Phonon energy dependence of scattering in quasihyphen;twohyphen;dimensional electron gases at low temperature

摘要

We investigate the scattering of electrons in a quasihyphen;twohyphen;dimensional electron gas by acoustic phonons at low temperatures. In contrast to scattering at high temperatures, we find that at low temperatures the average scattering rate is dominated by phonon modes with energies much larger thankT. An analytic calculation of either the energyhyphen;loss rate or the mobility depends on approximations which are valid only for small phonon wave numbers. Because of the contribution of highhyphen;energy phonons, these approximations remain inappropriate to much lower temperatures than previously supposed. For most cases, we find that the approximate analytic solution differs significantly from a more accurate solution obtained by numerical integration.