In this article, we theoretically calculated the hot electron energy relaxation induced by longitudinal acoustic (LA) phonons, longitudinal optical (LO) phonons and importantly two-transverse acoustic (2TA) phonons in two-dimensional SiGe quantum wells, by incorporating dynamic screening effect in LA phonon scattering and hot-phonon effect in LO phonon scattering mechanisms. At the low-temperature regime, the ELR is found to be dominated by LA phonons and at higher temperature ELR is dominated by LO phonons. In the intermediate temperature range, 2TA phonon scattering mechanism is very important and we incorporated in our calculations. The unscreened longitudinal acoustic (LA) phonon due to deformation potential (DP) coupling is dominant over the screened acoustic piezoelectric phonon contribution. At higher temperatures, there is a crossover from ELR due to LA phonons to ELR due to longitudinal optical (LO) phonons with the cross-over temperature being about Te∼40K. The LA phonon screening effect and hot phonon effect is demonstrated to reduce ELR significantly. In the intermediate temperature range (30 K< < 90 K), 2TA phonon scattering mechanism is found to be dominating.
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