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

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 نشر من قبل David M. Harber
 تاريخ النشر 2002
  مجال البحث فيزياء
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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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