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arXiv · 1806.06510

Recoil-ion momentum spectroscopy of photoionization of cold rubidium atoms in a strong laser field

Renyuan Li·Junyang Yuan·Xinya Hou·Shuai Zhang·Zhiyuan Zhu·Yixuan Ma·Qi Gao·Zhongyang Wang·T. -M. Yan·Chaochao Qin·Yizhu Zhang·Xincheng Wang·Matthias Weidemüller·Y. H. Jiang
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Abstract

We study photoionization of cold rubidium atoms in a strong infrared laser field using a magneto-optical trap (MOT) recoil ion momentum spectrometer. Three types of cold rubidium target are provided, operating in two-dimension (2D) MOT, 2D molasses, and 3D MOT with densities in the orders of $10^7$ atoms/cm$^3$, $10^8$ atoms/cm$^3$, and $10^9$ atoms/cm$^3$, respectively. The density profile and the temperature of 3D MOT are characterized using the absorption imaging and photoionization. The momentum distributions of Rb$^+$ created by absorption of two- or three-photon illuminate a dipole-like double-peak structure, in good agreement with the results in the strong field approximation. The yielding momentum resolution of $0.12 \pm 0.03$ a.u. is achieved in comparison with theoretical calculations, exhibiting the great prospects for the study of electron correlations in alkali metal atoms through interaction with strong laser pulses.

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Renyuan Li, Junyang Yuan, Xinya Hou, Shuai Zhang, Zhiyuan Zhu, Yixuan Ma, Qi Gao, Zhongyang Wang, T. -M. Yan, Chaochao Qin, Yizhu Zhang, Xincheng Wang, Matthias Weidemüller, Y. H. Jiang. 2018-06-18. Recoil-ion momentum spectroscopy of photoionization of cold rubidium atoms in a strong laser field. https://arxiv.org/abs/1806.06510

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