We study kink-antikink collisions in the one-dimensional non-integrable scalar phi^6 model. Although the single-kink solutions for this model do not possess an internal vibrational mode, our simulations reveal a resonant scattering structure, thereby providing a counterexample to the standard belief that existence of such a mode is a necessary condition for multi-bounce resonances in general kink-antikink collisions. We investigate the two-bounce windows in detail, and present evidence that this structure is caused by existence of bound states in the spectrum of small oscillations about a combined kink-antikink configuration.
Cite
@article{arxiv.1101.5951,
title = {Kink-antikink collisions in the phi^6 model},
author = {Patrick Dorey and Kieran Mersh and Tomasz Romanczukiewicz and Yasha Shnir},
journal= {arXiv preprint arXiv:1101.5951},
year = {2013}
}