Evidence of the Electron Velocity Runaway in Polar Semiconductors
A new approach of treating the Boltzmann equation for electron-polar optical phonon (P.O.P.) interaction scattering is described. It is based on electron wave vector direction conservation for the high electron energy P.O.P. scattering, what gives a simple form to the collision integral. Afterwards, information on the distribution function is derived from a Fokker-Planck-like equation. It is shown that the tail of the distribution function exhibits a minimum before saturating up to infinity. The possibility of this velocity runaway is then discussed.
KeywordsPhysical Review High Electron Energy Minimum Curve Polar Optical Phonon Electric Field Direction
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