Fractional Skyrmions and their molecules

TL;DR

This paper investigates a Skyrme-type model with quadratic potential, revealing stable fractional Skyrmion molecules with various baryon numbers, including novel configurations with fractional baryons, through numerical solutions.

Contribution

It introduces a model with quadratic potential and higher-order derivatives, demonstrating stable fractional Skyrmion molecules and their configurations, expanding understanding of topological solitons.

Findings

Stable solutions with baryon numbers 1 to 6

Molecules of fractional Skyrmions with baryon numbers 1/3 and 2/3

Configurations resembling beads on rings

Abstract

We study a Skyrme-type model with a quadratic potential for a field with $S^2$ vacua. We consider two flavors of the model, the first is the Skyrme model and the second has a sixth-order derivative term instead of the Skyrme term; both with the added quadratic potential. The model contains molecules of half Skyrmions, each of them is a global (anti-)monopole with baryon number 1/2. We numerically construct solutions with baryon numbers one through six, and find stable solutions which look like beads on rings. We also construct a molecule with fractional Skyrmions having the baryon numbers 1/3 + 2/3, by adding a linear potential term.