Kinks bounded by fermions

TL;DR

This paper introduces a new fermion-mediated interaction mechanism between solitons in 1+1 dimensional scalar field theories, leading to stable multi-soliton bound states with potential applications across various physical systems.

Contribution

It demonstrates a novel fermion exchange interaction that results in stable multi-soliton configurations in scalar field models coupled with Dirac fermions.

Findings

Fermion exchange induces attractive forces between solitons.

Stable multi-soliton bound states are formed due to this interaction.

The mechanism is applicable to a wide range of physical systems.

Abstract

We present and study new mechanism of interaction between the solitons based on the exchange interaction mediated by the localized fermion states. As particular examples, we consider solutions of simple 1+1 dimensional scalar field theories with self-interaction potentials, including sine-Gordon model and the polynomial $\phi^4$, $\phi^6$ models, coupled to the Dirac fermions with back-reaction. We discover that there is an additional fermion exchange interaction between the solitons, it leads to the formation of static multi-soliton bound states. Further, we argue that similar mechanisms of formation of stable coupled multi-soliton configurations can be observed for a wide class of physical systems.