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arXiv · 0807.3129

Bose-Einstein condensates of polar molecules: anisotropic interactions = anisotropic mass

Andrei Derevianko
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Abstract

So far the theory of Bose-Einstein condensates (BEC) of polar molecules was based on an ad hoc generalization of equations for spherical atoms. Here I adopt a rigorous pseudo-potential approach to low-energy dipolar interactions and derive a non-linear mean-field Schrodinger equation for a harmonically-trapped condensate. I show that, effectively, the dipolar interactions alter molecular mass. The resulting effective mass is anisotropic: to the leading order the mass is altered only for the motion along the polarizing field. For a typical BEC of spin-polarized magnetically-interacting alkali-metal atoms the effective atomic mass is reduced by 10% from its bare value. For a BEC of polar molecules the mass may be reduced by a factor of a 1,000.

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Andrei Derevianko. 2008-07-20. Bose-Einstein condensates of polar molecules: anisotropic interactions = anisotropic mass. https://arxiv.org/abs/0807.3129

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