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The high order self-organization of quantum dots is demonstrated in the growth of InAs on a GaAs(631)-oriented crystallographic plane. The unidimensional ordering of the quantum dots (QDs) strongly depends on the As flux beam equivalent pressure (P As ) and the cation/anion terminated surface, i.e., A-or B-type GaAs(631). The self-organization of QDs occurs for both surface types along ½ 113, while the QD shape and size distribution were found to be different for the self-assembly on the A-and B-type surfaces. In addition, the experiments showed that any misorientation from the (631) plane, which results from the buffer layer waviness, does not allow a high order of unidimensional arrangements of QDs. The optical properties were studied by photoluminescence spectroscopy, where good correspondence was obtained between the energy transitions and the size of the QDs.

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By taking advantage of the GaAs (631) corrugation self-assembled on top of multi-quantum well heterostructure interfaces, the modulation of the confined state wave functions (eigenstates) has been achieved, attaining quasi-one-dimensional or fractional dimension eigenstates. Two different theoretical approaches were used to compute the energy shift of subband optical transitions as a function of the interface corrugation geometrical configuration. For large nominal quantum well widths and small corrugation amplitude, the perturbation theory was employed, while a modified Lanczos algorithm assisted us to calculate the shifts when the corrugation amplitude was comparable to the nominal quantum well width. Experimentally, the heterostructures were grown by molecular beam epitaxy on (001) and (631) oriented substrates, where the quasi-one-dimensional ordering was reached by changing the As to Ga molecular beam fluxes ratio. It was found that the corrugated interfaces (i) break the wave function's in-plane symmetry, allowing transitions that, in principle, must be forbidden and (ii) induce blue shifts or red shifts in the order of 10 meV to the energy spectrum of the quantum wires depending on the lateral and vertical periodicities, exhibiting the presence of a lateral confinement system. The main result is the effective modulation of eigenstates through the interface corrugation control. Additionally, it was found that the interface modulation effect is greater for harmonic (n > 1) heavy (and light) hole subbands than for the ground states.