A non-linear theory of acoustoelectric gain and current in piezoelectric semiconductors. III. The Gaussian electron distribution

For pt. II see A16173 of 1969, B7833 of 1969. The electron bunches formed in a periodic acoustic travelling wave are shown to have an approximately Gaussian shape at high flux levels. Plots are given, for Gaussian bunches, of the relevant gain parameters against a bunching parameter related to the half- width of the bunches. For 7*10 -2 Omega m cadmium sulphide the peak total flux gain and the peak first harmonic gain in a d.c. field of 4.8*10 5 v m -1 are reduced to 2.5% and 8% of their small signal values, respectively, at a flux level of the order of 10 8 wm -2 . In both cases the frequency at which the peak gain occurs is reduced to 25% of the small signal value.