Oscillator strengths of the intersubband transitions in a semiconductor spherical quantum dot with the donor impurity in the center

Abstract

Oscillator strengths have been studied for a series of single-electron intersubband optical transitions nl → n′l′ (l ⩽ 4) in a spherical quantum dot (QD) with the donor impurity in the center (D0). Energy spectrum calculations were performed under effective mass approximation by assuming a spherically symmetric confining potential of finite depth. On the basis of the analytical solutions, the Schrödinger and Poisson equations' energies of states and corresponding wave functions were determined. The oscillator strength of each transition depends on the energy difference of two states and the dipole matrix element, i.e. wave functions of states. The effects of increasing the dot size in the presence of hydrogenic impurity on the oscillator strength of three series of transitions for a CdTe/ZnTe QD are presented in this paper.