Stark effect of donor binding energy in a self-assembled GaAs quantum dot subjected to a tilted electric field

We theoretically investigated the donor binding energy distribution with respect to the dopant positions in a self-assembled GaAs/AlGaAs quantum dot (QD) in the presence of a tilted electric field. It is found that there is a critical line in a doping plane, corresponding to zero Stark shift of the donor binding energy. At low electric fields, our work reveals that Stark shift of an on-center donor binding energy is a “purely” quadratic function of the electric field strength, irrespective of QD dimensions and field orientations. This scaling law permits us to indirectly estimate the impurity polarizability in a self-assembled QD.

► There is a critical line corresponding to zero shift of the donor binding energy.
► Dot dimensions and applied electric field affect significantly the critical line.
► Stark shift of on center donor binding energy is a quadratic function of the field.
► An indirect way to estimate the impurity polarizability has been reported.