We show that spinor Bose-Einstein condensates not only have line-like vortex excitations, but in general also allow for point-like topological excitations, i.e., skyrmions. We discuss the static and dynamic properties of these skyrmions for spin-1/2 and ferromagnetic spin-1 Bose gases.

arXiv:cond-mat/0002375Feb 24, 20000 citations

Skyrmion excitation in a two-dimensional spinor Bose-Einstein condensate

Hui Zhai, Wei-Qiang Chen, Zhan Wei Xu +1 more

We study the properties of coreless vortices (skyrmions) in spinor Bose-Einstein condensates. We find that this excitation is always energetically unstable, it always decays to an uniform spin texture. We obtain the skyrmion energy as a function of its size and position, a key quantity in understanding the decay process. We also point out that the decay rate of a skyrmion with high winding number will be slower. The interaction between skyrmions and other excitation modes are also discussed.

arXiv:cond-mat/0210397Physical Review AOct 3, 200332 citations