INTERFACE PHONONS IN SPHERICAL GAAS AL-X GA1-XAS QUANTUM DOTS/

Within the framework of the dielectric continuum model, the interface phonon frequencies for spherical GaAs/AlxGa1-xAs quantum dots are obta ined as functions of the alloy composition in the range x=0.2-1.0. By imposing electrostatic boundary conditions, the two interface phonon f requencies are calculated for the first three modes. The frequency beh avior of the different modes is foundto be similar. However, for each mode one of the phonon frequencies is found to be strongly dependent o n x. It is demonstrated that these phonon modes play an important sole in determining resonant optical absorption of quantum dots.