Fig. 1. Hyperfine structure of ⁸⁵Rb D₂ line

Fig. 2. Light path for cooling Rb atoms

Fig. 3. Schematic of MOTRIMS setup

Fig. 4. Detection results of absorption imaging method. (a) Absorption image; (b) reference image;(c) background image; (d) optical thickness image

Fig. 5. Imaging sequence control for density measurement (dotted line means opening and solid line means closing)

Fig. 6. Number of Rb⁺ versus gradient magnetic field

Fig. 7. Atomic mass distributions at different times, corresponding to the direction of the instrument. (a) Distribution of atomic group at 2 ms; (b) Gaussian fitting of atomic group at 2 ms in y direction; (c) Gaussian fitting of atomic group at 2 ms in z direction; (d) distribution of atomic group at 11 ms; (e) Gaussian fitting of atomic group at 11 ms in y direction; (f) Gaussian fitting of atomic group at 11 ms in z direction

Fig. 8. Momentum spectra of hot vapor target and 3D MOT target (dotted line is the momentum distribution of Rb⁺ of hot vapor target, and right vertical axis is the counts of hot vapor target; solid line is the TOF spectrum and momentum distribution of Rb⁺ of 3D MOT target, left vertical axis is the counts of 3D MOT target, and the horizontal axis on the top is the TOF of 3D MOT target)

Fig. 9. Rb⁺ momentum distribution of molasses target after interaction with the strong field. (a) Momentum distribution in x and z directions; (b) momentum distribution in z direction in linear coordinates; (c) momentum distribution in z direction in log coordinates