• DOI:10.1103/PhysRevA.95.053601
• Corpus ID: 12802837

Internal structure and stability of vortices in a dipolar spinor Bose-Einstein condensate

@article{Borgh2017InternalSA,
  title={Internal structure and stability of vortices in a dipolar spinor Bose-Einstein condensate},
  author={M O Borgh and Justin Lovegrove and Janne Ruostekoski},
  journal={Physical Review A},
  year={2017},
  volume={95},
  pages={053601}
}

• M. Borgh, J. Lovegrove, J. Ruostekoski
• Published 31 January 2017
• Physics
• Physical Review A

We demonstrate how dipolar interactions can have pronounced effects on the structure of vortices in atomic spinor Bose-Einstein condensates and illustrate generic physical principles that apply across dipolar spinor systems. We then find and analyze the cores of singular vortices with non-Abelian charges in the point-group symmetry of a spin-3 $^{52}$Cr condensate. Using a simpler model system, we analyze the underlying dipolar physics and show how a characteristic length scale arising from the magnetic dipolar coupling interacts with the hierarchy of healing lengths of the s-wave scattering, and leads to simple criteria for the core structure: When the interactions both energetically favor the ground-state spin condition, such as in the spin-1 ferromagnetic phase, the size of singular vortices is restricted to the shorter spin-dependent healing length. Conversely, when the interactions compete (e.g., in the spin-1 polar phase), we find that the core of a singular vortex is enlarged by increasing dipolar coupling. We further demonstrate how the spin-alignment arising from the interaction anisotropy is manifest in the appearance of a ground-state spin-vortex line that is oriented perpendicularly to the condensate axis of rotation, as well as in potentially observable internal core spin textures. We also explain how it leads to interaction-dependent angular momentum in nonsingular vortices as a result of competition with rotation-induced spin ordering. When the anisotropy is modified by a strong magnetic field, we show how it gives rise to a symmetry-breaking deformation of a vortex core into a spin-domain wall.