QUANTUM DOTS UNDER ELECTRIC AND MAGNETIC-FIELDS - IMPURITY-RELATED ELECTRONIC-PROPERTIES

A systematic study of the ground-state binding energies of a hydrogeni c impurity in quantum dots subjected to external electric and magnetic fields is presented. The quantum dot is modelled by superposing a lat eral parabolic potential and a square-well potential and the energies are calculated via a variational approach within the effective-mass ap proximation. The interplay between the confinement effects due to the applied fields and the quantum-size confinements on the binding energi es is analysed. The role played by the impurity position along the wel l direction on the impurity energies is also discussed. We have shown that by changing the strength of the external electric and magnetic fi elds, a large spread in the range of the donor binding energy may be o btained, for a particular choice for the lateral confinement. The pres ented results could be used to tailor energy states in optoelectronic devices. (C) 1997 American Institute of Physics.