Donor binding energies in group III-nitride-based quantum wells: influence of internal electric fields

We present calculations of the donor binding energy in GaN–AlxGa1−xN single quantum wells, including the effects of internal electric fields induced by spontaneous and piezoelectric polarizations. The variation of this energy versus position of the donor ion in the structure is of several tens of meV, i.e. much larger than for familiar quantum well systems. Realistic cases including the donor in the well and in the surrounding barriers are considered.