Spherical quantum dot with added parabolic confinement as a nanoscale tunable radiation detector

Stark effect of interactive electron–hole pairs in spherical semiconductor quantum dots

“…Since our aim is to understand the semiconductor optical bands blue-shift as a main effect, we shall discard spin effects (electron-hole spin coupling or external applied magnetic field) and consider non-relativistic spinless electron or hole, trapped in a confining infinite spherical potential well. There exist other models with parabolic confinement [3,16] or parabolic potential superimposed to an infinite potential well [17], which are used to explain certain spectroscopic data; but the concept of a QD size is then not so well defined. Here, we adopt the EMA model previously introduced.…”

“…There exists other models with parabolic confinement [53,54] or parabolic potential superimposed to an infinite potential well [55], but the concept of a QD size is then not so well defined. As Stark effect in semiconducting microcrystallites manifests itself through an energy shift of the electron-hole total energy levels, we have to deal mainly with energy eigenvalue differences of a Hamiltonian.…”

“…In order to apprehend correctly the origin of these quantum size effects, a first theoretical attempt to describe electronic properties dependent semiconductor QDs has been elaborated upon a particle-in-a-sphere model in the effective-mass approximation (EMA) [12,13,14], in which both electron and hole behave as non-interacting electrons and holes, trapped in a spherical infinite potential well but with different masses. Since 1973, the QD spherical shape has been used [15] and continues to be very popular over the years [2,12,14,16,17]. Because of the usual assumption of parabolic band structure, their effective mass is commonly defined through the inverse of the second derivative of their kinetic energy with respect to their momentum.…”

Lamb shift of interactive electron-hole pairs in spherical semiconductor Quantum Dots

“…Such model leads to an overestimation of the electron-hole pair ground state energy for small QDs, which can be corrected by restoring a confining finite potential step of experimentally acceptable height [36]. Other QD models with parabolic confinement [37,38] or parabolic potential superimposed to an infinite potential well [39] exist. But, the concept of QD size is no longer well-defined since their eigenfunctions are delocalized.…”

Photoionization cross section and refractive-index change of hydrogenic impurities in a CdS-SiO2 spherical quantum dot

“…Because of their reduced dimensionality, these nano-scaled structures show very unique properties for device applications, especially in laser and optoelectronic technology [1][2][3][4][5][6][7][8][9][10][11][12]. Therefore, great attention has been focused on the electronic and op-tical properties of these confined systems.…”