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Within the framework of adiabatic approximation, the energy levels and direct interband light absorption in a strongly prolated ellipsoidal quantum dot are studied. Analytical expressions for the particle energy spectrum and absorption threshold frequencies in three regimes of quantization are obtained. Selection rules for quantum transitions are revealed. Absorption edge and absorption coefficient for three regimes of size quantization (SQ) are also considered. To facilitate the comparison of obtained results with the probable experimental data, size dispersion distribution of growing quantum dots by the small semiaxe in the regimes of strong and weak SQ by two experimentally realizing distribution functions have been taken into account. Distribution functions of Lifshits–Slezov and Gaussian have been considered. [ABSTRACT FROM AUTHOR]

Interband transitions in a narrow-gap InSb cylindrical quantum dot (QD) have been theoretically studied in the regime of strong dimensional quantization with allowance for a nonparabolic dispersion of electrons and light holes. The corresponding absorption coefficients and threshold frequencies for a QD array are calculated within the framework of a two-band Kane model for electrons and light holes and a parabolic dispersion law for heavy holes. These threshold frequencies fall in the IR range. Quantitative calculations are performed using the recent data of Moiseev et al. [1] on the growth of InSb quantum dots by liquid phase epitaxy. [ABSTRACT FROM AUTHOR]

The influence of hidden symmetry on two-dimensional excitonic states in semiconductor quantum wells is investigated. It is shown that excitonic states in quantum wells, with the parabolic dispersion law for the electron and hole, and Sommerfeld's coefficients for excitonic transitions are determined only with the principle quantum number within the framework of two-dimensional Coulomb potential. This is a result of hidden symmetry of two-dimensional Coulomb problem, conditioned by the existence of two-dimensional analog of the Runge-Lentz vector. For the narrow gap semiconductor quantum well with the non-parabolic dispersion law of electron and hole, in the two-band Kane model, it is shown that two-dimensional excitonic states are described in the frames of analog of the Klein-Gordon equation with the two-dimensional Coulomb potential. Non-stability of the ground state of the two-dimensional Kane's exciton investigated. [ABSTRACT FROM AUTHOR]