ISSN 0869-6632 (Print)
ISSN 2542-1905 (Online)

Журнал в журнале

Effect of external periodic force on the dynamics of thecharge domains in semiconductor superlattice

Periodic external signal effect on the collective dynamics of charge in semiconductor superlattice is studied. It is shown, that periodically­oscillating external electrical field can synchronize the transport of domains of the high density of charge as well as oscillations of electrical current flowing through the superlattice.

Synchronization of the system of two competing modes by external harmonic signal

Forced synchronization of self­oscillating system with two degrees of freedom is studied in the case when there are no resonance relations between eigenfrequencies and interaction of the modes has the form of mode competition. Stability conditions for the regimes of one­ and two­frequency oscillations are obtained analytically. The structure of synchronization tongues on the frequency–amplitude of external driving parameters plane is studied numerically.

On quasi­synchronous regimes in a phase lock loop with the second­order filter and approximate inclusion of the delay

For a typical phase lock loop with the second­order filter and delayed feedback, conditions of appearance and characteristics of regular and chaotic automodulation regimes are studied.

Chaos in volume free electron lasers

Mathematical model of Volume Free Electron Lasers (VFEL) is described. Some aspects and origins of VFEL chaotic dynamics are examined.

Parametric instability of autooscillator coupled with remote load i. Theory

At the autooscillator with weakly reflected remote load the number of one­frequency states –longitudinal modes – increases with the growth of the reflection coefficient and the length of the delay line. A mode of this kind can be unstable in some parameter regions. There can be two types of perturbations: a) the perturbations resulting in a slow evolution of principal mode amplitude and frequency; b) the perturbations in the form of two satellites which frequencies are symmetric from that of the principal mode.

On the problem of computation of the spectrum of spatial lyapunov exponents for the spatially extended beam plasma systems

The behavior of the Pierce diode has been considered from the point of view of the spatial Lyapunov exponents. The method of calculation of the spectrum of the spatial Lyapunov exponents for the electron spatial extended systems has been proposed. The autonomous dynamics of the Pierce diode as well as the behavior of two unidirectionally coupled Pierce diodes when the generalized synchronization is taken place have been considered.

Coupled van der pol and van der pol–duffing oscillators: dynamics of phase and computer simulation

Synchronization in the system of coupled nonidentical and nonisochronous van der Pol oscillators with dissipative and inertial type of coupling is discussed. Generalized Adler equation is obtained and investigated in the presence of all factors. Basic symmetry of the equation, with leads to equivalence of some physical factors, is displayed. Numerical investigation of parameters space of initial di?erential system is realized. Results of two methods are compared and discussed.

Billiard type systems and fermi acceleration

Systems of billiard types with perturbed boundaries are described. A generalized dispersing billiard – the Lorentz gas with the open horizon – and a focusing billiard in the form of stadium are considered. It is analytically and numerically shown that, if the billiard possesses the property of the developed chaos, the consequence of the boundary perturbation is the Fermi acceleration. However, the perturbation of the nearly integrable billiard system leads to a new interesting phenomenon – the separation of the billiard particles in their velocities.

Optimal chaos suppression and transition processes in сorrected multiparametrical oscillatory systems

In the work we present a two-stage scheme of optimal correction of the dynamic system’s parameters space aimed at the transformation of the system’s chaotic regime into the regular one through minimal intensity of the perturbation. The o?ered technique is based on combination of the optimal control theory methods with numerical tests of chaos suppression quality.

Numerical investigation of nonlinear nonstationary process in a chain of coupled gyro-backward-wave oscillators

In this work the nonlinear dynamics in a chain of unidirectionally coupled gyrobackward wave oscillators is studied. In coupled system, when the control parameters of each distributed system are changed, it is possible to show both a developed chaos dynamics and the regimes of stationary oscillations with one frequency.