The possibility of existence of electromagnetic solitons is explored based on the coupled equations for the classical function of electron distribution in carbon nanotubes and the Maxwell equations for the electromagnetic field. The solitons emerge due to a concerted change in the classical distribution function and the electric field generated by the nonequilibrium electrons of a carbon nanotube. An efficient equation was obtained to describe the electromagnetic-field dynamics. The data of numerical calculations indicating the existence of solitons are given.

Electromagnetic solitons in a system of carbon nanotubes

Surface magnetoplasma waves at the interface between a plasma-like medium and a metal in the Voigt geometry

An investigation is made of nonlinear oscillations of the field and current in semiconductor superlattices driven by strong terahertz radiation. Regimes of periodic, quasi-periodic, and stochastic self-oscillations are determined and mechanisms for their formation are discussed. It is shown that the self-oscillation spectra are many-valued functions of the external field amplitude and the static field in them is either absent, weak, or fractionally quantized. Previously predicted states of self-induced superlattice transparency and dynamic electron localization are destroyed as a result of the evolution of dissipative and parametric instabilities and can only be observed in transient processes whose duration decreases with increasing electron concentration.

Self-Oscillations in Semiconductor Superlattices

The possibility of forming solitons in zigzag carbon nanotubes is investigated using the coupled equations for the classical function of the electron distribution and the Maxwell equations for an electromagnetic field. It is demonstrated that the solitons are generated as a result of correlated changes in the classical distribution function and the electric field induced by nonequilibrium electrons of a carbon nanotube. The effective equation describing the dynamics of the electromagnetic field is derived. The existence of solitons is confirmed by the results of numerical calculations. The characteristics of solitons are investigated as a function of the diameter of zigzag carbon nanotubes.

Electromagnetic solitons in bundles of zigzag carbon nanotubes

A model of the energy spectrum of a superlattice based on graphene overlying a substrate of periodically arranged layers of different insulators is proposed. For such a structure, the dc current component induced by an elliptically polarized electromagnetic wave and directed normally to the sweeping field is calculated. The dependence of the transverse current density on the strengths of the sweeping electric field and the elliptically polarized wave components is analyzed.

Aleksandr P. Tetervov

Papers

High-frequency properties of semiconductors with superlattices