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Homotopy Theory of Topological Defects in Spinor Condensates

Yunbo Zhang·Harri Mäkelä·Kalle-Antti Suominen
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Abstract

We investigate the topological defects in atomic spin-1 and spin-2 Bose-Einstein condensates by applying the homotopy group theory. With this rigorous approach we clarify the previously controversial identification of symmetry groups and order parameter spaces for the spin-1 case, and show that the spin-2 case provides a rare example of a physical system with non-Abelian line defects, and the possibility to have winding numbers of 1/3 and its multiples.

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Yunbo Zhang, Harri Mäkelä, Kalle-Antti Suominen. 2003-05-21. Homotopy Theory of Topological Defects in Spinor Condensates. https://arxiv.org/abs/cond-mat/0305489

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