Electron-phonon interaction in 2-dimensional systems - a microscopic approach

We present a calculation of the electron optical-phonon scattering rates in GaAs/AlAs quantum wells, based on a very accurate microscopic description of the phonon spectra. The results show that — besides the contribution of confined modes — a very large contribution originates from interface phonons of both GaAs-like and AlAs-like character. We then compare our results for phonon displacements and potentials, as well as for scattering rates, with those obtained from several macroscopic phonon models. We are therefore able to provide indications for selecting the model which allows the most appropriate simplified description of vibrations at the wavevectors relevant to the interaction with carriers.