Fig. 1. (a) Experimental setup. Raman lasers 1–4 and an optical pumping laser are applied to implement the Raman sideband cooling. Dipole lasers 1 and 2 are applied to construct the crossed dipole trap. Bias coils are used to produce the external magnetic field. The probe laser passes through the trapped atoms, and the number and density of atoms are measured using the absorption image technique. (b) Experimental sequence for manipulation of the magnetic field, PA laser, and probe laser of absorption image.

Fig. 2. (a) PA spectrum of the v = 10 vibrational level of Cs₂ long-range 0g− state without the magnetic field. (b) The number of atoms as a function of the frequency detuning of the PA laser with the magnetic fields of 87 G (red dots), 96 G (violet dots), 108 G (green dots), and 120 G (navy dots) for J = 2. The solid curves are the fittings using a Lorentzian function.

Fig. 3. (a) Theoretical scattering length. (b) PA rate coefficient as a function of magnetic field for rotational level J = 2 in v = 10. The dots are experimental data. The solid lines are the results of theoretical calculation. The dashed lines show the PA rate coefficient without the magnetic field.