A Theoretical Framework for the ab initio evaluation of the carrier energy relaxation in semiconductors under a high electric field
Ab initio analysis for initial process of Joule heating in semiconductors
We developed a theoretical framework for the ab initio evaluation of the carrier energy relaxation in semiconductors under a high electric field using a combination of the two-temperature modeland the boltzmann equation.We found a remarkable difference in the energyrelaxation processes of the electron and hole carriers due to the presence/absence of intervalley scattering processes and isotropic/anisotropic band structures in electrons and holes.The longitudinal acoustic and optical phonons at the zone boundary contribute to the energyrelaxation of electron carriers, whereas they contribute negligibly to that of the hole carriers.In addition, at the band edge, the energy relaxation rate is maximized for the electron carriers, whereas it is suppressed for the hole carriers.Our results lay the foundation for controlling the thermal generation in semiconductors by material design.
