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Quantum dots (QDs) formed on GaAs(100) substrates by InAs deposition followed by (Al,Ga)As or (In,Ga,Al)As overgrowth demonstrate a photoluminescence (PL) peak that is redshifted (up to 1.3 μm) compared to PL emission of GaAs-covered QDs. The result is attributed to redistribution of InAs molecules in the system in favor of the QDs, stimulated by Al atoms in the cap layer. The deposition of a 1 nm thick AlAs cover layer on top of the InAs-GaAs QDs results in replacement of InAs molecules of the wetting layer by AlAs molecules, leading to a significant increase in the heights of the InAs QDs, as follows from transmission electron microscopy. This effect is directly confirmed by transmission electron microscopy indicating a transition to a Volmer-Weber-like QD arrangement. We demonstrate an injection laser based on this kind of QDs. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Reports on the results of photoluminescence analysis of ion-implanted and flash-annealed cadmium tellurium. Overview of the annealing of implantation-induced damage in crystals; Comparison between flash and furnace annealing; Example of the problem of separating growth and annealing-induced spectral characteristics from those due to dopant activation.

Describes the band-to-band luminescence of ion-implanted indium phosphide after rapid lamp annealing. Technique for obtaining important information on the rapid lamp annealing of ion-implanted semiconductors; Features of such technique; Defects produced by ion implantation at low or elevated temperatures.

Focuses on a study on the variation of the reflectivity and stopband width of disordered gallium arsenide distributed Bragg reflectors (DBR) using thermal annealing of semiconductor DBR. Introduction to vertical cavity optoelectronic devices such as lasers and modulators; Derivation of equation; Experimental setup; Results.

Presents a study that calculated the gain-current coefficient and current density at transparency of gallium arsenide/aluminum-gallium arsenide and indium-gallium arsenide/gallium arsenide/aluminum-gallium arsenide quantum-well (QW) laser structures as a function of QW thickness by a straightforward numerical calculation. Optimum QW thicknesses; Use of the accepted semilogarithmic expression for threshold current density of QW lasers; Reduction of the laser threshold current density.

Presents a study that examined the effect of active cavity layer thickness variations on the operating characteristics of low voltage high performance asymmetric Fabry-Perot modulators. Information on the development of high performance surface-normal optical modulators; Schematic illustration of a generic asymmetric Fabry-Perot structure; Discussion on wavelength variations.

Presents a study which measured the silicon and iron depth distributions in silicon-implanted semi-insulating indium phosphide as a function of implant temperature and post-implants annealing technique. Applications of indium phosphide in optoelectronic and microwave devices; Investigation of the initial crystalline quality; Redistribution of iron following room temperature implant of silicon and annealing.

Focuses on a study which investigated the heterojunction of photodiodes using InAs/Ga[sub1-x]In[subx]Sb strained-layer superlattice. Heterostructure design; Experimental procedures and results; Discussion; Conclusions.

Presents information on a study that measured the increase in threshold currents due to lateral carrier diffusion in InGaAs/AlGaAs quantum-well (QW) ridge-waveguide laser diodes. Sample preparation and characterization; Optical gain calculation for the InGaAs QW; Conclusions.

Focuses on a study which examined the tunneling mechanism of electrons and holes to surface states from near-surface Al[sub0.3]Ga[sub0.7]As/GaAs quantum wells, using steady-state and time-resolved photoluminescence spectroscopy. Introduction to tunneling mechanism; Experimental procedure; Results and discussion.

Presents the results of luminescence studies for free-standing cadmium-zinc-sulfur/zinc-sulfur layer superlattices. Band discontinuity; Growth of the compounds by metal-organic vapor phase epitaxy; Photoluminescence characteristics.

Presents a study which investigated the phenomenon of layer disordering in cadmium zinc selenide/zinc selenide (ZnSe) and ZnSe/zinc sulfide strained layer superlattices by germanium diffusion. Fabrication of ZnSe-based optical waveguides; Significance of the development of laser processing techniques; Results of the study.

Presents a study that investigated the polarization dependencies in the low-temperature photoluminescence and photoluminescence excitation of GaAs/AlGaAs quantum wire arrays. Discussion on the features of polarization modulation using a photoelastic modulator; Experiment conducted; Results.

Analyzes the waveguide structures for quantum well lasers. Details on the graded-index profile in the waveguide lasers; Use of the matrix approach in calculations; Description of the waveguide structures.

Examines electric-field-induced absorption changes in triangular quantum wells grown by pulsed-beam molecular-beam-epitaxy technique. Overview of previous studies on square quantum wells; Types of triangular quantum wells; Details of experimental techniques used; Explanation for the quenching of tectonic absorption in triangular quantum wells.

Presents a study that developed a practical technology for self-aligned silicon-zinc diffusion into gallium arsenide and aluminum gallium arsenide. Details of the experiment; Results and discussion; Conclusions.