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The effects of the Aluminium concentration on the emission of Al 0.45 In 0.55 As/Al y Ga 1− y As quantum dots (QDs) are investigated by photoluminescence (PL), with the excitation power density as a variable parameter. The influence of a varying barrier composition on the QD emission is investigated theoretically and discussed with respect to PL measurements. For the highest barrier composition value ( y = 0.77), we interpret the QD emission as originating from indirect type-II transitions involving electrons in the barrier X valley and heavy holes (HH), with S and P symmetry, in Al 0.45 In 0.55 As QDs. The PL spectra of the y = 0.38 sample exhibits three lines: two of them are related to indirect type-II transitions, in which the electron ground state belongs to the indirect gap (L and X) minima in the barrier conduction band, whereas the third transition is attributed to a direct type-I transitions.

We report photoluminescence (PL) characterization and model simulation of AlInAs/AlGaAs type-II quantum dots (QDs). A thorough and precise determination of the band parameters for QD and matrix materials is given, focusing on the effects of alloy composition and strain state on the electronic properties. Origins of experimentally observed PL emission peaks are identified through a comparison with the band lineup theoretically determined in this work. We interpret the QD emission as originating from indirect type-II transitions involving electrons in the barrier X valley and heavy holes with S and P symmetry.

Using third and fourth order perturbation theory inside a 14-band and 30-band k ⋅ p model, we have calculated the effective Lande factor g ∗ of Γ 6 C conduction electrons in GaAs and AlSb. A strong variation between both models is observed. We show that the 14-band formalism even in fourth order perturbation theory is not sufficient to predict an experimental data of g ∗ . However, results deduced by the 30-band k ⋅ p model are consistent with experimental data. In particular, the k ⋅ p Hamiltonian parameters are adjusted such that the g ∗ of GaAs and AlSb are respectively −0.391 and 0.81, in excellent agreement with the experimental values of −0.44 and 0.84.

We present a generalized theoretical description of the 30 × 30 k ⋅ p approach for determining the band structure of the direct-band-gap semiconductors (InAs, InP, InSb), including the d far-levels contribution. For all materials investigated, the resulting electronic band structure parameters are in good agreement with experimental values. This model gives access to the second conduction band which is useful for transport modelling. We finally show that this method also gives explicit expressions for the Luttinger parameters, the κ valence band parameter and the effective masses in the Γ valley.

A quantitative comparison of different k · p calculations of valence-band states in quantum-confined semiconductor heterostructures is presented. The importance of using the appropriate Hamiltonian form is studied quantitatively following a numerical method which enables discrimination between existing Hamiltonians. The correct form of the Hamiltonian appears to be the Foreman Hamiltonian, which gives physically reasonable results contrary to the symmetrized Hamiltonian.

A 40-band k⋅p model is used to compute the standard k⋅p band parameters at Γ, X, and L valleys in direct-band-gap bulk materials for Td group semiconductors. The values of the effective masses for electrons, heavy holes, and light holes in the Γ, X, and L valleys are in good agreement with those reported in other publications. Satisfactory agreement with available experimental data is also obtained by the present model. Finally, our results show that the effective Lande factor g∗, the κ valence band parameter, and the Dresselhauss spin-orbit coupling constant δ conicide well with available experimental data. The k⋅p Hamiltonian parameters, in particular, are adjusted to get g∗(GaAs)=−0.42, which turn out to be in agreement with the experimental value of −0.44.

The band structure of direct-band gap semiconductors (GaAs, InAs, InP) is described theoretically by using a 34×34 k⋅p model. We extend the sp3d5 basis functions by the inclusion of sV∗ orbitals. We find that the sp3d5s∗ k⋅p model is sufficient to describe the electronic structure of all materials investigated over a wide energy range, obviating the use of any d valence orbitals. Finally, our results show that Luttinger parameters, the κ valence band parameter, the effective Lande factor g∗, and the effective-masses in the X and L valleys are in good agreement with available experimental data. In particular, the adjustment of the k⋅p Hamiltonian parameters proved that g∗ of GaAs, InAs, and InP are, respectively, −0.41, −15.82, and 1.35, which are in good agreement with the experimental values of −0.44, −14.90, and 1.26.

A 34-band k ⋅ p model is used to compute the standard k ⋅ p band parameters at Γ, X and L valleys in indirect-band-gap bulk materials for Td (AlAs) and Oh (Si, Ge) group semiconductors. The values of the effective masses for electrons, heavy and light holes in the Γ, X and L valleys are in very good agreement with those reported in other publications. Satisfactory agreement with available experimental data is also obtained by the present model. Finally, our results show that the Luttinger parameters, the κ valence band parameter and the effective Lande factor g* are in good agreement with available experimental data. In particular, the adjustment of the k ⋅ p Hamiltonian parameters proved that the g* of AlAs, Ge and Si are respectively 1.50, −2.79 and 1.96, which are in good agreement with the experimental values of 1.52, −2.50 and 1.99.