Non-ohmic transport and phonon amplification in polar semiconductors

A displaced maxwellian model for hot electrons in polar semiconductors is used to analyse the detailed time dependence of optical and acoustic phonon disturbances in n-InSb at low temperatures. No nonlinear phonon processes are considered, restricting the applicability of the present theory to small phonon disturbances (optical phonons) or to the initial stages of strong acoustic phonon instabilities.