Effect of conduction band non-parabolicity on the donor states in GaAs–(Al,Ga)As spherical quantum dots

The binding energy of a shallow, hydrogenic on-centre impurity in a GaAs–AlxGa1−xAs quantum dot is calculated using the standard variational technique. The effect of band non-parabolicity is considered using the Luttinger–Kohn ‘effective mass’ equation. The electronic energy level and the donor binding energy are computed as a function of the dot size, both in the presence and in absence of the band non-parabolicity effect. Results indicate noticeable differences in two cases, especially for small dots.