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arXiv · 0909.0565

Spontaneous Magnetic Ordering in a Ferromagnetic Spinor Dipolar Bose-Einstein Condensate

Yuki Kawaguchi·Hiroki Saito·Kazue Kudo·Masahito Ueda
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Abstract

We study the spin dynamics in a spin-1 ferromagnetic Bose-Einstein condensate with magnetic dipole-dipole interaction (MDDI) based on the Gross-Pitaevskii and Bogoliubov theories. We find that various magnetic structures such as checkerboards and stripes emerge in the course of the dynamics due to the combined effects of spin-exchange interaction, MDDI, quadratic Zeeman and finite-size effects, and non-stationary initial conditions. However, the short-range magnetic order observed by the Berkeley group [Phys. Rev. Lett. {\bf 100}, 170403 (2008)] is not fully reproduced in our calculations; the periodicity of the order differs by a factor of three and the checkerboard pattern eventually dissolves in our numerical simulations. Possible reasons for the discrepancy are discussed.

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Yuki Kawaguchi, Hiroki Saito, Kazue Kudo, Masahito Ueda. 2010-06-24. Spontaneous Magnetic Ordering in a Ferromagnetic Spinor Dipolar Bose-Einstein Condensate. https://doi.org/10.1103/physreva.82.043627

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