The single-beam MOT system based on the diffractive optical element offers a new route to develop compact cold atom sources, which, however, suffers from the low optical efficiency and unbalanced beam intensity distribution. To solve this issue, we developed a centimeter-scale dielectric metasurface optical chip with dynamic phase distributions, which was used to split a single incident laser beam into five separate ones with well-defined polarization states, high efficiency and uniform energy distributions. The measured diffraction efficiency of the metasurface is up to 47%. A single-beam MOT integrated with the metasurface optical chip was then used to trap the 87Rb atoms with numbers approximately 1.4 × 108 and temperatures approximately 7 μK, exhibiting better performance in cooling and trapping of atoms compared to the grating MOT and the early version of the metasurface MOTs.
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