Bound vortex states and exotic lattices in multi-component Bose-Einstein condensates: The role of vortex-vortex interaction

TL;DR

This paper numerically investigates vortex-vortex interactions in multi-component Bose-Einstein condensates, revealing how pairwise interactions influence vortex lattice formations and bound states, with implications for experimental and superconducting systems.

Contribution

It demonstrates that pairwise vortex interactions determine vortex configurations and introduces a theoretical approach to analyze multi-component BEC vortex states.

Findings

Vortex-vortex interactions explain lattice structures.

Bound vortex states (dimers and trimers) are characterized.

Theoretical insights align with experimental observations.

Abstract

We numerically study the vortex-vortex interaction in multi-component homogeneous Bose-Einstein condensates within the realm of the Gross-Pitaevskii theory. We provide strong evidences that pairwise vortex interaction captures the underlying mechanisms which determine the geometric configuration of the vortices, such as different lattices in many-vortex states, as well as the bound vortex states with two (dimer) or three (trimer) vortices. Specifically, we discuss and apply our theoretical approach to investigate intra- and inter-component vortex-vortex interactions in two- and three-component Bose-Einstein condensates, thereby shedding light on the formation of the exotic vortex configurations. These results correlate with current experimental efforts in multi-component Bose-Einstein condensates, and the understanding of the role of vortex interactions in multiband superconductors.