Nonlinear interaction between surface acoustic waves and electrons in GaAs resonant-tunneling structures

A surface acoustic wave propagating within a resonant-tunneling structure modulates the rate of electron tunneling and creates a charge density wave in the depletion region of the structure. The charge wave acts piezoelectrically on the surface acoustic wave, thus providing a feedback mechanism. The interaction is strongly nonlinear because the tunneling rate is a nonlinear function of the potential drop across the quantum well of the resonant tunneling structure. We present an experimental and theoretical study of nonlinear effects in this distributed acoustoelectric system.