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arXiv · 1509.07213

Intense source of cold cesium atoms based on a two-dimensional magneto-optical trap with independent axial cooling and pushing

J. Q. Huang·X. S. Yan·C. F. Wu·J. W. Zhang·Y. Y. Feng·L. J. Wang
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Abstract

We report our studies on an intense source of cold cesium atoms based on a two-dimensional magneto-optical trap with independent axial cooling and pushing. The new-designed source, proposed as 2D-HP MOT, uses hollow laser beams for axial cooling and a thin pushing laser beam for cold atomic beam extraction. Regulated independently by the pushing beam, the atomic flux can be substantially optimized. The atomic flux maximum obtained in the 2D-HP MOT is $4.02\times 10^{10}$ atoms/s, increased by 60 percent compared to the traditional 2D$^+$ MOT in our experiment. Moreover, with the pushing power 10 $μ$W and detuning $0Γ$, the 2D-HP MOT can generate a rather intense cold cesium atomic beam with the concomitant light shift suppressed by 20 times in magnitude. The axial velocity distribution of the cold cesium beams centers at 6.8 m/s with a FMHW of about 2.8 m/s. The dependences of the atomic flux on the pushing power and detuning are studied. The experimental results are in good agreement with the theoretical model.

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J. Q. Huang, X. S. Yan, C. F. Wu, J. W. Zhang, Y. Y. Feng, L. J. Wang. 2015-09-24. Intense source of cold cesium atoms based on a two-dimensional magneto-optical trap with independent axial cooling and pushing. https://arxiv.org/abs/1509.07213

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