Considering the three-dimensional confinement of the electrons and holes
and the strong built-in electric field (BEF) in the wurtzite
InGaN strained coupled quantum dots (QDs), the positively charged
donor bound exciton states and interband optical transitions are
investigated theoretically by means of a variational method. Our
calculations indicate that the emission wavelengths sensitively
depend on the donor position, the strong BEF, and the structure
parameters of the QD system.