Nonlinear electrical conductivity of a semiconductor channel under conditions of strong electron–phonon relaxation
Abstract
The nonlinear electrical conductivity of an impurity semiconductor channel (of diameter d) is investigated in the case of strong screening of the electric field: li, rD ≪d (li, is the elastic mean free path of electrons, and rD is the screening radius of the electric field in the semiconductor). It is shown that under conditions when the characteristic length of the emission of phonons by electrons is small in comparison with the channel length L, and other inelastic relaxation processes are insignificant, the generation of phonons produces current jumps in the channel at voltages that are multiples of the phonon emission energy ħω0. The possibility of determining the energy dependence of the inelastic electron-scattering time τ(ϵ) in the energy interval ϵ < ħω0. from the form of the first derivative of the current-voltage that is characteristic of a microcontact is demonstrated. The transport-current jumps predicted in the article have recently been observed experimentally.