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arXiv · 1409.2350

Two-stage magneto-optical trapping and narrow-line cooling of $^6$Li atoms to high phase-space density

Jimmy Sebastian·Christian Gross·Ke Li·Huat Chai Jaren Gan·Wenhui Li·Kai Dieckmann
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Abstract

We report an experimental study of peak and phase-space density of a two-stage magneto-optical trap (MOT) of 6-Li atoms, which exploits the narrower $2S_{1/2}\rightarrow 3P_{3/2}$ ultra-violet (UV) transition at 323 nm following trapping and cooling on the more common D2 transition at 671 nm. The UV MOT is loaded from a red MOT and is compressed to give a high phase-space density up to $3\times 10^{-4}$. Temperatures as low as 33 $μ$K are achieved on the UV transition. We study the density limiting factors and in particular find a value for the light-assisted collisional loss coefficient of $1.3 \pm0.4\times10^{-10}\,\textrm{cm}^3/\textrm{s}$ for low repumping intensity.

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Jimmy Sebastian, Christian Gross, Ke Li, Huat Chai Jaren Gan, Wenhui Li, Kai Dieckmann. 2014-09-08. Two-stage magneto-optical trapping and narrow-line cooling of $^6$Li atoms to high phase-space density. https://doi.org/10.1103/physreva.90.033417

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