Soliton Dynamics in Interacting Double SSH chains

The phi^4 model is a model that describes Su-Schrieffer-Heeger (SSH) model and kinks therein. The dynamics of SSH model such as kink-antikink solitons also can be studied with phi^4 model. In this work, we considered a double SSH chain model having an interchain coupling and studied kink-antikink collisions using double phi^4 model. In this model, there are four degenerate groundstates and three types of chiral solitons; right chiral, left chiral and achiral solitons. We investigated various types of soliton collisions using these three types of chiral solitons. We found that a soliton pair can switch their residing chain after the collision when the initial collision velocity is larger than a critical velocity. Using the collective coordinates method, we explained the collision mechanism as well as the various types of soliton collision operation. We expect that our work will help to understand the experimental soliton collision reported in atomic indium chains on the silicone substrate and give an insight to the collisions of topological objects in general topological systems.