We propose a new approximation scheme to obtain analytic expressions for the bound state energies and eigenfunctions of Yukawa like potentials. The predicted energies are in excellent agreement with the accurate numerical values reported in the literature.

Low-lying energy levels of two interacting electrons confined in a two-dimensional parabolic quantum dot in the presence of an external magnetic field have been revised within the frame of a novel model. The present formalism, which gives closed algebraic solutions for the specific values of magnetic field and spatial confinement length, enables us to see explicitly individual effects of the electron correlation.

We present a comparison of the band alignment of the Ga 1-x In x N y As 1-y active layers on GaAs and InP substrates in the case of conventionally strained and strained-compensated quantum wells. Our calculated results present that the band alignment of the tensiley strained Ga 1-x In x N y As 1-y quantum wells on InP substrates is better than than that of the compressively strained Ga 1-x In x N y As 1-y quantum wells on GaAs substrates and both substrates provide deeper conduction wells. Therefore, tensiley strained Ga 1-x In x N y As 1-y quantum wells with In concentrations of x≤0.53 on InP substrates can be used safely from the band alignment point of view when TM polarisation is required. Our calculated results also confirm that strain compensation can be used to balance the strain in the well material and it improve especially the band alignment of dilute nitride Ga 1-x In x N y As 1-y active layers on GaAs substrates. Our calculations enlighten the intrinsic superiority of N-based lasers and offer the conventionally strained and strain-compensated Ga 1-x In x N y As 1-y laser system on GaAs and InP substrates as ideal candidates for high temperature operation.

The focus of this paper is to present the calculations of the band alignment of indium-rich (>53%) highly strained Ga 1−x In x N y As 1−y quantum wells on InP substrates which allows an emission wavelength of the order of 2.3 µm. We concentrate on the band alignment of Ga 0.22 In 0.78 N 0.01 As 0.99 wells lattice matched to In 0.52 Al 0.48 As barriers. Our calculations show that the incorporation of nitrogen into Ga 1−x In x As improves the band alignment significantly allowing Ga 0.22 In 0.78 N 0.01 As 0.99 /In 0.52 Al 0.48 As quantum wells on InP substrates to compete with the unique band alignment of GaInNAs/GaAs quantum wells on GaAs substrates.

Both carrier and optical mode confinements are the basic ingredients while designing the semiconductor quantum well lasers. The former strongly depends on the band offsets of the heterostructure and the latter is mainly associated with the difference in the refractive index between the wave guiding core and the cladding layers. It is known that refractive index strongly depends on the direct band gap of the semiconductor material and the band gap of the III-N-V semiconductor layer can be engineered by means of adding nitrogen into InGaAs. We investigate, in this work, the refractive indices and the corresponding optical confinement factors of the proposed III-N-V laser material systems on GaAs and InP substrates.