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Effect of cold collisions on spin coherence and resonance shifts in a magnetically trapped ultra-cold gas

D. M. Harber·H. J. Lewandowski·J. M. McGuirk·E. A. Cornell
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Abstract

We have performed precision microwave spectroscopy on ultra-cold Rb-87 confined in a magnetic trap, both above and below the Bose-condensation transition. The cold collision shifts for both normal and condensed clouds were measured, which allowed the intra- and inter-state density correlations (characterized by sometimes controversial "factors of two") to be determined. Additionally, temporal coherence of the normal cloud was studied, and the importance of mean-field and velocity-changing collisions in preserving coherence is discussed.

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D. M. Harber, H. J. Lewandowski, J. M. McGuirk, E. A. Cornell. 2002-11-15. Effect of cold collisions on spin coherence and resonance shifts in a magnetically trapped ultra-cold gas. https://doi.org/10.1103/physreva.66.053616

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