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arXiv · 0811.4456

Extreme tunability of interactions in a $^7$Li Bose-Einstein condensate

Scott E. Pollack·D. Dries·M. Junker·Y. P. Chen·T. A. Corcovilos·R. G. Hulet
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Abstract

We use a Feshbach resonance to tune the scattering length a of a Bose-Einstein condensate of 7Li in the |F = 1, m_F = 1> state. Using the spatial extent of the trapped condensate we extract a over a range spanning 7 decades from small attractive interactions to extremely strong repulsive interactions. The shallow zero-crossing in the wing of the Feshbach resonance enables the determination of a as small as 0.01 Bohr radii. In this regime, evidence of the weak anisotropic magnetic dipole interaction is obtained by comparison with different trap geometries.

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Scott E. Pollack, D. Dries, M. Junker, Y. P. Chen, T. A. Corcovilos, R. G. Hulet. 2009-03-06. Extreme tunability of interactions in a $^7$Li Bose-Einstein condensate. https://doi.org/10.1103/physrevlett.102.090402

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