Laser cooling and trapping of metastable helium: towards Bose–Einstein condensation
نویسنده
چکیده
Metastable triplet helium is an interesting atom, next to the alkalis and atomic hydrogen, to pursue Bose–Einstein condensation. In this paper an overview of the relevant physics of triplet helium and experimental progress in Amsterdam towards reaching Bose– Einstein condensation is described. 2001 Académie des sciences/Éditions scientifiques et médicales Elsevier SAS cold atoms / metastable helium / Bose–Einstein condensation / magnetic trap / evaporative cooling Refroidissement et piégeage d’atomes d’hélium métastable par laser : vers la condensation de Bose–Einstein Résumé. L’atome d’hélium placé dans son niveau triplet métastable est un candidat intéressant pour l’observation de la condensation de Bose–Einstein, déjà obtenue pour certains atomes alcalins et l’hydrogène. Dans cet article, nous décrivons les propriétés physiques pertinentes de l’hélium métastable, ainsi que les progrès récents réalisés dans notre groupe à Amsterdam vers l’observation de cette condensation. 2001 Académie des sciences/Éditions scientifiques et médicales Elsevier SAS atomes froids / hélium métastable / condensation de Bose–Einstein / piège magnétique / refroidissement par évaporation
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