Properties of quasi-soliton states in nonlinear media under local high-frequency irradiation. Analytic description and comparison with numerical simulations

Abstract

Spatially localized excitation of a one-dimensional magnetic system in an external high-frequency field is studied analytically (collective variable method) and numerically. The dependences of the amplitude of local quasi-soliton states on the amplitude of this field for different frequencies and damping in the system are found for the case of direct application of a localized magnetic field. The field dependence is found to have hysteresis and “instability windows” in the stationary states. Within these instability regions, the excitations become nonstationary: they are accompanied by additional periodic nutation of the magnetization vector. Here such nonlinear dynamics phenomena as period doubling and transitions to chaos are observed.