Quantum size effect on excitons in zinc-blende GaN/AlN quantum dot

Within the framework of effective-mass approximation, exciton states confined in zinc-blende GaN/AlN quantum dot (QD) are investigated by means of a variational approach, including three-dimensional confinement of the electron and hole in the QD and finite band offsets. Numerical results show that the exciton binding energy and the interband emission energy are both decreased when QD height (or radius) is increased. Our theoretical results are in agreement with the experimental measurements.