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Enhanced observation time of magneto-optical traps using micro-machined non-evaporable getter pumps

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 نشر من قبل James McGilligan
 تاريخ النشر 2020
  مجال البحث فيزياء
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We show that micro-machined non-evaporable getter pumps (NEGs) can extend the time over which laser cooled atoms canbe produced in a magneto-optical trap (MOT), in the absence of other vacuum pumping mechanisms. In a first study, weincorporate a silicon-glass microfabricated ultra-high vacuum (UHV) cell with silicon etched NEG cavities and alumino-silicateglass (ASG) windows and demonstrate the observation of a repeatedly-loading MOT over a 10 minute period with a single laser-activated NEG. In a second study, the capacity of passive pumping with laser activated NEG materials is further investigated ina borosilicate glass-blown cuvette cell containing five NEG tablets. In this cell, the MOT remained visible for over 4 days withoutany external active pumping system. This MOT observation time exceeds the one obtained in the no-NEG scenario by almostfive orders of magnitude. The cell scalability and potential vacuum longevity made possible with NEG materials may enable inthe future the development of miniaturized cold-atom instruments.

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