In(x)Ga(1-x)As wurtzite nanoneedles are grown without catalysts on silicon substrates with x ranging from zero to 0.15 using low-temperature metalorganic chemical vapor deposition. The nanoneedles assume a 6 degrees - 9 degrees tapered shape, have sharp 2-5 nm tips, are 4 microm in length and 600 nm wide at the base. The micro-photoluminescence peaks exhibit redshifts corresponding to their inc...

We present a plane-wave ultrasoft pseudopotential implementation of first-principle molecular dynamics, which is well suited to model large molecular systems containing transition metal centers. We describe an efficient strategy for parallelization that includes special features to deal with the augmented charge in the contest of Vanderbilt's ultrasoft pseudopotentials. We also discuss a simple...

The structural analysis of GaN and Al x Ga1-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 of the surface, and the plastic relaxation of Al x Ga1-x N on GaN. Moreover, the doping with Mn promotes the formation of layered Al x Ga1-x N/GaN superlattice-lik...

Metalorganic chemical vapor deposition-grown In0.4Ga0.6As0.995N0.005 quantum well ~QW! lasers have been realized, at an emission wavelength of 1.295 mm, with threshold and transparency current densities as low as 211 A/cm ~for L52000 mm! and 75 A/cm, respectively. The utilization of a tensile-strained GaAs0.67P0.33 buffer layer and GaAs0.85P0.15 barrier layers allows a highly-compressively-stra...

We presented the results of electrical and optical studies of the properties of InxGa1−xN epitaxial layers (0.060 ≤ x ≤ 0.105) grown by metalorganic vapour phase epitaxy. Resistivity and Hall effect measurements of the samples were carried out at room temperature. Optical properties of the samples were characterized by photoluminescence and optical absorption spectroscopy. The comparison betwee...

The effect of an initial saturation coverage of antimony on the growth of indium arsenide quantum dots on gallium arsenide has been studied during metalorganic vapor-phase epitaxy. After depositing one to two bilayers of InAs at 723 K, the samples were quenched, transferred to ultrahigh vacuum, and characterized by scanning tunneling microscopy and x-ray photoelectron spectroscopy. It has been ...

Carbon doped AlInAs layers grown by low pressure metalorganic vapor phase epitaxy are investigated as a function of growth temperature. Photoluminescence spectra show a signi cant drop in peak intensity as the growth temperature is reduced, due to the incorporation of non-radiative defects. It is shown that the C doping is not related to the deterioration of the optical properties of the layers...

The metalorganic chemical vapor deposition of In0.06Ga0.94As1 xNx, with x 1⁄4 0.00–0.02, has been examined using nitrogen trifluoride (NF3) and tertiarybutylarsine. The solid N/V ratio increased linearly with the gas-phase N/V ratio up to a limit of 2.0% nitrogen in the film at a gas N/V 1⁄4 0.35. No further increase in nitrogen content could be achieved at a growth temperature of 550 1C unless...