Toward Simultaneous Quantum Degeneracy of $^{133}$Cs and $^6$Li Atoms

A quantum degenerate mixture of $^{133}$Cs and $^6$Li atoms provides interesting prospects to investigate few- and many-body physics and to realize quantum information processing. Simultaneous evaporative cooling of bosonic $^{133}$Cs and fermionic $^6$Li is challenging. In an optical dipole trap formed with a 1064nm laser, $^{133}$Cs (resonant transition at 852nm) experiences a deeper potential than $^6$Li (at 671nm). Since laser cooling allows a much lower initial temperature for $^{133}$Cs (10$\mu$K) than for $^6$Li (150$\mu$K), a wide, shallow trap optimizes $^{133}$Cs loading, but $^6$Li requires a deep trap. Efficient cooling of $^6$Li involves Feshbach resonance tuning near 800G, but $^{133}$Cs collision properties are untested at high fields. Furthermore, sympathetic cooling of $^6$Li by $^{133}$Cs can suffer from the large mass ratio causing imperfect overlap of clouds and slow collisional rethermalization. We report our work toward collision studies of $^{133}$Cs -$^6$Li and $^{133}$Cs-$^{133}$Cs in fields up to 1000G and its implications for optimal evaporation, as well as the implementation of quantum gate operations.