A high-flux 2D MOT source for cold lithium atoms

TL;DR

This paper presents a new 2D magneto-optical trap source for cold lithium atoms, achieving high flux and low velocity spread, with potential applications for other atomic species.

Contribution

The authors introduce a side-loaded 2D MOT source for lithium that significantly improves flux and velocity control compared to previous methods.

Findings

Maximum recapture rate of ~10^9 atoms/sec at 700 K

Total of up to 10^10 trapped atoms in the 3D MOT

Velocity spread of 11 m/s demonstrating monochromatic beam

Abstract

We demonstrate a novel 2D MOT beam source for cold 6Li atoms. The source is side-loaded from an oven operated at temperatures in the range 600<T<700 K. The performance is analyzed by loading the atoms into a 3D MOT located 220 mm downstream from the source. The maximum recapture rate of ~10^9 /s is obtained for T=700 K and results in a total of up to 10^10 trapped atoms. The recaptured fraction is estimated to be 30(10)% and limited by beam divergence. The most-probable velocity in the beam (alpha_z) is varied from 18 to 70 m/s by increasing the intensity of a push beam. The source is quite monochromatic with a full-width at half maximum velocity spread of 11 m/s at alpha_z=36 m/s, demonstrating that side-loading completely eliminates beam contamination by hot vapor from the oven. We identify depletion of the low-velocity tail of the oven flux as the limiting loss mechanism. Our approach is suitable for other atomic species.