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All-optical production and transport of a large $^6$Li quantum gas in a crossed optical dipole trap

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 نشر من قبل Christian Gross
 تاريخ النشر 2016
  مجال البحث فيزياء
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We report on an efficient production scheme for a large quantum degenerate sample of fermionic lithium. The approach is based on our previous work on narrow-line $ 2S_{1/2}rightarrow 3P_{3/2} $ laser cooling resulting in a high phase-space density of up to $3times10^{-4}$. This allows utilizing a large volume crossed optical dipole trap with a total power of $45,textrm{W}$, leading to high loading efficiency and $8times10^6$ trapped atoms. The same optical trapping configuration is used for rapid adiabatic transport over a distance of $25,textrm{cm}$ in $0.9,textrm{s}$, and subsequent evaporative cooling. With optimized evaporation we achieve a degenerate Fermi gas with $1.7times 10^{6}$ atoms at a temperature of $60 , textrm{nK}$, corresponding to $T/T_{text{F}}=0.16left(2 right)$. Furthermore, the performance is demonstrated by evaporation near a broad Feshbach resonance creating a molecular Bose-Einstein condensate of $3times10^5$ lithium dimers.

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