Anomalous relaxation and self-organization in non-equilibrium processes (2000)
Fatkullin, Ibrahim, Kladko, Konstantin, Mitkov, Igor, Bishop, A. R.
We study thermal relaxation in ordered arrays of coupled nonlinear elements with external driving. We find, that our model exhibits dynamic self-organization manifested in a universal...
Universal Scaling of Wave Propagation Failure in Arrays of Coupled Nonlinear Cells (1999)
Kladko, Konstantin, Mitkov, Igor, Bishop, A. R.
We study the onset of the propagation failure of wave fronts in systems of coupled cells. We introduce a new method to analyze the scaling of the critical external field at which fronts cease to...
Localized Structures in Nonlinear Lattices with Diffusive Coupling and External Driving (1998)
Mitkov, Igor, Kladko, Konstantin, Bishop, A. R.
We study the stabilization of localized structures by discreteness in one-dimensional lattices of diffusively coupled nonlinear sites. We find that in an external driving field these structures may...
Parametrically forced sine-Gordon equation and domain walls dynamics in ferromagnets (1998)
Zharnitsky, Vadim, Mitkov, Igor, Levi, Mark
A parametrically forced sine-Gordon equation with a fast periodic {\em mean-zero} forcing is considered. It is shown that $\pi$-kinks represent a class of solitary-wave solutions of the equation....
$\pi$-kinks in strongly ac driven sine-Gordon systems (1998)
Zharnitsky, Vadim, Mitkov, Igor, Grønbech-Jensen, Niels
We demonstrate that $\pi$-kinks exist in non-parametrically ac driven sine-Gordon systems if the ac drive is sufficiently fast. It is found that, at a critical value of the drive amplitude, there are...
Helicoidal instability of a scroll vortex in three-dimensional reaction-diffusion systems (1998)
We study the dynamics of scroll vortices in excitable reaction-diffusion systems analytically and numerically. We demonstrate that intrinsic three-dimensional instability of a straight scroll leads...
Dynamics of Wetting Fronts in Porous Media (1998)
Mitkov, Igor, Tartakovsky, Daniel M., Winter, C. Larrabee
We propose a new phenomenological approach for describing the dynamics of wetting front propagation in porous media. Unlike traditional models, the proposed approach is based on dynamic nature of the...
Higher order Shapiro steps in ac-driven Josephson junctions (1998)
Rasmussen, Kim O., Zharnitsky, Vadim, Mitkov, Igor, Grønbech-Jensen, Niels
We demonstrate that the well known phase-locking mechanism leading to Shapiro steps in ac-driven Josephson junctions is always accompanied by a higher order phase-locking mechanism similar to that of...
Tunable Pinning of Burst-Waves in Extended Systems with Discrete Sources (1998)
Mitkov, Igor, Kladko, Konstantin, Pearson, John E.
We study the dynamics of waves in a system of diffusively coupled discrete nonlinear sources. We show that the system exhibits burst waves which are periodic in a traveling-wave reference frame. We...
pi-kinks in Strongly AC Driven Sine-Gordon Systems (1998)
Vadim Zharnitsky, Igor Mitkov, Niels Grønbech-Jensen, Niels Gr��nbech-jensen
We demonstrate that ß-kinks can exist in non-parametrically AC driven sineGordon systems if the AC drive is sufficiently fast. It is found that, at a critical value of the drive amplitude, there are...