For the numerical computing, we used k = 12.58, m* = 0.0665m0, ml = 0.30m0, where eg = 1.424 eV.

A schematic representation of a GaAs quantum dot doped with a homogeneous distribution of the donor impurities is shown in Figure 50. The edges for optical absorption from the first valence subband to the donor impurity band are represented by h co1, and to the first conduction subband by Eg. The transition hco2 corresponds to absorption to an impurity level associated with donors at the edges of the quantum dot. At the right we also show the density of the states for the impurity band.

In Figure 51, we display the donor binding energy as a function of the donor position inside the quantum dot for infinite potential well with different radii. The donor binding energy decreases as the donor position increases reaching a lG

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