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The accuracy of different transfer matrix approaches, which are used for solving the stationary effective mass Schrodinger equation for arbitrary one-dimensional potentials, is examined. Analytical model potentials as well as self-consistent Schrodinger-Poisson simulations of a heterostructure device have shown that a symmetrized transfer matrix approach has produced a similar accuracy as the Airy function method at a reduced numerical cost, thus avoiding the numerical problems associated with Airy function.

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.

Commercially available quantum-well infrared focal plane array (FPA) is compared with a custom quantum-dot (QD)-in-a-well (DWELL) infrared FPA in the long-wave infrared (LWIR). The quantum-well FPA has displayed a higher collection efficiency of 1.3 when compared to the DWELL.

A continuously tunable semiconductor disk laser with intracavity second-harmonic generation (SHG) is evaluated using a wedged and antireflection-coated diamond heatspreader. Findings reveal output powers of more than 600 mW tunable over 10 nm around 530 nm.

(Received 25 June 2005; accepted 21 October 2005) We investigate the problem of a quantum particle in a one-dimensional finite square well. In the standard approach the allowed energies are determined implicitly as the solutions to a transcendental equation. We obtain the spectrum analytically as the solution to a pair of parametric equations and algebraically using a remarkably accurate approximation to the cosine function. The approach is also applied to a variety of other quantum wells.

The growth and characterization of quantum dot-quantum well nanostructures with photoluminescence (PL) that is tunable over the visible range is described. The contrasting aspects of the internal structure are discussed in terms of the various reactivities and are vital for understanding the optical properties of such complex heterostructured nanomaterials.