Electron–acoustic-phonon scattering rates in II–VI quantum dots: contribution of the macroscopic deformation potential

The electron–acoustic-phonon scattering process in spherical II–VI quantum dots is discussed. The quantized acoustic modes are described in terms of Lambʹs classical theory for the oscillations of a continuous sphere. The longitudinal spheroidal modes are included owing to their dominant contribution to the acoustic-phonon deformation potential (DP) scattering. We considered two mechanisms for the interaction between electrons and acoustic modes: microscopic DP, and macroscopic acoustic deformation, also called the ripple mechanism (RM). We also discuss the influence of the glass matrix on the electron–phonon coupling, which is particularly important for the RM. Our calculations show that the macroscopic deformation scattering rates become dominant by more than an order of magnitude, for a small dot radius. In general, the total scattering rate depends substantially on the choice of the mechanical boundary conditions and on the acoustic properties of the glass matrix.