Binding energy of an off-center hydrogenic donor in a spherical quantum dot with strong parabolic confinement

In this paper, off-center impurity effects in a spherical quantum dot are theoretically studied by degenerate perturbation method in strong confinement. The binding energies are computed for the typical GaAs material as a function of the donor position. The numerical results show the quantum size effect. We note that crosses will not come forth any more, but gaps will appear between degenerate states in comparison with the results gained by using the method as in Bose [Physica E 4 (1999) 180].