Related papers: Quantum dot self-assembly driven by a surfactant-i…
We investigate island formation during heteroepitaxial growth using an atomistic model that incorporates deposition, activated diffusion and stress relaxation. For high misfit the system naturally evolves into a state characterized by a…
We studied and optimized the molecular beam epitaxy of GaSb layers on vicinal (001) Si substrates using a GaAs nucleation layer. An in-depth analysis of the different growth stages under optimized conditions revealed the formation of a high…
The investigation of small size embedded nanostructures, by a combination of complementary anomalous diffraction techniques, is reported. GaN Quantum Dots (QDs), grown by molecular beam epitaxy in a modified Stranski-Krastanow mode, are…
A number of recent experiments have showed that surfactants can modify the growth mode of an epitaxial film, suppressing islanding and promoting layer-by-layer growth. Here a set of coupled equations are introduced to describe the coupling…
We report a scalable molecular beam epitaxy strategy to achieve a low density of O-band electrically tunable InAs/InGaAs quantum dots (QDs) on GaAs(001) substrates. Our approach is based on a gradient deposition of InAs in the sub-ML regime…
Emerging applications of self-assembled semiconductor quantum dot (QD)-based nonclassical light sources emitting in the telecom C-band (1530 to 1565 nm) present challenges in terms of controlled synthesis of their low-density ensembles,…
We report on the epitaxial growth, theoretical modeling, and structural as well as optical investigation of multi-layer, site-controlled quantum dots fabricated using the buried stressor method. This advanced growth technique utilizes the…
Using three-dimensional k.p calculation including strain and piezoelectricity, we showed that the size of the quantum dot (QD) in the growth direction determines the influence of the (In,Ga)As capping layer on the optical properties of…
We report on a atomistic theory of electronic structure and optical properties of a single InAs quantum dot grown on InP patterned substrate. The spatial positioning of individual dots using InP nano-templates results in a quantum dot…
Site-controlled quantum dots formed during the deposition of (Al)GaAs layers by metalorganic vapor-phase epitaxy on GaAs(111)B substrates patterned with inverted pyramids result in geometric and compositional self-ordering along the…
The dynamic response of InAs/GaAs self-assembled quantum dots (QDs) to strain is studied experimentally by periodically modulating the QDs with a surface acoustic wave and measuring the QD fluorescence with photoluminescence and resonant…
We present a simulation to characterize the dependence on hydrostatic pressure for the photoluminescence spectra in self-assembled quantum dots with lens shape geometry. We have tested the physical effects of the band offset and…
This work studies the spontaneous self-assembly of Ge QDs on AlAs, GaAs, and AlGaAs by high temperature in-situ annealing in molecular beam epitaxy (MBE). The morphology of Ge dots formed on AlAs are observed by atom probe tomography, which…
The equilibrium shapes of InAs quantum dots (i.e., dislocation-free, strained islands with sizes >= 10,000 atoms) grown on a GaAs (001) substrate are studied using a hybrid approach which combines density functional theory (DFT)…
We report on a new approach for positioning of self-assembled InAs quantum dots on (110) GaAs with nanometer precision. By combining self-assembly of quantum dots with molecular beam epitaxy on in-situ cleaved surfaces (cleaved-edge…
The structural analysis of GaN and Al$_x$Ga$_{1-x}$N/GaN heterostructures grown by metalorganic vapor phase epitaxy in the presence of Mn reveals how Mn affects the growth process, and in particular the incorporation of Al, the morphology…
The model systems for self-organized quantum dots formed from elemental and compound semiconductors, namely Ge grown on Si(001) and InAs on GaAs(001), are comparatively studied by scanning tunneling microscopy. It is shown that in both…
Quasiparticle interference induced by cobalt adatoms on the surface of the topological insulator Bi$_{2}$Se$_{3}$ is studied by scanning tunneling microscopy, angle-resolved photoemission spectroscopy and X-ray magnetic circular dichroism.…
We demonstrate the Au-assisted growth of semiconductor nanowires on different engineered substrates. Two relevant cases are investigated: GaAs/AlGaAs heterostructures capped by a $50 {\rm nm}$-thick InAs layer grown by molecular beam…
We study the effect of insoluble surfactants on the wave dynamics of vertically-falling liquid films. We use three-dimensional numerical simulations and employ a hybrid interface-tracking/level-set method, taking into account Marangoni…