Electrical excitation of shock and solitonlike waves in two-dimensional electron channels

Abstract

We study the electrical excitation of nonlinear plasma waves in heterostructures with two-dimensional electron channels and with split gates, and the propagation of these waves using hydrodynamic equations for electron transport coupled with two-dimensional Poisson equation for self-consistent electric potential. The term related to electron collisions with impurities and phonons as well as the term associated with viscosity are included into the hydrodynamic equations. We demonstrate the formation of shock and solitonlike waves as a result of the evolution of a strongly nonuniform initial electron density distribution. It is shown that the shock wave front and the shape of solitonlike pulses pronouncedly depend on the coefficient of viscosity, the thickness of the gate layer, and the nonuniformity of the donor distribution along the channel. The electron collisions result in the damping of the shock and solitonlike waves, while they do not markedly affect the thickness of the shock wave front.