Solitary acoustoelectric microwave domain in piezoelectric semiconductors

Negative differential conductivity stemming from piezoelectric coupling in semiconductors is shown to arouse a mm wide, high-amplitude acoustoelectric microwave packet moving at sound velocity. Because the electric permittivity is inferred to be renormalized to zero, all properties of this solution (but its width), including its vibrational frequency and amplitude, are shown to be shaped by the nonlinear piezoelectric interaction. An experiment is proposed to check the validity of this analysis. Possible implementation of an acoustoelectric generator is mentioned.