We calculate the binding energy of on- and off-center hydrogenic impurities in a parabolic quantum dot subjected to an intense high-frequency laser field. An exactly solvable model that replaces the actual Coulomb interaction with the donor by a non-local separable potential is introduced for calculating the binding energy. The separable potential allows us to solve the problem exactly and all ...

A characterization of the Si impurity in GaN is performed by Raman spectroscopy. Applying hydrostatic pressure up to 25GPa we study the behavior of the LO phonon-plasmon mode in a series of high mobility Si doped GaN films. In contrast to earlier results on unintentionally doped bulk GaN crystals no freeze out of the free carriers could be observed in Si doped samples. We find that Si is a shal...

The effect of the bulk Longitudinal-Optical (LO) phonon on the binding energy is investigated for a shallow donor impurity in a superlattice in the effective mass approximation by using the variational approach. The results are obtained as a function of parameters which characterize the superlattice and the position of the impurity center. The results show that the bulk Longitudinal-Optical (LO...