Electron Transport In Semiconductors Research Articles

High-frequency effects of ballistic electron transport in semiconductors

The response of a semiconductor to a high-frequency electric field is studied using a simple method of electron transport which includes both ballistic and dissipative effects. Ballistic motion appears as an inductive reactance. The significance of ballistic transport can be quantitatively expressed by the Q of the free-carrier plasma resonance. It is shown that the condition Q > 1 should hold for high-purity GaAs at low temperatures and that this condition could be verified by measurements at frequencies well below the plasma frequency.

Field dependence of mobility in gases

Ideas developed in problems of high-field electron transport in semiconductors have been extended to the case of gases. It is shown that nonlinearities in the electric current may occur at drift velocities comparable with the velocity of sound in the gas. This is in agreement with the recent experiments of Gee and Freeman on methane. Drift velocities much larger than the velocity of sound are needed for the nonlinearities to appear if the collisions are inelastic.