Spontaneous Magnetic Ordering in a Ferromagnetic Spinor Dipolar Bose-Einstein Condensate
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.
Cite
@article{arxiv.0909.0565,
title = {Spontaneous Magnetic Ordering in a Ferromagnetic Spinor Dipolar Bose-Einstein Condensate},
author = {Yuki Kawaguchi and Hiroki Saito and Kazue Kudo and Masahito Ueda},
journal= {arXiv preprint arXiv:0909.0565},
year = {2011}
}
Comments
Extended version of the previous one; 19 pages, 18 figures