Dynamics of polar-core spin vortices in a ferromagnetic spin-1 Bose-Einstein condensate

TL;DR

This paper models the dynamics of polar-core spin vortices in ferromagnetic spin-1 Bose-Einstein condensates, revealing their behavior as massive charged particles interacting via Coulomb forces, with insights from numerical simulations.

Contribution

It introduces a variational Lagrangian model for PCV dynamics, incorporating core interactions and coupling to spin waves, validated by numerical simulations.

Findings

PCVs behave as massive charged particles with Coulomb interactions

Numerical simulations show semi-quantitative agreement with the model

Core coupling to spin waves influences vortex dynamics

Abstract

A ferromagnetic spin-1 condensate supports polar-core spin vortices (PCVs) in the easy-plane phase. We derive a model for the dynamics of these PCVs using a variational Lagrangian approach. The PCVs behave as massive charged particles interacting under the two dimensional Coulomb interaction, with the mass arising from interaction effects within the vortex core. We compare this model to numerical simulations of the spin-1 Gross-Pitaevskii equations and find semi-quantitative agreement. In addition, the numerical results suggest that the PCV core couples to spin waves, and this affects the PCV dynamics even far from the core. We identify areas of further research that could extend the model of PCV dynamics presented here.