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arXiv · 2409.05436

Kink movement on a periodic background

Tomasz Dobrowolski·Jacek Gatlik·Panayotis G. Kevrekidis
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Abstract

The behavior of the kink in the sine-Gordon (sG) model in the presence of periodic inhomogeneity is studied. An ansatz is proposed that allows for the construction of a reliable effective model with two degrees of freedom. Effective models with excellent agreement with the original field-theoretic partial differential equation are constructed, including in the non-perturbative region and for relativistic velocities. The numerical solutions of the sG model describing the evolution of the kink in the presence of a barrier as well as in the case of a periodic heterogeneity under the potential additional influence of a switched bias current and/or dissipation were obtained. The results of the field equation and the effective models were compared. The effect of the choice of initial conditions in the field model on the agreement of the results with the effective model is discussed.

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Tomasz Dobrowolski, Jacek Gatlik, Panayotis G. Kevrekidis. 2024-12-27. Kink movement on a periodic background. https://doi.org/10.1103/physreve.111.024203

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