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arXiv · 1310.6989

Goldstone-mode Instability leading to Fragmentation in a Spinor Bose-Einstein Condensate

Yuki Kawaguchi
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Abstract

We apply the number-conserving Bogoliubov theory to spinor Bose-Einstein condensates and show that the Goldstone magnon leads instability leading to fragmentation. Unlike the dynamical instability, where modes with complex eigenfrequencies grow exponentially, here the zero-energy mode exhibits algebraic growth. We also point out that a small fraction of thermally excited atoms enhances the fragmentation dynamics.

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Yuki Kawaguchi. 2014-04-06. Goldstone-mode Instability leading to Fragmentation in a Spinor Bose-Einstein Condensate. https://doi.org/10.1103/physreva.89.033627

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