Dual-species optical tweezer for Rb and K atoms

The optical tweezer experiment with neutral atoms is a focal topic in cold-atom physics due to its significant potential in quantum computing and simulation. Here we present the realization of a dual-species optical tweezer for both Rb and K atoms, taking a step towards creating a polar-molecule optical tweezer array. Initially, Rb and K atoms are collected using a dual magneto-optical trap and further cooled to $7\phantom{\rule{0.28em}{0ex}}\textmu{}\mathrm{K}$ for Rb and $10\phantom{\rule{0.28em}{0ex}}\textmu{}\mathrm{K}$ for K. By employing 850-nm tweezer beams, we demonstrate the ability to capture individual Rb or K atoms. The filling ratios of Rb and K can be finely adjusted by controlling the atomic densities of both species. Utilizing the postselection technique, we can create a deterministic array of two-species atoms, paving the way for future polar-molecule array formation.