GIANT OSCILLATIONS OF ACOUSTOELECTRIC CURRENT IN A QUANTUM CHANNEL

A theory of de electric current induced in a quantum channel by a prop agating surface acoustic wave (acoustoelectric current) is worked out. The first observation, to our knowledge, of the acoustoelectric curre nt in such a situation was reported by J. M. Shilton et al., J. Phys. Condens. Matter 8, L337 (1996). The authors observed a very specific b ehavior of the acoustoelectric current in a quasi-one-dimensional chan nel defined in a GaAs-AlxGa1-xAs heterostructure by a split-gate deple tion-giant oscillations as a function of the gate voltage. Such a beha vior was qualitatively explained by an interplay between the energy-mo mentum conservation law for the electrons in the upper transverse mode with a finite temperature splitting of the Fermi level. In the presen t paper, a more detailed theory is developed, and important limiting c ases are considered.