Simplified microscopic model for electron–optical-phonon interactions in quantum wells

A simplified microscopic model of optical phonons in dimensionally confined structures is formulated and applied to calculate electron--optical-phonon scattering rates in GaAs/AlAs quantum wells. For this simplified model which circumvents performing a complicated ab initio calculation of the force constants at the interface, it is demonstrated that the resulting dispersion relation and scattering rates for electron--optical-phonon interactions agree very well with those obtained from detailed ab initio studies. It is also shown that for GaAs/AlAs structures, the macroscopic dielectric continuum model provides a good approximation to the scattering rate predicted by the microscopic models.