18th International Conference on Atomic Physics
We use precision microwave spectroscopy of magnetically trapped, ultra-cold 87Rb to characterize intra- and inter-state density correlations. The cold collision shifts for both normal and condensed clouds are measured. The results verify the presence of the sometimes controversial "factors of two", in normal-cloud mean-field energies, both within a particular state and between two distinct spin species. One might expect that as two spin species decohere, the inter-state factor of two would revert to unity, but the associated frequency chirp one naively expects from such a trend is not observed in our data.
Harber, D. M.; Lewandowski, H. J.; McGuirk, J. M.; and Cornell, Eric A., "The Mystery of the Ramsey Fringe that Didn’t Chirp" (2002). Physics Faculty Contributions. 16.