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arXiv · 0803.1167

Photoassociation of a Bose-Einstein Condensate near a Feshbach Resonance

M. Junker·D. Dries·C. Welford·J. Hitchcock·Y. P. Chen·R. G. Hulet
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Abstract

We measure the effect of a magnetic Feshbach resonance (FR) on the rate and light-induced frequency shift of a photoassociation resonance in ultracold $^7$Li. The photoassociation-induced loss rate coefficient, $K_p$, depends strongly on magnetic field, varying by more than a factor of 10$^4$ for fields near the FR. At sufficiently high laser intensities, $K_p$ for a thermal gas decreases with increasing intensity, while saturation is observed for the first time in a Bose-Einstein condensate. The frequency shift is also strongly field-dependent and exhibits an anomalous blue-shift for fields just below the FR.

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M. Junker, D. Dries, C. Welford, J. Hitchcock, Y. P. Chen, R. G. Hulet. 2008-07-09. Photoassociation of a Bose-Einstein Condensate near a Feshbach Resonance. https://doi.org/10.1103/physrevlett.101.060406

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