Relation between dipole moment and radiative lifetime in interface fluctuation quantum dots

A relation between dipole moment and radiative lifetime of quantum dots for arbitrary indices of refraction of the quantum dot and surrounding medium is derived. As limiting cases several formulas already in use are obtained and their correct use is discussed. We proceed to discuss the relation between dipole moment and radiative lifetime in interface fluctuation quantum dots (IFQD's) taking into account nonsphericity effects. This introduces a dependence on the light propagation direction. We calculate how to account for the nonsphericity of an interface fluctuation quantum dot depending on its diameter and well thickness and find that the lifetime of a typical IFQD with a 50 nm diameter is reduced by about 10% due to nonsphericity effects.