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arXiv · 1111.2557

Multi-site breathers in Klein-Gordon lattices: stability, resonances, and bifurcations

Abstract

We prove the most general theorem about spectral stability of multi-site breathers in the discrete Klein-Gordon equation with a small coupling constant. In the anti-continuum limit, multi-site breathers represent excited oscillations at different sites of the lattice separated by a number of "holes" (sites at rest). The theorem describes how the stability or instability of a multi-site breather depends on the phase difference and distance between the excited oscillators. Previously, only multi-site breathers with adjacent excited sites were considered within the first-order perturbation theory. We show that the stability of multi-site breathers with one-site holes change for large-amplitude oscillations in soft nonlinear potentials. We also discover and study a symmetry-breaking (pitchfork) bifurcation of one-site and multi-site breathers in soft quartic potentials near the points of 1:3 resonance.

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BibTeXRIS

Dmitry Pelinovsky, Anton Sakovich. 2013-01-12. Multi-site breathers in Klein-Gordon lattices: stability, resonances, and bifurcations. https://doi.org/10.1088/0951-7715%2F25%2F12%2F3423

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