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A series of high-mobility [Al.sub.0.12][In.sub.0.88]Sb/InSb heterostructures are grown by molecular beam epitaxy to examine the fabrication of micro-Hall magnetic field sensors. The results have shown that the utility of devices with larger devices has led to magnetic field detection in the pT range at low temperatures and sub-nT range even at room temperature.

An alternative guided-wave optical interconnection architecture, based on using prismatic coupling elements, is described for enabling high-efficiency coupling into and out of an underlying multiple-quantum-well (MQW) modulator. The ray-trace and finite-difference time-domain simulation results have shown high coupling efficiency of the prism coupling structure.

A charge control model is developed for the transient analysis of the bipolar transistor laser in forward active mode in order to describe the dynamics of electron, photon and charge densities. The analysis of laser switching has shown that the turn-on time is reduced by increasing the base current or decreasing the spontaneous emission lifetime of electrons in the quantum well.

A method based on finite-difference mode convergence technique is described for analyzing nonlinear multilayered-planar waveguides and multiple-quantum-well structures. Many waveguide structures are analyzed in order to test the accuracy and establish the efficacy of the algorithm as a useful analysis recipe for modeling and understanding the modal properties of nonlinear multilayered waveguides.

The carrier transfer between quantum dot (QD) and quantum well (QW) layers is analyzed in a hybrid dot-well system based on InAs QDs and InGaAs QWs. Strong state-filling effects of the excited QD states have affected the carrier transfer efficiencies.

The article presents a complete analysis of the various nanostructured work function electrodes that are formed from a metal layer and a base substrate. The application of these electrodes for different thermionic and thermotunnel devices is also discussed.

An epitaxied AlGaAs/GaAs/AlGaAs heterostructure is analyzed by using the low frequency noise technique over a wide range of temperature as function of bias. Thermal activation energies and capture cross sections of traps responsible for the generation-recombination noise are extracted from an Arrhenius plot.

The linear and nonlinear optical response of intersubband transitions in a semiconductor quantum well is described. The coupling of the quantum well structure with the electromagnetic field is described by using the nonlinear density matrix equations, in the two-subband approximation.

Exciton localization in ZnO/[Mg.sub.x][Zn.sub.1-x]O quantum wells (QWs) is examined with various ZnO well widths for the fixed [Mg.sub.0.23][Zn.sub.0.77]O barrier height. The band characteristics and strong exciton localization in ZnO/[Mg.sub.0.23][Zn.sub.0.77]O QWs are attributed to the fluctuations associated with the inhomogeneous broadening.

The article discusses a newly developed Aharonov-Bohm (AB) system, which is completely based on the various electron-hole bilayer nanotubes made of rolled-up type-II band aligned quantum wells. These nanotubes are shown to be widely used for a large number of magneto-optical switching devices and similar applications.

Several nanotexturing InGaN/GaN multiple quantum wells are employed to explain the relaxation taking place in the lattice-mismatched strain by deep postetching. The various effects of the strain on the optical properties are also determined.

The effective-mass Hamiltonian model of semiconductors quantum well structures was utilized to study the electronic structures of the [Gamma]-conduction and L-conduction subbands of GeSn/GeSiSn strained quantum well structure with an arbitrary composition. The theoretical model indicated that the band structure could be widely modified to be type I, negative-gap or indirect-gap type II quantum well by changing the mole fraction of [alpha]-Sn and Si in the well and barrier layers, respectively.

Two types of devices with the same fabrication procedures except for the growth conditions for the InGaN quantum wells (QWs) were examined to study the degradation of GaN-based light-emitting diodes due to high dc current stress. The data show that an increase in the growth rate in the InGaN layer led to the domination by the step flow growth mode over the spiral growth mode in the MQWs.

The emission intensity of GaInN quantum well structures with varied electron and hole wave function overlap were analyzed by temperature and excitation power dependant and time-resolved photoluminescence to determine the parameters which affect the internal quantum efficiency of GaInN quantum well structures. The temperature dependent photoluminescence emission intensity for thick polar quantum wells could be partially assigned to increased screening effects and higher quantum well barriers for thicker quantum wells.

The tunneling current induced by a terahertz (THz) field applied to an asymmetric double quantum well is examined, where the excitation is coupled to a nearby continuum of extended states. The induced current is determined as a function of the intensity of the THz field and a second THz field is used to produce nonlinear processes that are useful for controlling the interference effects.

The magnetotransport properties of a gated [In.sub.0.53][Ga.sub.0.47]As/InP quantum well structure are studied in the presence of spin splitting when only one electronic subband is occupied. The studies have shown that larger quantum mobility is found for the higher-energy spin subband and the difference between the quantum mobilities for the two spin subbands is altered with the gate.

The properties of ionized-donor-bound excitons in a parabolic quantum-well wire in the presence of a magnetic field are analyzed in the framework of effective-mass envelope function theory. The results have shown that the binding energy has increased as the oscillator length has decreased and that it is also enhanced by increasing the magnetic field.

The temperature-dependent surface photovoltage spectroscopy (SPS) technique is employed to explain the characterization of the highly strained InGaAs/GaAs double quantum well (DQW) structures. The band lineup and several other properties of the structures are also analyzed.

The article uses electron temperature model to study the energy loss rate of hot electrons in a semiconducting freestanding quantum well structure, in the presence of zero and finite quantizing magnetic field. Findings are evaluated to those obtained for bulk description of acoustic phonon modes.

The optical characteristics of a nonpolar a-plane InGaN/GaN quantum well with different indium compositions, quantum well widths and injection carrier densities are discussed. The optimization condition is studied for designing the a-plane InGaN quantum well light emitting diode (LED) for applications, such as liquid crystal display backlight modules and lasers.

An ensemble of Monte Carlo simulations are applied to study the high-field transport properties of a bilayer two-dimensional electron gas in a wide quantum well (QW) subjected to an in-plane magnetic field. The magnetic-field-dependent behavior of drift velocity is qualitatively explained as the competition between the magnetic-field-induced depopulation of the antibonding subband and the electron effective mass enhancement.

The fabrication of a high-luminance white-light organic light-emitting diode (OLED) with dual-emission layers (EMLs) and their potential application in displays, backlight units, and general lighting is described. The luminance and the emission color of the device is enhanced by using the 2,9-dimethyl-4,7-diphenyl-1,10-phenanhroline hole blocking layers (HBLs).

The effect of polarization induced electric fields on the wavelength and the refractive index of intersubband transitions (ISBTs) in AlN/GaN coupled double quantum wells (CDQWs) is analyzed by solving Schrodinger and Poisson equations self-consistently. The results are used for discussing the prospects of nitride QWs for electric-optical modulation via cross-phase modulation operating within optical communication wavelength range.

A two-dimensional numerical simulation is employed to study the intrinsic mechanisms of drain lag and current collapse in GaN-based high-electron-mobility transistors. The results revealed that better electron localization that could reduce the current collapse is possible by considering quantum-well high-electron-mobility transistors.

A theoretical calculation of the effect of an electric field applied either parallel or perpendicular to the direction of confinement on the interband optical absorption of semiconducting nanostructures such as quantum wells, quantum wires, and quantum boxes are presented. The absorption of semiconducting nanostructures are found to be greater when the electric field is along the direction of carrier confinement than when it is perpendicular to the direction of carrier confinement.

Spatial nonlocal effects on optical absorption spectra from the terahertz optical interaction with semiconductor quantum wells (QWs) are examined for two types of polarized states. The studies have shown that the spatial nonlocality of optical responses can lead to not only the blueshift but also the redshift of optical spectral, which has depended on the QW depth.

A-plane [In.sub.x][Ga.sub.1-x]N/GaN multiple-quantum-wells (MQWs) samples are achieved by using r-plane sapphire substrates and optical quality is examined by using photoluminescence (PL) and time resolved PL measurements (TRPL). The results have shown that the indium content in a-plane InGaN/GaN MQWs has not only affected the optical performance, but is also important for application of nitride semiconductors.

High quality GaN/AlGaN multiquantum well (QW) structures are grown by ammonia molecular beam epitaxy along the (0001) polar and (1120) nonpolar directions. The quantum confinement has remained practically independent of the applied hydrostatic pressure and the built-in electric field has increased with pressure.

Enhanced side-mode suppression in Bunimovich stadium lasers with strained InGaAs/InGaP quantum well (QW) active regions is described. The improvement in side-mode suppression is a consequence of coherent beating between orbits leading to a Vernier effect.

The key low-temperature scattering mechanisms for holes in strained single-side modulation-doped SiGe/Ge/SiGe square quantum wells (QWs) are identified. The calculated hole mobility in Ge strained QWs has displayed a special channel-width dependence with a sharp peak.

AlGaN/AlN/GaN high electron mobility transistor heterostructures grown by metal-organic chemical vapor deposition are studied by temperature dependent time-resolved photoluminescence. The self-consistent calculation of the band potential profile has suggested a recombination mechanism for the AlGaN-related emission involving electrons confined in the triangular AlGaN quantum well and holes weakly localized due to potential fluctuations.

Selective area epitaxy is used to grow pyramidal GaN stripes followed by InGaN multiple quantum well (MQW) structures to produce long-wavelength green light emission. The redshifts obtained from the stripes due to enhanced delivery of indium species could find potential application to develop green and white light-emitting diodes and integrated photonic devices.

The analysis of chemical changes determined from the quantitative comparison of intensity distribution across an interface in high resolution transmission electronic microscopy (HRTEM) images is described. Four different samples of InGaP/GaAs quantum wells grown with different interfacial schemes are characterized.

The nanoscale InGaAs/InAlAs multi quantum well structures were used to analyze the nonparabolicity of the conduction band in [In.sub.0.53][Ga.sub.0.47]As. The results obtained from the method provide a direct means to determine the quantum well thickness.

The theoretical component of a combined experimental and theoretical investigation on electronic properties of InAs/GaSb-based quantum well systems is presented.

A comprehensive study of the growth and fabrication of Bragg-spaced quantum well, a type of resonant photonic band gap structure is conducted. Results revealed that drift in the growth rate greater than a few percent leads to collapse of the resonant photonic band gap (RPBG), while random disorder of several percent leads to extra peaks in the RPBG due to coupling to the intermediate band.

The vertical electron transport in semiconductor multiple-quantum-well structures within the sequential tunneling approaches and under assumption of resonant interwell transitions is analyzed. A transition between N- and Z-shaped curves is observed when the number of layers in the structure is varied and the structures with sharp transition resonances and low overall conductivity are in favor of the formation of Z-shaped portions of I-V curves.

The effects of the designated interfacial layers between the wells and barriers of IaGaN/GaN quantum-well (QW) samples on their optical and nanostructural properties are analyzed. The widely used QW structure shows the lowest photoluminescence (PL) and electroluminescence (EL) emission efficiencies, the smallest PL and EL emission photon energies and the generally longest PL decay times, suggesting that the quantum-confined Stark effect (QCSE) is the strongest in this sample.

The valley splitting in strained silicon quantum wells with a V-shaped potential is calculated variationally using two-band-binding model. The results revealed that silicon X-valley quantum wells display interesting behavior when subjected to a V-shaped potential.

An analysis on the effect of the strain field originating from a subsurface stressor on the electronic properties of nitride semiconductors is presented. The isotropic elasticity of utilized to determine the strain field in the structures under investigation.

The variations of the optical and electrical characteristics of a vertical cavity surface emitting laser based on GaAs quantum wells are monitored. The results allow deducing the equivalence between electron and proton irradiations.

The results of the effect of a transverse electric field on the ground and the first few excited states of the electrons confined in a quantum wire are used to examine the effects of the electric field o the intersubband optical absorption on such quantum wires. The findings state that for small wire radii and for strong electric fields, the infinite well model breaks down.