Linear and nonlinear waves in edge channels.

Abstract

We have studied edge magnetoplasmons confined in the edge channels of a two-dimensional electron gas by analyzing the response of a voltage pulse at different distances from the excitation point. The transition from linear to nonlinear response with increasing voltage level is investigated as a function of the magnetic field (filling factor), the polarity of the applied pulse, and the temperature. Damping originates from the penetration of the wave into the bulk of the two-dimensional system which depends strongly on the width of the incompressible strips. The observed strong increase of the damping with temperature results from the smearing of the restricting incompressible strip. In the nonlinear regime the formation of shock waves can be observed.