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arXiv · 1211.5070

Chaotic saddles in nonlinear modulational interactions in a plasma

Rodrigo A. Miranda·Erico L. Rempel·Abraham C. -L. Chian
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Abstract

A nonlinear model of modulational processes in the subsonic regime involving a linearly unstable wave and two linearly damped waves with different damping rates in a plasma is studied numerically. We compute the maximum Lyapunov exponent as a function of the damping rates in a two-parameter space, and identify shrimp-shaped self-similar structures in the parameter space. By varying the damping rate of the low-frequency wave, we construct bifurcation diagrams and focus on a saddle-node bifurcation and an interior crisis associated with a periodic window. We detect chaotic saddles and their stable and unstable manifolds, and demonstrate how the connection between two chaotic saddles via coupling unstable periodic orbits can result in a crisis-induced intermittency. The relevance of this work for the understanding of modulational processes observed in plasmas and fluids is discussed.

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Rodrigo A. Miranda, Erico L. Rempel, Abraham C. -L. Chian. 2012-11-21. Chaotic saddles in nonlinear modulational interactions in a plasma. https://doi.org/10.1063/1.4766472

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