Stability and dynamics of massive vortices in two-component Bose-Einstein condensates

TL;DR

This paper investigates the stability and dynamics of vortex-bright structures in two-component Bose-Einstein condensates, especially focusing on large inter-component interactions and their associated instabilities and evolution.

Contribution

It extends the analysis of vortex-bright structures beyond near-integrable regimes, providing new insights into their stability and dynamic behavior at large interaction strengths.

Findings

Identification of dynamical instabilities for certain parameters

Development of a particle model to predict stability and dynamics

Observation of a novel instability scenario ejecting multiple vortex-bright structures

Abstract

The study of structures involving vortices in one component and bright solitary waves in another has a time-honored history in two-component atomic Bose-Einstein condensates. In the present work, we revisit this topic extending considerations well-past the near-integrable regime of nearly equal scattering lengths. Instead, we focus on stationary states and spectral stability of such structures for large values of the inter-component interaction coefficient. We find that the state can manifest dynamical instabilities for suitable parameter values. We also explore a phenomenological, yet quantitatively accurate upon suitable tuning, particle model which, in line also with earlier works, offers the potential of accurately following the associated stability and dynamical features. Finally, we probe the dynamics of the unstable vortex-bright structure, observing an unprecedented, to our knowledge, instability scenario in which the oscillatory instability leads to a patch of vorticity that harbors and eventually ejects multiple vortex-bright structures.