction of neighboring quantum dots, is discussed.