Quantum effects at the nanometric level have been observed in many confined
structures, and particularly in semiconductor quantum dots (QDs). In this work,
we propose a theoretical improvement of the so-called effective mass
approximation with the introduction of an effective pseudo-potential. This
advantageously allows analytic calculations to a large extent, and leads to a
better agreement with experimental data. We have obtained, as a function of the
QD radius, in precise domains of validity, the QD ground state energy, its
Stark and Lamb shifts. An observable Lamb shift is notably predicted for
judiciously chosen semiconductor and radius. Despite the intrinsic
non-degeneracy of the QD energy spectrum, we propose a Gedankenexperiment based
on the use of the Casimir effect to test its observability. Finally, the effect
of an electromagnetic cavity on semiconductor QDs is also considered, and its
Purcell factor evaluated. This last result raises the possibility of having a
QD-LASER emitting in the range of visible light
