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Effect of thermal fluctuations on spin degrees of freedom in spinor Bose-Einstein condensates

W. V. Pogosov·K. Machida
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Abstract

We consider the effect of thermal fluctuations on rotating spinor F=1 condensates in axially-symmetric vortex phases, when all the three hyperfine states are populated. We show that the relative phase among different components of the order parameter can fluctuate strongly due to the weakness of the interaction in the spin channel. These fluctuations can be significant even at low temperatures. Fluctuations of relative phase lead to significant fluctuations of the local transverse magnetization of the condensate. We demonstrate that these fluctuations are much more pronounced for the antiferromagnetic state than for the ferromagnetic one.

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W. V. Pogosov, K. Machida. 2006-08-15. Effect of thermal fluctuations on spin degrees of freedom in spinor Bose-Einstein condensates. https://doi.org/10.1103/physreva.74.023624

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