Collective modes of CP 3 skyrmion crystals in quantum Hall ferromagnets

@article{Ct2007CollectiveMO,
  title={Collective modes of CP 3 skyrmion crystals in quantum Hall ferromagnets},
  author={Ren{\'e} C{\^o}t{\'e} and D. B. Boisvert and J. Bourassa and Maxime Boissonneault and Herbert A. Fertig},
  journal={Physical Review B},
  year={2007},
  volume={76},
  pages={125320}
}
The two-dimensional electron gas (2DEG) in a bilayer quantum Hall system can sustain an interlayer coherence at filling factor $\ensuremath{\nu}=1$ even in the absence of tunneling between the layers. This system, which can be described as a quantum Hall pseudospin ferromagnet, has low-energy charged excitations which may carry textures in real spin or pseudospin. Away from filling factor $\ensuremath{\nu}=1$, a finite density of these is present in the ground state of the 2DEG and forms a… 
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