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Optical and evaporative cooling of cesium atoms in the gravito-optical surface trap

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 نشر من قبل Rudi Grimm
 تاريخ النشر 2000
  مجال البحث فيزياء
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We report on cooling of an atomic cesium gas closely above an evanescent-wave atom mirror. At high densitities, optical cooling based on inelastic reflections is found to be limited by a density-dependent excess temperature and trap loss due to ultracold collisions involving repulsive molecular states. Nevertheless, very good starting conditions for subsequent evaporative cooling are obtained. Our first evaporation experiments show a temperature reduction from 10muK down to 300nK along with a gain in phase-space density of almost two orders of magnitude.



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