EFFECT OF BULK DISPERSION ON THE ELECTRON OPTICAL-PHONON INTERACTION IN A SINGLE-QUANTUM-WELL

The interaction of electrons with GaAs optical phonons is investigated for a single GaAs/AlAs quantum well using the hybrid model of optical phonons, which incorporates bulk-mode dispersion. We predict resonances in the individual hybrid scattering rates as a function of well width corresponding to wave vectors where the modes anticross. Nevertheless, although the physics is quite different, we find that the total scattering rate is insensitive to the value of the bulk dispersion, and is given to an excellent approximation by the dielectric continuum model, for both intrasubband and intersubband scattering processes. We conclude, in accord with recent results of lattice dynamics, that for the evaluation of scattering rates, the dielectric continuum model provides a very good approximation.