Numerical Simulation of Topological Solitons Dynamics in Coupled Sine-Gordon Chains and Interaction with Localized Impurities

Abstract

We consider the numerical simulation of the dynamics of topological solitons in coupled Sine-Gordon chains. Oscillating bound states and mutual pinning of solitons belonging to different chains are observed. The interaction of pairs of solitons with localized impurities is also investigated. Symmetrical and antisymmetrical impurity modes are excited in the case of an attractive impurity with the same strength in both chains. We find that the critical velocity below, which resonant interactions between the solitons and impurity modes take place, increases as we move from the highly repulsive state to the highly attractive state. In the case of attractive impurities with different strengths, the pair of solitons can be either captured, separated or transmitted with the formation of a moving bound state afterwards.